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1 Standardization and optimization of index for 28 day strength for cement made from standard clinker By Anton Hermansson Supervisor: Tina Hjellström, Cementa Proposer: Patrick Thålin, Cementa Examiner: Associate Professor Matthäus Bäbler, KTH Summary This project regards the prediction of 28 day compressive strengths of cement. Using traditional multivariate analysis in combination with Artificial Neural Networks indexes have been developed which makes these predictions possible. Compressive strength is highly dependent on the cement hydration and clinker reactivity and literature on these topics have been studied followed by statistical analyses in Unscrambler X by Camo AS and the Neural Networks model created by Dr. Jan Skocek at Heidelberg Technology Center (HTC). The report and this project is initiated by a description of the cement production process as it is at Cementas Slite plant. Following this, the theory behind cement hydration and current state of research into this area is described along with description of the various tools that is used. After studying the theory behind compressive strength, some key parameters are identified including the Alite content, particle sizes as well as a variety of other parameters. Following this, a data set has been collected and formatted for the use in the project. Data on cement properties including compressive strength has been compiled by the quality engineer in Slite making the data collection simple. Having the data, the procedure includes a start with traditional multivariate analysis in Unscrambler to identify significant parameters in an effort of reducing the number of variables in the final model. In Unscrambler, Partial Least Squares regression has been used with uncertainty analysis as a selected option for parameter selection. Following the analysis in Unscrambler, the data set for each cement type is inserted into the neural networks models and the significant parameters are selected to act as input data, predicting either 1d or 28d strength. Before insertion into the Neural Networks model, the parameters are manually vetted with support of the literature and the accepted theories on cement hydration as correlations not necessarily mean that there is a causal link. Results are presented using the verification set of these indexes, indicating the prediction capacity of the indexes. Scenarios have also been used to study the underlying correlations between various properties and the compressive strengths. The results have shown good performance of the indexes created, and the procedure has proven to be fast and effective in creating these indexes. This opens up possibilities of using similar approaches to other areas of the plant in the future efforts to improve environmental and financial sustainability.

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Page 1: Standardization and optimization of index for 28 day ...kth.diva-portal.org/smash/get/diva2:1427516/FULLTEXT01.pdf · Table N1 - Cement chemistry notation Mineral Cement industry

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Standardization and optimization of index for 28 day strength for cement made from standard clinker By Anton Hermansson

Supervisor: Tina Hjellström, Cementa

Proposer: Patrick Thålin, Cementa

Examiner: Associate Professor Matthäus Bäbler, KTH

Summary This project regards the prediction of 28 day compressive strengths of cement. Using traditional

multivariate analysis in combination with Artificial Neural Networks indexes have been developed

which makes these predictions possible. Compressive strength is highly dependent on the cement

hydration and clinker reactivity and literature on these topics have been studied followed by statistical

analyses in Unscrambler X by Camo AS and the Neural Networks model created by Dr. Jan Skocek at

Heidelberg Technology Center (HTC).

The report and this project is initiated by a description of the cement production process as it is at

Cementas Slite plant. Following this, the theory behind cement hydration and current state of research

into this area is described along with description of the various tools that is used.

After studying the theory behind compressive strength, some key parameters are identified including

the Alite content, particle sizes as well as a variety of other parameters. Following this, a data set has

been collected and formatted for the use in the project. Data on cement properties including

compressive strength has been compiled by the quality engineer in Slite making the data collection

simple. Having the data, the procedure includes a start with traditional multivariate analysis in

Unscrambler to identify significant parameters in an effort of reducing the number of variables in the

final model. In Unscrambler, Partial Least Squares regression has been used with uncertainty analysis

as a selected option for parameter selection.

Following the analysis in Unscrambler, the data set for each cement type is inserted into the neural

networks models and the significant parameters are selected to act as input data, predicting either 1d or

28d strength. Before insertion into the Neural Networks model, the parameters are manually vetted

with support of the literature and the accepted theories on cement hydration as correlations not

necessarily mean that there is a causal link.

Results are presented using the verification set of these indexes, indicating the prediction capacity of

the indexes. Scenarios have also been used to study the underlying correlations between various

properties and the compressive strengths.

The results have shown good performance of the indexes created, and the procedure has proven to be

fast and effective in creating these indexes. This opens up possibilities of using similar approaches to

other areas of the plant in the future efforts to improve environmental and financial sustainability.

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Included in the final section of the report are also a few recommendations that would simplify the

future work on this topic.

Acknowledgements The author would like to thank the project group for invaluable support during this project and the

willingness at which experiences and knowledge has been shared. The project group includes Senior

Project leaders at Cementa Slite, Tina Hjellström (main supervisor) and Johan Larsson whose

experience and initiatives made the project work possible. A big thanks also to Quality manager

Patrick Thålin who is proposer of this project.

Large thanks are also directed at Investigation Engineer Alexander Åkerlund and Process Engineer

José Aguirre Castillo who have been invaluable resources during this work, sharing the knowledge on

the areas this project involves. Dr. Jan Skocek has also provided valuable input on the subject of the

Neural Networks model that he created.

Outside the project group the author also wishes to thank Quality Engineer Tore Jönsson whose

compilation of quality data over the year formed the basis for the data set used in this project.

Laboratory Group leader Karin Larsson’s work on compressive strength prediction as well as support

with the neural networks model has also been a valuable resource in this project.

A large thanks to Associate Professor Matthäus Bäbler who has been examiner for this project and

been the contact point between the project group and KTH.

Finally, a large thanks to Cementa who provided the opportunity and the resources for this project.

Nomenclature HTC – Heidelberg Technology Center

LSF – Lime Saturation Factor

SR – Silica Ratio

AR – Alumina Ratio

DoS – Degree of Sulfatization

IP21 – Process overview tool used at Cementa

LOI – Loss on ignition

TGA – Thermogravimetric Analysis

LIMS – Laboratory Information Management System

XRF – X-ray fluorescence spectroscopy

XRD – X-ray diffraction (crystallography)

CR – Cementa Research (main laboratory)

ANN – Artificial Neural Network

Cement chemistry notations

The cement industry uses shorthand for some of the most common compounds in cement chemistry.

Chemical

formula

Cement industry

denomination

CaO C

Al2O3 A

SiO2 S

Fe2O3 F

SO3 s̅

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Na2O N

K2O K

Ca(OH)2 CH

H2O H Table N1 - Cement chemistry notation

Mineral Cement industry

denomination

General chemical

formula

Alite C3S Ca3SiO5 3CaO∙SiO2

Belite C2S Ca2SiO4 2CaO∙SiO2

Aluminate C3A Ca3Al2O6 3CaO∙Al2O3

Ferrite C4AF Ca4Al2Fe2O10 4CaO∙Al2O3∙Fe2O3 Table N2 – Most common clinker minerals

Gypsum CaSO4·2H2O

Hemi-hydrate CaSO4·½H2O

Anhydrite CaSO4 Table N3 – Calcium sulfates

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Contents Summary ................................................................................................................................................. 1

Acknowledgements ................................................................................................................................. 2

Nomenclature .......................................................................................................................................... 2

Cement chemistry notations ..................................................................................................................... 2

Figures ...................................................................................................................................................... 8

1. Purpose ............................................................................................................................................. 10

1.1 Compressive strength index ........................................................................................................ 10

1.1.1 HTC Neural Networks model ................................................................................................ 10

1.1.2 Optimization of the model ..................................................................................................... 10

1.2 Sustainability ................................................................................................................................ 10

1.2.1 Ecological sustainability ........................................................................................................ 10

1.2.2 Financial sustainability .......................................................................................................... 11

2. Background........................................................................................................................................ 11

2.1 Cement production ....................................................................................................................... 12

2.1.1 Raw material ......................................................................................................................... 12

2.1.2 Preheating and Precalcining ................................................................................................. 13

2.1.3 Kiln stage ............................................................................................................................... 13

2.1.4 Clinker components............................................................................................................... 15

2.1.5 Finish grinding/Cement mills ................................................................................................. 15

2.1.6 Fly-ash addition ..................................................................................................................... 15

2.1.7 Shipping ................................................................................................................................ 16

2.2 Cement types ............................................................................................................................... 16

2.3 Concrete....................................................................................................................................... 16

2.4 Setting properties ......................................................................................................................... 16

2.5 Laboratories at Cementa in Slite ................................................................................................. 17

2.5.1 Samples tested ...................................................................................................................... 17

2.6 Analyzed parameters ................................................................................................................... 17

2.6.1 Particle size distribution (PSD) .............................................................................................. 18

2.6.2 X-ray fluorescence (XRF) ...................................................................................................... 18

2.6.3 X-ray diffraction (XRD) .......................................................................................................... 19

2.6.4 Compressive strengths & Setting time .................................................................................. 20

2.6.5 Other ..................................................................................................................................... 21

2.7 Sustainability ................................................................................................................................ 22

2.7.1 Life cycle view ....................................................................................................................... 22

2.7.2 Alternative raw materials ....................................................................................................... 22

2.7.3 Additives ................................................................................................................................ 23

2.7.4 Fly-ash ................................................................................................................................... 23

2.7.5 Alternative fuels ..................................................................................................................... 23

2.8 Previous work .............................................................................................................................. 23

3. Theory ................................................................................................................................................ 23

3.1 Alite, Belite & Aluminates ............................................................................................................. 24

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3.1.1 Alite (C3S) .............................................................................................................................. 25

3.1.2 Belite (C2S) ............................................................................................................................ 26

3.1.3 Aluminates (C3A & C4AF) ...................................................................................................... 26

3.2 Minor constituents ........................................................................................................................ 28

3.2.1 Set accelerators .................................................................................................................... 28

3.2.2 Sulfur ..................................................................................................................................... 29

3.2.3 Portlandite ............................................................................................................................. 29

3.2.4 Zinc ........................................................................................................................................ 29

3.3 Gypsum, Limestone & Fly-ash ..................................................................................................... 29

3.3.1 Gypsum ................................................................................................................................. 29

3.3.2 Limestone .............................................................................................................................. 30

3.3.3 Fly-ash ................................................................................................................................... 30

3.4 Hydration ...................................................................................................................................... 30

3.4.1 Calcium-Silicates reactions ................................................................................................... 30

3.4.2 Aluminate reactions ............................................................................................................... 31

3.4.2 Water/cement ratio ................................................................................................................ 32

3.4.3 Progression ........................................................................................................................... 33

3.4.4 Pozzolan reaction .................................................................................................................. 33

3.5 Strength development & Setting time .......................................................................................... 33

3.5.1 Setting time ........................................................................................................................... 34

3.5.2 1d strength ............................................................................................................................ 34

3.5.3 28d strength .......................................................................................................................... 34

3.6 Multivariate analysis ..................................................................................................................... 34

3.6.1 Multivariate analysis & regression ......................................................................................... 34

3.6.2 Excel regression tool ............................................................................................................. 35

3.6.3 Partial Least Squares ............................................................................................................ 35

3.7 Neural network ............................................................................................................................. 36

3.8 Bias-Variance ............................................................................................................................... 36

3.8.1 Sample stratification .............................................................................................................. 37

3.9 Sustainability ................................................................................................................................ 38

3.9.1 Reduced clinker content in the cement ................................................................................. 38

3.9.2 Reduced amount of virgin limestone ..................................................................................... 38

3.9.3 Process optimization ............................................................................................................. 38

3.9.4 Concrete carbonation ............................................................................................................ 39

4. Procedure .......................................................................................................................................... 39

4.1 Literature study ............................................................................................................................ 40

4.2 Data collection and preparation ................................................................................................... 40

4.3 Traditional Multivariate analysis ................................................................................................... 40

4.3.1 Excel ...................................................................................................................................... 41

4.4 Choosing parameters ................................................................................................................... 41

4.4.1 Initial exclusion ...................................................................................................................... 41

4.4.2 Uncertainty test ..................................................................................................................... 41

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4.4.3 Manual selection ................................................................................................................... 42

4.4.4 Unknowns .............................................................................................................................. 43

4.5 Selecting samples ........................................................................................................................ 43

4.5.1 Variations in laboratory equipment ........................................................................................ 43

4.5.1 Bias ....................................................................................................................................... 44

4.6 HTC model ................................................................................................................................... 45

4.6.1 Functions & Procedure .......................................................................................................... 45

4.6.2 Separate indexes for 1d and 28d .......................................................................................... 46

4.6.3 SH-cement ............................................................................................................................ 46

4.6.4 BAS-cement .......................................................................................................................... 46

4.6.5 Verification/validation ............................................................................................................ 46

4.6.6 Bias issue identification ......................................................................................................... 47

4.6.7 Bias-Variance balance .......................................................................................................... 47

4.6.8 Model parameters ................................................................................................................. 47

4.7 Clinker minerals ........................................................................................................................... 48

4.7.1 Analyzing clinker mineral impact ........................................................................................... 48

4.7.2 Procedure .............................................................................................................................. 49

4.8 Additional work ............................................................................................................................. 49

4.8.1 Macros ................................................................................................................................... 49

4.8.2 Anläggningsindex .................................................................................................................. 50

5. Results and Discussion ..................................................................................................................... 50

5.1 Verification ................................................................................................................................... 50

5.2 Procedure .................................................................................................................................... 51

5.2.1 Including 1d strength as parameter for 28d strength prediction ........................................... 51

5.2.2 Target of 2 MPa ..................................................................................................................... 51

5.2.3 Parameter selection .............................................................................................................. 51

5.2.4 Separate indexes .................................................................................................................. 52

5.2.5 Unscrambler models ............................................................................................................. 53

5.2.6 Anläggningsindex .................................................................................................................. 53

5.3 SH-cement ................................................................................................................................... 53

5.3.1 1 day index ............................................................................................................................ 54

5.3.2 28 d index .............................................................................................................................. 55

5.3.3 SH-Cement indexes discussion ............................................................................................ 57

5.4 BAS-Cement ................................................................................................................................ 57

5.4.1 1d........................................................................................................................................... 58

5.4.2 28 d ....................................................................................................................................... 59

5.4.3 BAS-Cement index discussion .............................................................................................. 61

5.5 Bias .............................................................................................................................................. 61

5.5.1 Model parameter variations ................................................................................................... 61

5.5.2 Sample selection ................................................................................................................... 63

5.6 Clinker minerals ........................................................................................................................... 64

5.6.1 Inconsistency ......................................................................................................................... 64

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5.6.2 Results .................................................................................................................................. 65

5.6.3 Combinations ........................................................................................................................ 65

5.6.4 Fly-ash ................................................................................................................................... 66

5.7 Difficulties ..................................................................................................................................... 67

5.7.1 Available data ........................................................................................................................ 67

5.7.2 Unknowns .............................................................................................................................. 67

5.7.3 Neural Networks model functionality ..................................................................................... 67

5.7.4 Early and late strengths ........................................................................................................ 68

5.8 Excel regression tool .................................................................................................................... 68

5.9 Sustainability ................................................................................................................................ 70

5.9.1 Fly-ash ................................................................................................................................... 70

5.9.2 PSD ....................................................................................................................................... 70

5.10 Tool development ...................................................................................................................... 71

5.10.1 Extraction tool for sample selection .................................................................................... 71

5.10.2 “IP21-fetch” .......................................................................................................................... 71

5.10.3 Tool development discussion .............................................................................................. 72

6. Conclusions/Recommendations ........................................................................................................ 72

6.1 Indexes......................................................................................................................................... 72

6.1.1 Sustainability ......................................................................................................................... 73

6.1.2 Setting time ........................................................................................................................... 73

6.1.3 Different strengths ................................................................................................................. 73

6.1.4 Non-linearity of index............................................................................................................. 73

6.2 Bias .............................................................................................................................................. 74

6.3 Recommendations ....................................................................................................................... 74

6.3.1 Additional particle sizes reported .......................................................................................... 74

6.3.2 Analysis result compiling ....................................................................................................... 74

6.3.3 Increased control of fly-ash ................................................................................................... 75

6.3.4 XRD, Clinker reactivity and Indexes ...................................................................................... 75

7. Further work....................................................................................................................................... 75

7.1 Indexes......................................................................................................................................... 75

7.1.1 Index maintenance ................................................................................................................ 75

7.1.2 Other uses of the model ........................................................................................................ 76

7.2 Sustainability ................................................................................................................................ 76

7.3 Process optimization .................................................................................................................... 76

References ............................................................................................................................................ 77

Appendices ............................................................................................................................................ 78

A1 - Partial Least Square Regression ............................................................................................... 78

A1.1 NIPALS algorithm .................................................................................................................. 78

A2 – Neural Networks ........................................................................................................................ 80

A2.1 Radial Basis Function Network .............................................................................................. 80

A3 – Unscrambler results for Bas and SH ......................................................................................... 81

A3.1 SH-cement ............................................................................................................................. 81

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A3.2 BAS-cement ........................................................................................................................... 84

A3.3 Anläggningscement ............................................................................................................... 87

A4 – Clinker mineral correlations ....................................................................................................... 88

A4.1 Scenarios 28d SH .................................................................................................................. 88

A4.2 Scenarios 1d .......................................................................................................................... 93

A4.3 Flyash ........................................................................................................................................ 97

A4.3.1 Fly-ash content on 28d ....................................................................................................... 98

A4.3.2 Fly-ash on 1d strength ...................................................................................................... 100

A5 – Sample selection VBA ............................................................................................................. 101

A6 – IP21 fetch ................................................................................................................................ 106

Figures Figure 1 - Cement production process overview ................................................................................... 12 Figure 2 - Typical reaction process in a cement kiln from Heidelberg Cement World-of-Knowledge ... 14 Figure 3 - Factors contributing to clinker reactivity [12] ......................................................................... 24 Figure 4 - Phase diagram of CaO-SiO2 system during clinker burning [13] .......................................... 25 Figure 5 - Ettringite and calcium hydroxide [4] ...................................................................................... 27 Figure 6 - Impact and limits of Na2O and Fe2O3 on polymorphism [13] ................................................ 27 Figure 7 - 1: Hydration of C3S after 5 min. 2: Formation of needle shapes of CSH after 16 h. 3: Needles up to 900 nm in size 21 days [4] ............................................................................................. 31 Figure 8 - Water/Cement ratio [4] .......................................................................................................... 32 Figure 9 - Cement hydration progression [14] ....................................................................................... 33 Figure 10 - RBFN Neural Network explanation [18] .............................................................................. 36 Figure 11 - Bias vs. Variance [19] ......................................................................................................... 37 Figure 12 - Distribution of samples 28 day strength BAS-cement from Unscrambler ........................... 37 Figure 13 - Uncertainty analysis results from Unscrambler .................................................................. 41 Figure 14 - Na2O measured on the same samples (only SH-cement), sorted chronologically ............. 43 Figure 15 - Histogram for 1d strengths BAS-cement ............................................................................ 44 Figure 16 - Histogram for selected 1d samples for BAS-cement .......................................................... 45 Figure 17 - GUI for model parameter adjustment in the ANN model .................................................... 48 Figure 18 - The GUI for creating scenarios in the ANN model .............................................................. 49 Figure 19 - Verification sets for 2 model runs from ANN model ............................................................ 50 Figure 20 - Difference between Carbon-Sulfur determinator and XRF for SO3 .................................... 52 Figure 21 - Results of analysis on SO3 on XRF and Carbon-Sulfur determinator ................................ 52 Figure 22 - The difference between measured and predicted for 1d strength SH-cement from HTCs model ..................................................................................................................................................... 55 Figure 23 - The difference between measured and predicted for 28d strength (without 1d as input) SH-cement from HTCs model ...................................................................................................................... 56 Figure 24 - The difference between measured and predicted for 1d strength BAS-cement from HTCs model ..................................................................................................................................................... 59 Figure 25 - The difference between measured and predicted for 28d strength BAS-cement from HTCs model ..................................................................................................................................................... 60 Figure 26 - Histogram for 28d strength for SH-cement from Unscrambler ........................................... 63 Figure 27 - Error plotted against measured strength for selected samples 28d BAS ........................... 64 Figure 28 - Alite_sum plotted against Belite_beta in Unscrambler ....................................................... 66 Figure 29 - Error vs measured strength from Excel .............................................................................. 69 Figure 30 - X- and Y-loadings for 1d model for SH-cement .................................................................. 79 Figure 31 – The number of components impact on the degree of explained Y-variance ..................... 79 Figure 32 - Weighted coefficients for significant variables from Unscrambler for 1d SH ...................... 82 Figure 33 - PLS model performance for 28d for SH-cement from Unscrambler ................................... 83 Figure 34 - Weighted coefficients for SH 28d strength from Unscrambler (blue marked as insignificant) ............................................................................................................................................................... 83 Figure 35 - PLS model performance for 28d for SH-cement from Unscrambler ................................... 84 Figure 36 - Weighted coefficients for significant variables from Unscrambler for 1d BAS .................... 85

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Figure 37 - PLS model performance for 1d strength BAS from Unscrambler ....................................... 86 Figure 38 - Weighted coefficients for significant variables from Unscrambler for 28d BAS .................. 86 Figure 39 - PLS model performance for 1d strength BAS from Unscrambler ....................................... 87 Figure 40 - PLS model performance from Unscrambler for Anläggningscement ................................. 87 Figure 41 - Weighted coefficient (only significant) from Unscrambler ................................................... 88 Figure 42 - 28d strength as variation in Alite content ............................................................................ 89 Figure 43 - 28d strength as variation in fraction of M1 Alite to Alite sum .............................................. 89 Figure 44 - 28d strength depending on Belite content .......................................................................... 90 Figure 45 - 28d strength depending on variation in Aluminate content ................................................. 90 Figure 46 - 28d strength depending on cubic C3A ................................................................................ 91 Figure 47 - 28d strength depending on variations in orthorhombic C3A content .................................. 91 Figure 46 - 28d strength depending on variations in Aphthitalite content ............................................. 92 Figure 47 - 28d strength depending on variations in Arcanite content .................................................. 92 Figure 50 - 28d strength depending on variations in Langbeinite content ............................................ 93 Figure 51 - 1d strength depending on Alite content .............................................................................. 93 Figure 52 - 1d strength depending on fraction of M1 to total Alite content ........................................... 94 Figure 53 - 1d strength depending on Belite content ............................................................................ 94 Figure 54 - 1d strength depending on total Aluminate content ............................................................. 95 Figure 55 - 1d strength depending on cubic C3A content ..................................................................... 95 Figure 56 - 1d strength depending on orthorhombic C3A content ........................................................ 96 Figure 57 - 1d strength depending on the Aphthitalite content ............................................................. 96 Figure 58 - 1d strength depending on the Arcanite content .................................................................. 97 Figure 59 - 1d strength depending on the Langbeinite content ............................................................. 97 Figure 60 - 28d strength variations depending on fly-ash content ........................................................ 98 Figure 61 - 28d strength variations depending on fly-ash content ........................................................ 99 Figure 62 - 28d strength variations depending on fly-ash content ...................................................... 100 Figure 63 - Fly-ash impact on 1d strength from HTC model ............................................................... 100

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1. Purpose The objectives in this project is both optimizing and standardizing a tool which can be used for

prediction of compressive strengths in cement and also increased understanding of parameter

relationships in the cement. The main focus on understanding the parameter relationships is the

increased knowledge on the impacts of clinker minerals on the compressive strengths of cement.

1.1 Compressive strength index Having an index for prediction of compressive strengths of cement produced will benefit both

Cementa and the customer. Identifying issues with compressive strengths at an early stage will allow

for customers to adapt recipes to avoid failures. It can also possibly help Cementa identify issues

within the production process. This will strengthen the customer confidence in the product as well as

reducing the risks for impacts on Cementa.

1.1.1 HTC Neural Networks model HTCs neural networks model is already used to predict the 28-day compressive strength of one cement

type: Anläggningscement. However, indexes are specific for each cement type as the chemical

composition and physical properties varies between the different types.

A good target for the model is that it should predict the strength within ±2 MPa of the measured value.

However, with this target in mind it should be noted that the 95% confidence level (2 x total

measurement uncertainty) is 9% for 1d strength and 5% for 28d strength. For the cement types studied

in this project, this represents roughly 2 MPa for 1d strength and 3 MPa for 28d strength.

1.1.2 Optimization of the model The optimization in this project is finding a good balance between usability and precision. A model

using only the results from the process laboratory will have high usability as the results are quickly

gained, however the precision will be lower as the analyses there have lower accuracy.

A good model have to be precise and be based on independent and a limited number of variables. At

the process laboratory, samples are run quickly and both XRF, XRD and particle size distribution are

analyzed at that laboratory. To be able to quickly calculate and estimate the strength of the cement,

using only these results would be optimal.

1.2 Sustainability In the development of products as well as optimization of the process, knowledge on the clinker

impact is vital. Using an increased understanding of the clinker minerals impact on the compressive

strength of the cement can allow for a more sustainable production.

1.2.1 Ecological sustainability Clinker burning requires high temperature and large amounts of CO2 is emitted from this step in the

production process, not only from the fuel, but also from the calcination of the limestone. Several

ways to reduce the impact of this stage on the environmental performance of the finished product is

already being used. This includes optimizing the burning process, reducing the clinker content in the

cement and reducing the amount of limestone burned.

Replacing raw materials or lowering the clinker content of the cement has to be balanced against the

quality of the cement. Understanding of the clinker mineral impact on the compressive strengths can

for that reason benefit the further measures taken in this area.

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1.2.2 Financial sustainability While ecological and financial sustainability is connected to an increasing extent, the increased

understanding of the clinker mineral impacts (in combination with tools similar to the ones used in this

project) can lower production costs for the cement.

The costs and quality of raw materials fluctuate and using knowledge on clinker minerals can help

determine and adapt recipes to account for these fluctuations without risking compressive strength

issues. While the chemical composition as well as content of various alternative raw materials are

regulated by standards as well as agreements with customers, small changes in the amount of, for

example fly-ash, mixed into the cement can be made without violating these. This can therefore be

optimized to some extent to account for fluctuations.

2. Background The quality of the cement is crucial for the consumer of the cement. In case of deviations in quality the

consumers may need to adapt recipes, or they may experience failures which are costly to correct. To

ensure the quality of the cement, Cementa runs multiple analyses on the cement shipments and during

the production process.

Certain analyses takes longer to run than other though, an example of this is the 28 day compressive

strength. This analysis requires 28 days of strength development to take place, meaning that the results

for a specific sample is available no sooner than 28 days from the shipping date. A credible

model/index that can quickly predict the 28 d strength will benefit both Cementa and the consumer;

the consumer will be able to adapt their recipe to account for unsatisfactory quality and Cementa can

find and correct issues with the strength at an early stage.

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2.1 Cement production

Figure 1 - Cement production process overview

As can be seen in Figure 1, the cement production process involves multiple steps and different types

of processes. The production of cement is a highly automated process and is monitored and controlled

from a control room at the plant. The process is monitored through both sensors located at various

points in the process, scales and through analyses in the production laboratory where samples are

analyzed at set times throughout the day.

2.1.1 Raw material The main raw material for cement production is limestone. At Cementa in Slite two qualities of

limestone are used: Limestone and marl. Marl has a higher clay content and a lower content of calcite

compared to pure limestone. The raw material is mined in quarries located close to the plant by

blasting the quarry walls. Quality of the stone varies depending on the location of the blasting and later

mixing of the resulting rocks are planned by geologists to ensure a consistent quality.

The blasted rocks are mixed according to a recipe and crushed down to a diameter below 80 mm and

homogenized during storage in a large storage facility. Additional materials are also added at this point

to further enhance the properties.

From the storage facility, the rocks are transported on conveyors to the raw mills. At Cementa’s Slite

plant, there are 2 raw mills, each serving a separate kiln line. However, the transport from the quarry is

shared between the two kiln lines. At the raw mills, other additives are added mainly sand and iron

oxide. These materials are not mined at the plant but bought/imported from other suppliers.

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Sand is hard and requires a large amount energy to grind, and at Cementa Slite it is pre-ground in

separate mills and mixed with where water is added to reduce dust containing fine quartz-particles

form a slurry.

The raw mills are vertical roller mills and depend on the hot kiln gases to dry and carry the finer

material to a separator located above the mill. For that reason the raw mills cannot run without the

kilns. The resulting product from the raw mills is called raw meal and is stored in silos before moving

to the next stage.

2.1.2 Preheating and Precalcining The formation of clinker, the main constituent of cement, requires heating of the raw meal to high

temperatures. To increase the thermal efficiency of the production process the raw meal is preheated

using the hot gases from the kiln, this is done in large towers with several stages of heat exchangers in

the form of “cyclones”.

As previously mentioned, Cementas Slite plant has two kiln lines, where kiln line 7 is older and

smaller and kiln line 8 is the more modern and larger one. In the more modern kiln line, the material,

in addition to being preheated, is also precalcined. This is done in a calciner close to the kiln inlet.

The calciner further increases the energy efficiency of the process by calcining part of the material

before it enters the kiln. This is aided by the flow of tertiary air from the cooler. The calcination

reaction is the removal of carbon dioxide (CO2) from calcium carbonate (CaCO3) and is vital for the

formation of clinker.

CaCO3 → CaO + CO2

Formula 1 - Calcination reaction

The calcination reaction accounts for a large portion of the carbon dioxide released by the plant.

2.1.3 Kiln stage The kiln stage including the calcining is by far the most energy demanding step in the process as the

calcining step is endothermic and although the formation of clinker mineral is exothermic, it requires

the material to be heated to roughly 1450°C. The fuel used at the Slite plant is a mixture of fossil fuels

and “alternative” fuels. The alternative fuels are a mixture of waste plastics, biofuels and waste oils.

The share of the alternative fuels varies, but at the Slite plant the majority of the fuels used are

alternative fuels.

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Figure 2 - Typical reaction process in a cement kiln from Heidelberg Cement World-of-Knowledge

The temperature in kiln varies along the length of the kiln. Figure 2 shows the areas where formation

of the various minerals typically takes place. However, as previously mentioned, kiln 8 have a calciner

before the kiln meaning that the picture best resembles and represents kiln 7.

From the preheating to the cooler, the air streams are specified by the location of introduction into the

system. The primary and secondary air is introduced in the burner and the kiln stage. The tertiary air is

air originating at the cooler, and the heat energy of this air flow contributes to the calcining.

The burner is located at the end of the kiln, giving the highest temperature area (sinter zone) close to

the outlet of the kiln. The short section after the burner is the precooling zone which starts the cooling

process.

After the kiln, the clinker falls into a cooler to rapidly cool the material. This is necessary as the

clinker mineral Alite, the main constituent providing strength during the first 28d, is

thermodynamically unstable. Rapid cooling “freezes” these minerals in their configuration.

The reactions and formation temperatures of the main contributors to the strength of the cement are

[1]:

Belite: 2 CaO + SiO2 → Ca2SiO4 at 800 − 1,250℃

Alite: CaO + Ca2SiO4 → Ca3SiO5 at 1,350 − 1,450℃

Formula 2 - Formation of Alite and Belite in the kiln [1]

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After the cooler, the clinker is transported to silos for storage.

2.1.4 Clinker components Cement consists mainly of clinker which in turn consists mainly of different minerals [1]. The

minerals contribute to the properties of the cement in different ways. The main minerals that make up

clinker along with typical concentrations are shown in Table 1.

Name Formula Concentration (%)

Alite C3S 50-70

Belite C2S 5-25

Aluminate C3A 2-10

Ferrite C4AF 5-12

Free lime CaO 0.5-2

Periclase MgO 0-3

Alkali sulfates 0.8-2.5 Table 1 - Typical mineral content of clinker [1]

The different components provide the clinker with different properties. C3S and C2S are responsible

for the majority of the strength development of the cement, C3S reacts quickly with water and is

responsible for the majority of the strength development for the first 28d. C2S reacts slower and

contributes to the strength development mainly from 28d to up to 5 years. [1]

In industrially produced clinker, the phases also contain other components embedded in the lattice,

these stabilize different crystal configurations.

2.1.5 Finish grinding/Cement mills The last stage is the grinding of the clinker along with additives to form the cement. The amount of

clinker to other materials varies depending on the type of cement being produced and the expected

properties of the product. At this stage, gypsum is added along with limestone. The mills at Cementa

are ball mills, meaning that they use steel balls which crushes and grinds the material.

The general chemical composition of gypsum is CaSO4 in complex with H2O, and the sulfates are

important to regulate not only the setting time of the cement but it also contributes to the strength. In

the case of BAS-cement, gypsum slurry from the desulfurization scrubber in Slite is also added during

grinding. As this slurry contains both gypsum and water this functions both as a gypsum source as

well as cooling. [1]

The finished particle size of the cement after the mills depends on the type of cement being produced.

The particle size is controlled by a separator, where the coarser material is returned to the mill. For a

cement with smaller particle sizes the particles are recirculated more times, giving the particle longer

total time in the mills.

Other additives at this point are a ferrous sulfate (FeSO4) which acts as a reduction agent for

chromium. Chromium in the raw material is oxidized at the high temperatures in the kiln to form Cr6+

which is hazardous to human health. To reduce this back to an oxidation level where Chromium is less

dangerous at Cementa FeSO4·7H2O is added to the cement.

2.1.6 Fly-ash addition After the cement mills Cementa adds fly-ash to their main products. The fly-ash cements accounts for

roughly 45% of the sales of cement from Slite. Fly-ash is a waste material from coal combustion, it is

a pozzolan material and contains mainly silicon (Si) and alumina (Al). A puzzolan material like fly-

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ash has the capability of reacting with calcium hydroxide Ca(OH)2 in the presence of water to behave

similarly to cement. [2]

Adding fly-ash reduces the clinker fraction of the cement improving the environmental performance of

the product.

2.1.7 Shipping All cement produced in Slite is shipped in bulk transport, most of it by ship but also a small portion by

truck. When a ship is loaded, a sample, in compliance with the demands of the standard, is taken from

the transport conveyor to the ship. The majority of the cement shipped from Slite is destined for

terminals around Sweden, however cement is also exported to various some countries.

2.2 Cement types In Europe, the standard EN197-1 is used to classify cement. The classification is done based on the

contents, the strength and the strength development. [3]

SH-cement is classified as CEM I 52.5 R. CEM I means that it contains 95-100% clinker, 52.5 is the

minimum strength after 28-days and the R indicates that it has a rapid strength development and that

the strength after 2 days should be above 30 MPa for this case.

BAS-cement is classified as CEM II/A-V 52.5 N. CEM II/A-V means that it can contain 6-20% silica-

aluminum containing fly-ash, N means that it has a normal strength development speed and in the

standard this is defined by a 2-day strength above 20 MPa. [3]

2.3 Concrete Concrete is the mixture of cement, sand, aggregates and water. As the most important component,

cement is the “glue” binding the mixture together. It is one of the most widely used construction

materials and has a wide variety of applications and benefits.

The hardening or setting of the concrete is determined by the properties of the cement which impact

the “hydration”. The hydration is a term used to describe the reactions that take place once the cement

is mixed with water. Cement forms C-S-H which binds together the aggregates by formation of

needle-like structures growing into each other.

Concrete structures often contain reinforcing steel bars as the concrete, while having good

compression strength, lacks tensile strength. These steel bars also limits the chemical composition of

the cement to minimize corrosion.

2.4 Setting properties Certain properties are expected from the customer on the cement as it sets. Firstly, the cement should

set within a certain timeframe. Too fast setting and hardening means that the cement is difficult to

work with for the customer, it cannot be below 60 min. A slow setting time (above 200 min) is

typically also viewed as negative by the customer as this leads to longer production times for the

customer, it also increases the risk of separation. [1]

As mentioned above, the strength development is also regulated depending on the cement type.

Other properties of the setting which need to be controlled is the heat development as the cement sets,

which is limited as heat development during the first 7 days of setting. This depends on the clinker

mineral content. [1] [4]

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2.5 Laboratories at Cementa in Slite There are two laboratories at Cementa’s Slite plant, one located by the control room (process

laboratory) and a larger laboratory (Cementa Research) in a separate building. These have different

purposes and are for that reason set up differently to fit these.

The process laboratory is highly automated and typically analyzes samples from the process. Several

samples from the process are conducted every day at set times, and as the results aims at providing

guidance with regards to process control, quick results are necessary. Cement leaving the plant by ship

is also analyzed at the process lab on XRF, XRD and PSD as described below. These results form a

major part of the data set in this project.

Cementa Research (CR) is an accredited laboratory, meaning that the laboratory is approved by a

government agency and follows the regulations for quality control. The analyses at CR are typically

more complex or time consuming but has a higher accuracy than the process laboratory analyses.

2.5.1 Samples tested There are several types of samples tested on several different materials at the different laboratories.

2.5.1.1 Process samples

The bulk of the samples analyzed at the process laboratory are process samples. These are scheduled at

intervals and include various intermediate products from the different kiln lines as well as the finished

product from the mills. Process samples reflect the state of the process and aids the operators as well

as production engineers in optimizing the process as well as identifying issues. For cement, the

analyses run at the process laboratory is XRD, XRF and PSD.

Process samples are to a lesser extent tested at CR as the analyses takes longer meaning that the

process condition may have changed before a result is available.

2.5.1.2 Dispatch samples

Samples of the shipments of cement and in certain cases intermediary products are conducted at both

the process laboratory and CR. At the process laboratory the same analyses are conducted on the

dispatch samples as on the process samples.

At CR additional analyses are conducted on the products, including compressive strength, setting time

as well as various chemical and other physical testings. The analyses conducted as well as the limits

are regulated according to the standard EN197-1.

2.5.1.3 Additional samples

To identify issues, optimize the process and as parts pf projects, samples are collected from various

points in the process. The analyses run on these samples varies depending on the purpose for

collecting the sample and the types and amounts of samples also vary.

Notable cases for additional samples being collected are crash-stops of the mills, where several

samples are collected from the mills to check the performance of the mills. This is to conduct process

or product optimization, achieving the optimal quality and analyzing the performance of the mills.

2.6 Analyzed parameters The analyses run on the shipment samples provides the data set for this project.

Analyses are conducted on samples from steps in the production process including the raw materials,

“intermediate products” (like clinker), fuels and the finished product. These analyses are both quality

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control as well as a means to control and optimize the process. Several of the analyses run are

specified and described in the standards regulating cement testing EN196-1 through EN196-9.

The analyses run at Cementa are also described in internal documents “methods” that describe the

procedures and use of the equipment at the laboratories. The majority of the methods run at CR are

accredited, meaning that the procedure, equipment, controls etc. are audited by a national agency to

ensure that these are in compliance with the regulations and standards regarding these.

2.6.1 Particle size distribution (PSD) The sizes of the particles in the cement impact the cement properties, as the particles become smaller,

the specific surface area increases. This increases the rate of the reaction. However, to achieve a finer

cement more energy has to be used in the grinding stage. [1]

Particle size distribution is analyzed at Cementa using laser diffraction, typically the result is reported

as a cumulative size distribution, giving the relative number of particles below a certain size.

However, d50 is also provided, which is the size where 50% of the particles are below this size, the

value is in µm. In the data set used in this project, 32 µm, 32-2 µm (the percentage of particles

between 32 µm and 2 µm) and d50 is given from the process laboratories PSD analysis. 32-2 µm

represents the most active particle size in terms of cement strength development and clinker reactivity.

2.6.1.1 Blaine Specific surface area

A common measurement on the specific surface area of the cement is the Blaine method of air

permeability through a known volume of sample. The surface area is highly dependent on the PSD of

the cement and the methods used for measurement of PSD are robust and provides a lot of information

on the cement. However, the Blaine method is still used for certain cement types.

Regarding BAS-cement, where the fly-ash addition results in it being essentially a mixture of two

components of different surface area and where the particles have different shapes and properties,

Blaine is not currently used.

For SH-cement where the setting time and early strength development is key, Blaine is analyzed at

CR.

2.6.2 X-ray fluorescence (XRF) The XRF analysis provides the content of the most important elements in the cement namely:

SiO2

Al2O3

Fe2O3

CaO

MgO

SO3

K2O

Na2O

Cl

ZnO

Quantitative analysis of these elements are mainly done at the process laboratory, however, certain

samples are run at CR as well. The analysis is conducted in different states at the main laboratory

compared to at the process laboratory.

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CR runs the analysis on glass disks prepared by melting the sample with a lithium borate substance.

Before the sample is melted the sample is heated to high temperature allowing for loss-on-ignition

analysis to be conducted if requested, this involves heating the sample to 950°C until constant weight.

As the sample is melted at high temperature, any weight loss at this stage would interfere with the

sample concentration and test results. A consequence of the heating is also that SO3 cannot be

analyzed accurately as some of the sulfur will be released into the exhaust during the melting phase.

However, the fused disks provide a homogenous sample and good accuracy on the analysis. Fusing

temperature must be kept stable as a variation in this may lead to various amounts of loss of sulfur

from the sample.

At the process laboratory, XRF is done on pressed powder disks without heating the sample before.

While being quicker and allowing for measuring of SO3, the sample is less homogenous and the

precision of the analysis may be lower.

The importance of the chemical content will be discussed in the following parts of this report.

2.6.3 X-ray diffraction (XRD) The XRD analysis provides information on the mineralogical content of the product. The main

minerals and compounds reported are:

Alite Crystal size

Alite M1

Alite M3

Alite sum

Cubic Aluminate (C3A)

Orthorhombic Aluminate (C3A)

Aluminate sum

Anhydrite

Aphthitalite

Arcanite

β-Belite

Calcite

CO2 (calculated)

Free lime

Fly-ash sum

Fraction M1

Dihydrate gypsum

Hemi-hydrate gypsum

Langbeinite

Lime

Periclase

Portlandite

Quartz

SO3 (calculated)

The minerals will be further discussed in chapter 3. Theory.

In addition to these parameters which are reported in the document, the Ferrite (C4AF) content is also

analyzed along with the content of the minerals Dolomite, Hematite, Magnetite and Mullite.

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2.6.3.1 Rietveld

The XRD analysis result in a spectrogram with peaks of varying height, width and location along the

x-axis (measuring 2θ angels). The minerals have known patterns of peaks at various 2θ-angels, and

using this allows for quantification of the minerals. The Rietveld method for analyzing the XRD data

allows for fast and automated quantification of the various minerals. The method works by fitting a

theoretical spectrogram to a measured spectrogram using a least squares approach. [5]

While XRD/Rietveld measures several important parameters impacting the cement properties, it also

has drawbacks. XRD only measures the crystalline components of the sample and the Rietveld method

normalizes the results to 100 wt%, meaning that the assumption that only crystalline compounds are

present in the sample or that the amorphous components impacts the spectrogram.

The XRD/Rietveld method is also sensitive to the fineness of the material being analyzed. In the

method used at the process laboratory the sample is prepared and ground, however, for the fine SH-

cement overgrinding can easily happen reducing measurement precision.

Residual from the Rietveld determination is indicated by the R_wp parameter, a higher R_wp value

means a worse fit for the curve.

2.6.4 Compressive strengths & Setting time The compressive strengths and setting times are key features for the produced cement, these properties

are characterized by the following quantities:

1 day compressive strength

2 day compressive strength

7 day (for SH only) compressive strength

28 day compressive strength

Setting time (Vicat_EN)

H2O

Soundness

Knowing that the cement will be strong enough to carry other components during construction or

maintain its shape when casting in forms is important to the consumer.

2.6.4.1 Setting time

The setting time is measured by mixing with water to a set consistency. The water demand is

measured and the sample is placed in a machine which drops a needle into the sample at set intervals.

When the needle no longer penetrates the paste, the sample has set.

The H2O demand to reach the required consistency also varies depending on the chemical and physical

properties of the cement.

2.6.4.2 Compressive strengths

The compressive strength testing at CR is done on mortar, a mixture of cement, sand and water. This

is cast in molds to form “prisms”, compacted and allowed to set for the amount of time specified by

the analysis. A standardized type of sand is used and every step of the procedure is specified in the

method, including the mixing times and compacting settings. The number of prisms cast varies

depending on the number of ages at which compressive strengths shall be tested, 3 prisms are cast for

each age.

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During the first day of the setting the prisms are stored in a cabinet with 90% relative humidity and at

a temperature of 20°C. After the first day, the 1d strength analysis is done on three of the prisms cast,

the rest of the prisms are allowed to age in a water bath. Before testing, the prisms are split and a total

of 6 tests are conducted on 3 prisms from each age.

2.6.4.3 Soundness

Soundness is also tested at CR in regards to the expansion of the cement during setting. Uncontrolled

expansion may cause adverse effects for the customers and needs to be kept within reasonable limits.

2.6.5 Other Other quantities used to characterize the produced cement at Cementa are:

SO3 – Carbon-Sulfur determinator

Limestone – Calculation based on CO2 content, not on BAS-cement.

Insoluble residue

Loss on ignition (LOI) – Thermogravimetric Analysis

Limestone content – Weight loss method for BAS-cement

Free Lime (wet chemical method)

Chloride content

Cr6+ reduction capability

Gypsum hydration through (STA-TG)

2.6.5.1 Carbon-sulfur determination

While sulfur is analyzed in the XRF in the process laboratory, a more accurate result is obtained from

the carbon-sulfur determinator at CR. Heating the sample through induction, the resulting gases are

analyzed by infrared detectors and the portion of both carbon and sulfur in the sample is determined.

As the high temperature will calcinate the limestone to produce CO2, the limestone content can for

most cement types be calculated to some degree of certainty using the results of this analysis. As BAS-

cement contains fly-ash which may contain other sources for carbon, this is not done on BAS-cement.

2.6.5.2 Insoluble residue

The insoluble residue of the cement is analyzed by subjecting the cement to acids and bases. It is one

of the regulated parameters of the cement, and must not exceed given levels for certain cement types.

2.6.5.3 Loss on ignition (LOI)

Loss on ignition is measured through a thermogravimetric analysis (TGA), which heats the sample to

950°C and weighing the sample at intervals until constant weight. While being an important stage in

the preparation for measurement on the XRF at CR, the LOI is also a parameter providing some

information on the cement.

2.6.5.4 Free lime

The content of free lime is measured through a titration analysis at CR. Free lime is important to

control as high levels can cause cracks in the cement as it sets. It is also analyzed through the XRD,

although the titration method is more accurate.

2.6.5.5 Chloride content

While chloride content can be measured through the XRF, the water soluble chloride content is also

important to control. This is measured through ion-chromatography at CR after first mixing the

cement with water, boiling the liquid and filtering out the solids. Chloride can have many effects in the

finished product and the level is limited to 0.1% in the cement because of corrosion. [6]

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2.6.5.6 Cr6+ reduction capability

Cr6+ is hazardous to human health and can cause allergic inflammation, skin irritation etc. Chromium

is present in the refractory in the kiln, steel balls in the mills and steel plates in the clinker cooler and

is transferred into the material during the manufacturing process. Chromium introduced before or

during the clinker burning may oxidize to Cr6+. Addition of iron sulfate reduces the chromium to Cr3+,

a less harmful state. The reduction capability is regulated and when encountering samples with low

reduction capability the total amount of soluble Cr6+ is measured in addition to the reduction capability

at CR. [2] [6]

2.6.5.7 Gypsum dehydration

The gypsum content and the water content of the gypsum is measured at CR through thermal analysis

(STA) where the weight loss is measured through thermogravimetric analysis simultaneously as DSC

(differential scanning calorimetry) measures the heat demand for a temperature increase. Syngenite

and Portlandite content is also measured through this method for certain samples. [7]

The different hydrates vary in solubility during the hydration depending on temperature, hemi-hydrate

dissolves quicker than gypsum (di-hydrate).The SO42- in the solution will facilitate the formation of

ettringite AFt which in turn slows down the reactions of alite and the aluminates to improve the

handling properties of the paste. [8] [6]

2.7 Sustainability Concrete accounts for roughly 95% of the construction materials used worldwide and the cement

manufacturing accounts for roughly 5% of the total global CO2 emissions. Among Swedish industries,

Cementas plant in Slite was the second largest emitter of CO2 in 2016. [9] [10]

Cementa has an ambitious project of achieving climate neutral cement by 2030. Both the fuels used

and the calcination reaction are sources of CO2 emissions and today roughly 40% of Cementa’s

emissions are from fuels, the other 60% is from the raw material: Limestone. Cementa will use a

combination of actions and developments to counter these emissions: Increased energy efficiency,

biofuels, new cement types with additional materials, Carbon Capture and Storage (CCS) and

carbonation (absorption of CO2 into the finished concrete structure).

Environmental and financial sustainability are also highly connected. Innovative products and

production techniques can lower both costs and emissions, especially when the cost of CO2 emissions

increase. Consumers may also demand or desire more sustainable products in the future.

Cementa currently works to improve sustainability in several areas, including alternative materials

added to the production process and using alternative fuels.

2.7.1 Life cycle view The sustainability work at Cementa and the target of climate neutral cement in 2030 is centered around

the entire life cycle of the product.

2.7.2 Alternative raw materials Using alternative materials in the process can benefit the sustainability of the final product. The

materials can be added at different points in the process depending on the properties of the material

and the need for processing.

Today, mixing slag into the raw materials are tested at the plant. Reducing the amount of virgin

limestone and decreasing the calcination need, and by extension lowering the CO2 emissions from the

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process. A reduction in the amount of virgin limestone can also lower the impact from the mining step

in the process.

2.7.3 Additives Waste materials from the cement production process itself are also used as filler in the final product.

The product called Cement Kiln Dust (CKD) are added to the cement, the amount possible to add

being regulated by the type of cement and the chemical composition.

CKD is high in chlorides and originates from the clinker burning stage. A cement type called

Multicem which is produced by Cementa for ground stabilization contains a high share of CKD,

however CKD is added to other products to a lesser degree as well.

2.7.4 Fly-ash Fly-ash is used in BAS-cement to reduce the share of clinker in the final product. It is a pozzolan

material, meaning that it contributes to the strength of the cement to some degree and acts as a reactive

additive rather than simply a filler.

2.7.5 Alternative fuels Cementa also focuses on reducing the amount of fossil fuels in the clinker burning process, and today

a majority of the fuels used are classified as “alternative fuels”. Roughly half of the alternative fuels

used are bio-based (including paper, wood and fabric) and the other half is fossil based (plastics, tires

and waste oils and solvents). Using waste as alternative fuels allows for extraction of the chemical

energy and prevents the waste from ending up in landfills.

2.8 Previous work Engineers at Cementa have worked on 28d compressive strength predictions in the past, however

mainly using traditional multivariate analysis in Excel. [11]

With the development of the Neural Networks model by Dr. Jan Skocek at Heidelberg Technology

Center a robust tool for modelling various parameters in cement production is available. The Artificial

Neural Networks (ANN) model provides a good and user-friendly way of making predictions on not

only cement performance but can be applied to other areas of the process as well.

3. Theory The compressive strength of the cement depends on several parameters. The strength is mainly formed

through the hydration of Alite and Belite to form C-S-H. It forms needle-like structures which grows

into each other. However, several other parameters impacts this reaction, both positively and

negatively.

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3.1 Alite, Belite & Aluminates

Figure 3 - Factors contributing to clinker reactivity [12]

The strength development of the cement is highly dependent on the clinker reactivity, defined by Dr.

Marsicano as “The contribution of all clinker phases, when hydrated, towards the strength

development is defined as clinker reactivity.” Figure 3 indicates the number different factors that

contribute to clinker reactivity. [12]

Alite, Belite, Aluminate and Ferrite, the main minerals components of clinker, are formed in the kiln.

Figure 2 provides a simplistic perspective on the regions, temperatures and concentration of these

minerals in a typical cement process, however these are not the only minerals which can form. The

phase diagram in Figure 4 illustrates the large number of minerals that can be formed from CaO-SiO2

during the clinker burning depending on concentrations and temperature.

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Figure 4 - Phase diagram of CaO-SiO2 system during clinker burning [13]

Depending on temperature and content of the chemical compounds which form the minerals, a large

number of minerals can potentially form. The mineral formation can also be impacted by other

substances than the main constituents, favoring specific minerals or conformations of the crystals.

3.1.1 Alite (C3S) Alite is as mentioned responsible for the majority of the strength development during the first 28-days.

It reacts quickly and generates a moderate amount of heat during the hydration. As can be seen in

Figure 2 it is formed in the late stages of the kiln and requires high temperature for the formation.

While typically written C3S, industrial Alite incorporates other compounds in the lattice. In industrial

clinker, typically 3-4% of Alite is substituent oxides, these include MgO, Al2O3, Fe2O3 and SO3 as

well as alkalis. [8]

3.1.1.1 Formation

Alite is formed in the kiln, when Belite (C2S) in the melted material reacts with CaO. The formation

takes place in the area of highest temperature in the kiln and the Alite is thermodynamically unstable

at lower temperatures, requiring fast cooling. [2]

Below 1,250°C during equilibrium cooling C3S decomposes into Belite+CaO, this decomposition is

slow and under 700°C imperceptible. [8]

3.1.1.2 Forms

There are different forms of Alite present in the cement, these are formed at various temperature and

different forms are stabilized by other chemical compounds. The T forms are triclinic and are formed

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at the lowest temperatures, these are also the most hydraulically reactive. M means a monoclinic

structure and R is rhombohedral. [8] [12]

The reactivity of the different forms typically increases from T1 with R being the most reactive

according to [12]. However, there are some controversy on this topic.

𝑇1 ↔ 𝑇2 ↔ 𝑇3 ↔ 𝑀1 ↔ 𝑀2 ↔ 𝑀3 ↔ 𝑅

Incorporation of substitute ions as well as temperature determine the stabilization of the various

configurations. The forms in clinker typically approximates to a mixture of M1 and M3, and in this

project these are the configurations measured. [8]

M3 is stabilized by MgO and increasing SO3 stabilizes M1, and R is typically stabilized by F- or Sr2+.

However, as mentioned higher temperature is also required for formation of more reactive forms. [8]

[12] [13]

3.1.1.3 Size

Slow formation of Alite in the kiln yields larger crystals and more perfect crystals. This is not

beneficial for the reactivity of the clinker and larger crystals also require more energy for grinding. [1]

3.1.2 Belite (C2S) Belite reacts more slowly compared to Alite and is not a major contributor to the strength during the

first 28 days. However, Belite is important as an intermediary as it reacts with CaO to form Alite. For

that reason a high Belite content may have a negative impact on the 28-day compressive strength as

well as on the early strengths if it replaces Alite. [1]

3.1.2.1 Forms

Belite has several polymorphs: α, α’H, α’L, β and γ. In industrial clinker, β-Belite is the dominant form

and is similar to the α forms in configuration. γ-Belite differs significantly from the other

configurations, being less dense and causing cracking of β-Belite in a process known as dusting. [8]

Transformations between the forms take place at different temperatures according to the following

scheme.

𝛼 ⇆ 𝛼𝐻′ ⇆ 𝛼𝐿

′ ⇆ β → γ

The α and α’H transformation takes place at 1,425°C, α’H and α’L transformation takes place at

1,160°C, α’L to β takes place at 630 - 680°C and the reverse at 690°C. β to γ takes place below 500°C

and between 780 - 860°C γ is transformed to α’L. [8]

3.1.3 Aluminates (C3A & C4AF) The aluminates react similarly during hydration and contribute little to the compressive strength of the

cement. However, it speeds up the setting of the cement paste and can lead to “flash setting” where the

paste hardens decreasing the workability of the paste. When the cement is hydrated, C3A and C4AF

react with sulfate to form ettringite which turns into small needle-like structures in the liquid phase of

the mixture. The ettringite layer forms a cover and hinders the further hydration of the aluminates, thus

slowing the setting. [2]

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Figure 5 - Ettringite and calcium hydroxide [4]

The structure of the ettringite (AFt) is shown in Figure 5 along with the structure of Calcium

Hydroxide (CH).

3.1.3.1 Aluminate (C3A)

Aluminates are formed in the kiln, depending on the Al2O3 content of the kiln feed. Pure C3A only has

one configuration: Cubic. However, through incorporation of other compounds into the lattice

orthorhombic and monoclinic configurations are possible. [8]

Figure 6 - Impact and limits of Na2O and Fe2O3 on polymorphism [13]

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As with Alite and Belite other compounds are substituted into the mineral lattice impacting the crystal

forms, key ones being Fe2O3 and Na2O. Substitution of Aluminum by Na+ plays a key role in the

polymorphism of C3A, as shown in Figure 6. Fe3+ will only have a minor impact on the polymorphs

obtained. [13]

The main C3A forms present in the clinker is cubic and orthorhombic. Of these, orthorhombic C3A

reacts quicker than cubic C3A. [6]

3.1.3.2 Ferrite (C4AF)

The amount of Ferrite formed during the clinker burning depends on the level of Fe2O3 in the kiln

feed. Ferrite is not reported and compiled in the data set used for this project, however Ferrite reacts in

a similar manner to that of Aluminate on hydration. The Ferrite reaction is slower than that of

Aluminates but the end results of AFt and AFm (as long as sulfates are present) are the same, although

with higher iron content in the crystal lattices. [2]

3.2 Minor constituents In addition to the main minerals, several other minerals and compounds are found in the cement.

3.2.1 Set accelerators Several chemical components can act as set accelerators, including the alkali metal salts, chloride and

nitrides and nitrates. In addition to these there are organic compounds that can act as set accelerators,

however, these are not further explored in this project.

3.2.1.1 Alkali metals (K and Na)

Similar to the aluminates, alkali content in the cement can speed up the Alite reaction. This can make a

significant difference and improve the early strengths. However, alkali content typically has a negative

impact on 28-day strength. [2] [8]

The most notable Alkali salts are the alkali sulfates. Alkali sulfates have different impacts on the

clinker reactivity, Langbeinite most beneficial, Arcanite medium and Aphthitalite is undesirable in the

cement. K2O can also incorporate into the Alite lattice which negatively impact the clinker reactivity.

To control the amount of soluble alkali in the clinker, sulfate levels are controlled and Degree of

Sulfatization (DoS) is used as a measure. [12]

𝐷𝑜𝑆 (%) = 77.41 ∗ 𝑆𝑂3

𝑁𝑎2𝑂 + 0.658 ∗ 𝐾2𝑂

Formula 3 - Degree-of-Sulfatization

Na+ is also found in the C3A lattice substituting Aluminum, the increased content of this will impact

the aluminate forms found in the clinker as shown in 3.1.3.1 Aluminate (C3A). Increasing Na+ into the

lattice will increase the hydration rate as the C3A takes on orthorhombic or monoclinic configurations.

3.2.1.2 Chloride

Calcium chloride CaCl2 is commonly used as a set accelerator and increases both the rate of hydration

and the heat evolution. [2]

Cl- containing salts accelerate the setting differently depending on the cations, where Ca2+ is one of the

strongest accelerators. [2]

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3.2.1.3 Free CaO

Free CaO (free lime) will decrease the setting time for the cement and is the CaO that has not reacted

with other compounds during the clinker burning. However, at high levels it also contributes to cracks

(unless lime saturation factor is low) and expansion of the concrete and should for that reason be

controlled. A low free lime content is also an indication of over-burning the clinker, meaning that an

unnecessary amount of energy has been used for the burning of the clinker. Optimal levels of free lime

are around 1.5% according to Truedsson. [1]

3.2.2 Sulfur The sulfur content in the cement is important, as can be seen it controls the amount of soluble alkalis

and is a controlling parameter for the aluminate reactions. Sulfur content needs to be balanced for

optimal cement performance.

Sulfur is introduced into the cement both through the clinker and from the gypsum which is discussed

later. For environmental reason, keeping the sulfur bound in the clinker reduces the gaseous sulfur

emissions from the plant and is therefore preferred to some extent. The sulfur content in the fuels

varies between fuels and can therefore be managed by controlling the fuel mixture to the kiln and

calciner as well as the temperature and oxygen levels in the kiln.

3.2.3 Portlandite While it forms naturally during the hydration of Alite and Belite, Portlandite present in the cement

before hydration is a sign of prehydration of the cement, where the cement has been subjected to water

during production or handling.

At Cementa the mills are cooled through water injection. Most of this water is evaporated before

coming into contact with the cement as the temperature in the mills are in excess of 100°C, however

depending on the effective spray of water and the mill temperature some water can come into contact

with the product creating Portlandite. [6]

3.2.4 Zinc Zinc have a positive impact on the clinkering process as it stabilizes the Alite phases. Although it has a

significant negative impact on the properties of the cement and reduces the cement 28 d strength even

at low levels. [8] [2]

3.3 Gypsum, Limestone & Fly-ash Added at the milling stage (into the mills for gypsum and limestone and after milling before storage

for the fly-ash) these materials all play various roles in the cement.

3.3.1 Gypsum During the milling process, the gypsum originally CaSO4·2H2O (di-hydrate) is to varying degrees

dehydrated to CaSO4·0.5H2O (hemi-hydrate). Compared to di-hydrate gypsum, hemi-hydrate

dissolves faster. The gypsum is quickly solved upon hydration to release Ca2+ and SO42- into the

liquid. SO42- reacts with the aluminates to form ettringite, controlling the rate of the setting of the

paste. The formation of ettringite also prevents a phenomenon known as flash setting, where

premature stiffening of the paste occurs as a result of formation of secondary gypsum in the case of

low C3A content or formation of calcium aluminate hydrates or monosulfate (AFm) if the dissolved

gypsum content is too low. [13]

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3.3.2 Limestone Limestone is added as a way to reduce the clinker fraction of the cement. Limestone contains mainly

CaCO3 which has various impacts on the cement. During hydration, the CaCO3 dissolves slowly and

the main reactions occur at the interface between the liquid and solid. It reacts with C3A and also

speeds up the C3S reactions. The limestone particles also provide nucleation spots and fine particles

give a good and dense structure increasing the strength. [1] [2] [6]

3.3.3 Fly-ash Fly-ash is as mentioned a by-product from coal burning processes, and two main types of fly-ash are

available: Calcareous and siliceous (calcium rich or silica rich). It is a common material for use in the

cement industry as the pozzolan nature of the fly-ash means that it reacts during the cement hydration

and contributes to the strength. Fly-ash addition helps reduce the clinker content of the finished

cement. [2]

Fly-ash is added to the BAS-cement as well as other products. The type of fly-ash used in BAS-

cement is siliceous fly-ash which mainly contains reactive SiO2 and Al2O3. The fly-ash mainly

consists of amorphous compounds, however it does contain some crystalline components and the

reactivity of these are disputed. [8]

The quality of the fly-ash varies depending on the process it originates from and the type of and source

of the coal being burnt. Chemical composition and particle sizes will impact the reactivity of the fly-

ash and its eventual contribution to the strength development. Fly-ashes with significant quantities of

materials above 45 µm have exhibited poor quality in other studies. [2]

3.4 Hydration As the cement is hydrated (mixed with water), reactions in the mixture form different compounds. It is

a complex process with many parameters that impact the progression of the hydrations reactions.

3.4.1 Calcium-Silicates reactions The hydration of Alite and Belite forms C-S-H, calcium silicate hydrate (CaO ∙ SiO2 ∙ H2O) as well as

Portlandite (CH).

3CaO ∙ SiO2 + H2O → 1.7CSH + 1.3CH

Formula 4 - Alite hydration reaction

2CaO ∙ SiO2 + H2O → 1.7CSH + 0.3CH

Formula 5 – Belite hydration reaction

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Figure 7 - 1: Hydration of C3S after 5 min. 2: Formation of needle shapes of CSH after 16 h. 3: Needles up to 900 nm in size 21 days [4]

Alite and Belite (C3S and C2S) reacts with water to form C-S-H (Calcium silicate hydrate) and

Portlandite (Ca(OH)2). The strength of the paste comes from the C-S-H which has a fiber-like

structure which grows into each other forming networks. The development of these needles can be

seen in Figure 7. C3S is responsible for most of the strength for the first 28d and C2S for the strength

developed after that, with C3S being responsible for 96% of the strength development for the first 7d,

78% of the first 28d and 45% after one year. [1] [4]

The aluminates (C3A and C4AF) react quickly as the cement is hydrated and gives generates heat. The

aluminates do not directly contribute to the strength of the cement and an uncontrolled reaction can

lead to flash setting of the cement. However, as mentioned, the reaction of C3A with water stimulates

the hydration reactions of C3S and C2S and reduces the setting time. C3A can increase the water

demand for the hydration. [1] [4]

Free lime and alkali sulfates also stimulate the early strength development of the cement. However,

high levels of free lime can lead to cracks in the concrete and while the alkali sulfate stimulates early

strength, it reduces later strength. Free lime is formed when there is a surplus of burned lime or

incomplete homogenization of the raw meal as burned lime CaO reacts with C2S to form C3S. [1]

3.4.2 Aluminate reactions Upon hydration the Aluminates react quickly and can form a multitude of compounds depending on

the presence of other components. The reactions of C3A and C4AF are similar, with C4AF introducing

Fe-ions into the mixture. Out of the C3A configurations, the cubic C3A will have the highest hydration

rate. [2]

The number of compounds that the Aluminates can form are numerous and the formations depend on

the presence of other compounds. Main phases formed from the Aluminates are AFm (Al2O3-Fe2O3-

mono) and AFt (Al2O3-Fe2O3-tri). The general formulas for these can be written

[Ca2(Al,Fe)(OH)6]·X·xH2O for mono and [Ca3(Al,Fe)(OH)6·12H2O]2·X3·xH2O for tri phase. [8]

Illustrating the differences between these two phases, the general formula for an AFm phase can be

written C3(A,F)·CX2·yH2O where the ‘mono’ refers to the single CaX2 unit. X denoting an anion and

the most common in cement hydration is OH-, SO42- and CO3

2-. Similarly for the tri phases the

C3(A,F)·3CX·yH2O and tri referring to the 3CX unit. [8]

Ettringite formed with SO42- from gypsum surrounds the C3A crystals, forming an impermeable layer

which hinders further reaction of C3A. [2]

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3.4.2 Water/cement ratio A key parameter to control when hydrating the cement is the water-to-cement ratio or w/c-ratio.

Different cement types have different ideal w/c-ratio depending on many parameters like fineness and

chemical content. Higher w/c-ratios increases the workability of the paste but may lower the final

strength as pores of water can form leading to crack formation later. A low w/c-ratio may lead to un-

hydrated material and lower workability of the paste. This is illustrated schematically in Figure 8.

Figure 8 - Water/Cement ratio [4]

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3.4.3 Progression

Figure 9 - Cement hydration progression [14]

By following the rate of heat evolution the progression of the hydration can be followed. As can be

seen in Figure 9, the aluminates react quickly and form ettringite (AFt). The AFt forms needle like

structures in the liquid phase, impacting the rheological properties of the paste. [4]

As cement is mixed with water, a solid and a liquid phase is formed. The gypsum is dissolved into the

water (giving Ca2+ and SO42-) as well as the leaching of other compounds such as alkalis into the liquid

phase from the cement. [8]

Small particles (<3 µm) also dissolve quickly and typically only give rise to temperature change,

however, most of the particles below 3 µm is the gypsum and limestone addition. [1]

The sulfate concentration decreases as the ettringite formation continues, the formation of

monosulfates (AFm) takes place. This is seen as a second “peak” in heat evolution. [13]

3.4.4 Pozzolan reaction The fly-ash as a pozzolan material, reacts with Ca(OH)2 during the cement hydration to form C-S-H.

The reactivity of the fly-ash is affected by several of the physical and chemical properties of the fly-

ash. Studies have used lime consumption tests for analyzing the fly-ash reactivity, these show that

finer fly-ash reacts quicker and that the fly-ash mainly reacts during the first 8-15 days after hydration.

[15]

The pozzolan reaction involves the attack of OH- ions on SiO2 or SiO2-Al2O3 compounds in the fly-

ash to form C-S-H. The added SiO2 from the fly-ash will decrease the ratio of Ca/Si content in the C-

S-H. The aluminum released will also be incorporated in the C-S-H as well as possibly form AFm. [8]

3.5 Strength development & Setting time The strength development and the setting time is determined by the hydration process. However, the

various properties of the cement will impact and contribute to the strength development in different

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ways over time. In general the properties of the various impacting parameters have been discussed

above.

3.5.1 Setting time The setting time of cement paste is important to control with regards to the handling qualities of the

paste. Setting time is below 200 min for the cement types studied in this report with setting time for

SH significantly shorter than for BAS.

Normal setting of cement is mainly caused by C3S reacting to form C-S-H and C3A reacting to form

AFt. It also depends on the gypsum content, as the dissolution of CaSO4 to Ca2+ and SO42- is required

for the formation of AFt. [13]

3.5.2 1d strength The first compressive strength is measured after 1 day, the strength at this point depends mainly on the

hydration of C3S to form C-S-H. However, indications of C4AF possibly contributing to strength

development is also present in the literature. [13]

The amount of formed C-S-H will be impacted by other factors in addition to the C3S content. A finer

cement gives a higher reaction surface area for interactions between the C3S leading to the increase in

the amount of C3S that has reacted. The amount of liquid and the content of other chemical

compounds like aluminates will also impact the early strengths. Aluminates accelerate the strength

development to a degree, however can have adverse effects if the sulfate content is inadequate. [13]

[2] [1]

3.5.3 28d strength After 28 days the formation of C-S-H from Alite is still the main contributor to the strength. However,

at this point the fly-ash has also reacted to form C-S-H, and some of the Belite have also reacted.

3.6 Multivariate analysis Modelling and prediction aims at formulating a model explaining the variance in the output parameters

(Y) using input parameters (X). In this project, in addition to the Neural Networks model, classical

multivariate analysis software and tools have been used.

Some variations may exist between different software platforms and the theory below is all based on

the version of these methods used in Excel and Unscrambler.

3.6.1 Multivariate analysis & regression The purpose for using traditional multivariate analysis in this project is the information and increased

understanding of a data set which can be extracted using these methods. Principal Component

Analysis & Regression (PCA), Partial Least Square (PLS) and Multiple Linear Regression (MLR) are

all available in the software tools used in this project. These methods are further explained in

Appendix x.

The tools used in the traditional multivariate analysis in this project all create linear models. A

coefficient is found for each input parameter X and the sum of these will give the output parameters.

Additionally, in many cases a constant (β) is also found, representing the level around which the (Y)

parameter varies.

𝑌 = 𝛽 + 𝑐1𝑥1 + 𝑐2𝑥2 + ⋯ + 𝑐𝑛𝑥𝑛

Equation 1 - Linear multivariate model

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The coefficients for each parameter acts as weights for a parameter, regulating and matching the

degree to which it impacts Y.

3.6.2 Excel regression tool Excel has a built-in function for multiple regression analysis with several variables. It has some major

limitations, it can only account for 16 variables and produce 1 output for each run. It produces a linear

model and has previously been used at Cementa for predictions of 28-day strength. [11]

The benefits of the tool in Excel is the availability, however it has serious limitations. It can only

handle 16 parameters, and while this is plenty for the final model, it reduces the possibility of using

this for parameter selection as the number of variables for each sample is well above 16.

Parameter selection could be done by running several iterations using the tool and the results include

values indicating the importance of each variable. However, this is a less robust way compared to the

methods in Unscrambler.

3.6.3 Partial Least Squares Partial Least Squares is a multivariate analysis method used for connecting an input X to an output Y.

In this project Partial Least Squares regression is used, creating a model for connecting X to Y. The

PLS regression also provides additional information on the data set. PLS regression is a common tool

in chemo metrics. PLS regression is described in more detail in Appendix x. [16]

The parameters used in this project are measured in different units and vary wildly, for that reason

when running PLS the input data can be scaled. The variables are scaled to “unit variance” by dividing

the variable with the standard deviation of that variable. This allows for evaluation of the importance

of the variables. [16]

As mentioned, from the PLS analysis, in addition to the model, other information on the data set can

be found. This information include insight on the samples and the variables in the data set, including

variable and sample impacts as well as residuals.

The variable importance is in the PLS regression in Unscrambler given through Uncertainty Analysis.

In essence, this identifies the variables whose impact cannot be attributed to chance by analyzing the

uncertainty in the estimations of the variable impacts. This is a major benefit to the work of reducing

the number of variables used in prediction in future steps.

The influence of samples as well as residuals for samples are also found using the PLS method.

Samples with large influence as well as samples with large residuals should be reviewed: Large

residuals mean that the model to a higher degree fails to explain the output for this sample and it may

be an outlier or a result of some error in the data set.

Samples with high influence on the models also may impact the model negatively. While having only

one or a few samples at the extreme ends of the interval means the increased influence of these, it may

not benefit the model.

In Unscrambler, cross validation can be used to check the performance of the formulated model. This

involves dividing the data into several sets removing one set of samples from the training set, using the

model to predict the Y for these samples and comparing it to the measured Y. This is then repeated

until every set has been tested. Several methods of selecting the samples used for validation is

available, however, allowing Unscrambler to select samples randomly out of the set is sufficient for

this project as this model will not be used for prediction. [17]

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3.7 Neural network

Figure 10 - RBFN Neural Network explanation [18]

An Artificial Neural Network (ANN) as used in the model developed by HTC works by forming

networks of “neurons”. Simulating the learning processes found in biology, the ANN is trained using a

training set and the trained ANN can then be used for prediction. The neurons are in essence

mathematical weights for each of the input parameters. The amount of layers of neurons varies

between the various models and applications of ANNs.

The process of teaching the neural network models is also reminiscent of the process of learning found

in nature. Teaching the model is done by giving it known data. In the case of this project, the known

data would include the parameters which affect the 28d strength and the experimentally determined

value of the 28d strength. The model “adapts” to this data and when it is later given only the

parameters it can predict the 28d strength. [18]

Radial Basis Functional Network is the type of ANN most used in this project. Each neuron has a

weight and the impact of each neuron depends on the distance of the input from the neuron. As can be

seen in the “Basis function” in Figure 10, larger distance between the “neural center” and the input x

will reduce the influence of this neuron on the output.

RBFN has a hidden layer containing the neural weights as well as the basis functions and the training

is not monitored by the user. While robust and easy to use, the model for this reason provides limited

information regarding variable and sample impacts.

In the model used in this project, several of the model parameters such as number of neurons and

kernel width can be adjusted by the user. This allows the user to achieve better performance of the

model without adding samples to or changing the data set.

3.8 Bias-Variance The possibility of accurately predicting samples above or below set boundaries are key to identifying

issues with the cement. However, ANN accuracy tend to decrease towards the extremes of the interval

due to the bias of the models.

This bias needs to be balanced with the variance, a high bias tends to mean a low variance and this can

be described as a tradeoff between the degrees to which the model learns the training set versus the

degree of accuracy for the predictions.

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Figure 11 - Bias vs. Variance [19]

High bias means that the model fails to account for variations in the data. While Figure 11 provides a

highly simplified view of the issue, it demonstrates the key balance between overfitting and

underfitting.

A high variance (overfitting) model will include the noise of the data, it also reduces the bias of the

model: This will provide good correlation for the training set, however the accuracy of the prediction

will worsen.

The issue of bias and the ANN tendency to underestimate high values and overestimate low values

have been discussed in the medical field along with possible solutions to this issue. [20]

3.8.1 Sample stratification

Figure 12 - Distribution of samples 28 day strength BAS-cement from Unscrambler

As can be seen in Figure 12, the distribution of samples over the interval is not even over the entire

span. The majority of samples are in the mid-range of the span which can lead to problems with bias.

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Sample stratification involves dividing the samples into ranges and compiling a set with a more even

distribution of data points between the ranges. Duplication has been tried where the samples at the end

points of the interval are replicated to artificially even out the distribution. Unfortunately this reduced

the precision in the center of the interval without sufficiently addressing the issue. [20]

In the case of sample selection, picking out samples equally spaced over the interval will also remove

the large focus on the center samples. However, an approach where sample selection is used requires

the data set to be sufficiently large and include sufficient number of samples at the extreme ends of the

interval.

3.9 Sustainability As mentioned, Cementa has a target of the cement being carbon neutral by the year 2030. While

several different measures are taken to achieve this, this project mainly touches on the cement strength

and quality. This combined with the production costs are limiting factors in the work towards a more

sustainable production.

3.9.1 Reduced clinker content in the cement As the clinker burning stage is both costly and the source for most emissions from the process,

reducing the clinker share of the cement is one of the actions already taken. BAS-cement with the fly-

ash addition as well as the limestone addition to the products are such examples. Depending on the

material, the addition can take place in various locations in the process. While a fine material such as

fly-ash can be added after the mill, limestone is added to the cement mills and milled with the cement.

Reducing the clinker share in the cement can also provide a financial benefit, however this depends on

the cost of the material used. An added difficulty regarding this is the fluctuations of the supply,

demand and in the end the cost of the material. As regulations and agreements define the limits for

variations in the addition of these materials, quality also determine the possible variations.

Addition of these materials will impact the cement properties, and for that reason the addition has to

be balanced against other properties of the cement.

3.9.2 Reduced amount of virgin limestone Alternative materials can also be added at the start of the process, adding materials that does not

require calcination reduces the CO2 emissions from this step. These additions will impact the clinker

quality and similarly to the addition of materials to the cement mills or to the finished product the

addition has to be balanced against the final product quality.

Addition of slag products containing calcined limestone is done to some extent today at Cementa,

reducing the amount of CO2 released per unit of cement.

3.9.3 Process optimization Over-grinding and over-burning present significant challenges in the cement production. Working

towards sustainability, decreasing the thermal and electrical energy demands per unit of produced

cement will be a step in the correct direction.

3.9.3.1 Alternative fuel usage

Even though overall thermal energy demand per unit of produced clinker has decreased, the amount of

fuels needed are still a major source of the emissions from the cement production process. [21]

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Working with the current process at Cementa, work on increasing the share of alternative fuels,

particularly the bio-based alternative fuels, is currently under way. As mentioned, the current

alternative fuels are RDF (refuse derived fuels), tires and waste oils.

The amount of alternative fuels which can be used depends on the quality of the fuel, and the

alternative fuel varies in quality depending on the source and over time. RDF typically have a lower

energy content and a higher content of chlorides and alkalis compared to the fossil fuels.

3.9.3.2 Over-grinding

A finer product generally means a product with higher strength and a reduced setting time as discussed

previously in this chapter. While these are desirable qualities, grinding the materials requires large

amounts of electrical energy. A finer product with a large fraction below 3 µm will also be highly

reactive but contribute little to the final compressive strength. [1]

Balancing the fineness of the cement against variations in clinker reactivity or in other ways reduce the

fraction of material ground to unnecessary fineness while still maintaining good compressive strength

may be beneficial from a sustainability point-of-view.

3.9.4 Concrete carbonation Concrete carbonation, the absorption of CO2 into the finished concrete structure is another method for

decreasing the carbon footprint over the lifespan of the cement.

The amount of CO2 that can be absorbed by the concrete structure depends on several factors. The

physical properties of the concrete such as pore sizes will have a major impact as well as the CO2

concentration in the air. This means that the w/c ratio will impact the amount of carbonation taking

place as a higher w/c ratio will lead to increased number of pores. A lower pH-value will also benefit

the carbonation rate, which in turn means that the addition of fly-ash which consumes a part of the

formed CH will benefit the carbonation. However, for fly-ash, the formation of new C-S-H can block

capillary pores which in turn negatively impacts the carbonation rate. [22]

4. Procedure The work flow in this project is cyclic. The first step involves studying and gathering information on

the theoretical aspects of this project, including cement hydration and clinker mineral composition etc.

After this step, data has been collected using files compiled by the quality engineer in Slite (i.e. Tore

Jönsson). Preparation of data involves formatting and looking for typos etc. in the data. Data analysis

is done through the traditional multivariate analysis methods and the results are later used in the ANN

model to create an index. The index and the results from this is validated through different methods.

After this, depending on the results from the previous steps, return to the theory, data collection etc. to

both explain the results and possibly improve the index.

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4.1 Literature study At the start of this project, a literature study was produced with the aim to increase the knowledge

about the theory behind cement performance as well as compiling this information for later use in the

project. Several parts of the literature study were used in the background and theory sections of this

report and the literature study in its complete form can be found in Appendix.

4.2 Data collection and preparation Data for this project is already available in an excel file containing the analysis results for all

shipments of the various cement types. This file is updated regularly and the data forms the basis for

the further work.

Before it can be used in the project, the data needed to be prepared. Unscrambler as well as the ANN

model requires data formatted in a certain way, and the data from the excel file is therefore stored and

formatted in separate files. At this stage a rudimentary error analysis is conducted, however, excel

sheets provide limited possibilities for identifying issues.

4.3 Traditional Multivariate analysis Traditional multivariate analysis provides, in contrast to the Neural Networks model, a large amount

of information regarding the data set. As described in section 3.6 Multivariate analysis, information on

the impacts of samples and variables can easily be extracted using these methods.

In Unscrambler the Partial Least Squares tool is used for the analysis of the data. This creates a PLS

regression model which can be used for prediction, however, only the additional information on the

data is used. Cross-validation is also used to check the models performance as well as a foundation for

the uncertainty analysis.

Theory

Data Collection

Data preparation

Data Analysis

Neural Networks

model

Validation

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The most significant benefit with using the PLS method in Unscrambler is the uncertainty analysis.

This uses the different sub-models produced during the cross-validation and the determined

coefficients for each of these sub-models to create a variable which represent the variance of the

coefficient between the sub-models. A t-test is used to determine the significance of each coefficient

and uncertainty limits (2 std. deviations) gives the “uncertainty limits” for each parameter. If the

uncertainty limits (represented in Figure 13 as error bars) do not cross the zero-line, the parameter is

determined to be significant. [17]

Figure 13 - Uncertainty analysis results from Unscrambler

The uncertainty analysis uses the uncertainty of the coefficient determination to determine if the

variable has an impact that cannot be explained by chance.

4.3.1 Excel Multivariate regression in Excel was used at the start of the project, however as it can only handle 16

parameters it could not be used for parameter selection without running several iterations and picking

the most significant variables each time. The results give the coefficients for a linear model which can

be used for prediction of future value.

4.4 Choosing parameters Overall in excess of 40 parameters are analyzed for each cement type, however for a robust and usable

model the amount of variables used needs to reduced. A target of roughly 10 parameters for each

index is used in this project. The process of choosing parameters has been done in steps.

4.4.1 Initial exclusion To the highest degree only the analysis results from the process laboratory were used and for that

reason most of the parameters analyzed at CR were excluded. While CR generally has better precision

of the analysis results, their exclusion will increase the usefulness of the indexes as it can be used not

only on samples from shipments but also for samples collected during production.

In cases where the same parameter is analyzed several times through different methods at the process

laboratory, the most reliable has been selected. This mainly includes SO3 which is analyzed at the

process laboratory both through XRF and XRD and in this case the XRF data has been used.

4.4.2 Uncertainty test One method to narrow it down to the most significant parameters which can provide a strong model is

Unscrambler’s “Uncertainty analysis” which has been used during the PLS regression analysis runs.

However, the identified parameters from the uncertainty test does not necessarily provide the best

model as the identification is based on the data used in the PLS analysis. There are several factors to

take into account when evaluating the parameters identified, for example the accuracy of the analysis,

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the variance of the parameter as well as the theory on strength development. For that reason, the next

step has been manual selection.

4.4.3 Manual selection The uncertainty test is purely mathematical and the results will not necessarily include all the

important parameters or exclude all unimportant. Results from the uncertainty test may also indicate

more or less parameters than is desirable. For these reasons, the theoretical impacts of the parameters

has been used for manual selection of the final parameters with the results from the Uncertainty test as

a starting point.

During the manual selection, the target has been to include the variables that supply the most amount

of useful information to the model. A few of the following issues also have been identified during this

step

4.4.3.1 Connected and correlated parameters

There are several dependencies and connections between the parameters in the data set, this needs to

be accounted for when selecting the parameters for the model. Having the same property of the cement

used twice in the model is not only redundant but also put an increased amount of weight on that

property for the model. It can also increase the amount of noise and decrease the robustness of the

model.

Clear cases for this would be the configurations of Alite, M1 and M3. While the content of these

phases will impact the strength, the content of these phases will increase with the total content of

Alite. For that reason, Fraction_M1 which describes the share of the Alite in the sample that is in M1

configuration provides more useful information.

4.4.3.2 Not identified critical parameters

While the analysis in Unscrambler generally identified most of the parameters that can be considered

critical for cement strength, some additions have been made to guarantee the index performance over

time. Possible additions have been considered carefully and while the uncertainty test managed to

include these parameters in the majority of cases this still needs consideration.

Examples of this is the content of Alite in the sample. Alite is as mentioned responsible for the

majority of the strength development during the first 28d, and not including this as a variable could

reduce the index’s performance in the future.

4.4.3.3 Identified unimportant parameters

To some degree captured through the connected and correlated parameters, in some cases the analysis

in Unscrambler identified parameters that should not be included in the models. This is for example

true in cases where parameters with small variations or where the content was generally zero apart

from a few samples.

Examples of this is Langbeinite and Anhydrite. While these can impact the strength, the content of

these are in many cases zero. The small number of samples containing these will therefore get unfair

importance, and if the samples containing these also have high or low strength these could be

considered by the uncertainty analysis as more important than is the case.

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4.4.3.4 Final selection

As mentioned, including the variables which provides the most amount of useful information and the

largest theoretical impact has been the target. For that reason, a final check was made using both the

correlation coefficients achieved in the indexes in the ANN model as well as manually.

4.4.4 Unknowns In addition to the parameters measured, unknown parameters will also impact the model. While

4.5 Selecting samples The sample selection phase, similarly to the data preparation, aims to provide good and useful data for

the model. However, going further than simple formatting and removing obvious errors, the sample

selection utilizes Unscrambler, the HTC model and Excel to identify issues that can impact the model

negatively. The goal is to achieve a low bias meaning a high accuracy over the entire interval.

4.5.1 Variations in laboratory equipment A key issue regarding sample selection is variations in the analysis equipment needs to be accounted

for. As calibrations and other possible sources for variations in the equipment does not occur at the

same time in both laboratories, comparing results between the laboratories may provide insight into

when major changes have occurred.

While calibrations are logged, the impact of these calibrations varies. For XRF, the impact not only

varies between calibrations but also varies between the analyzed elements. Comparing the XRF results

from CR and the process laboratory provides the following graph for Na2O in SH-cement.

Figure 14 - Na2O measured on the same samples (only SH-cement), sorted chronologically

In Figure 14 it can be seen that there is a large difference between the results for Na2O content before

the spring of 2017. The period studied is chosen as XRF results from both laboratories are available

and compiled for this period.

0,12

0,17

0,22

0,27

0,32

0,37

2016-11-26 2017-03-06 2017-06-14 2017-09-22 2017-12-31 2018-04-10 2018-07-19 2018-10-27 2019-02-04

Na2O

Na2O Na2O CR

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This information suggests that a calibration was conducted in the spring of 2017 with a large impact

on the results. Using samples both before and after this calibration can impact the index and provide

conflicting results on the statistical impact of Na2O on the strength development.

Such clear impact of that calibration cannot be seen on other elements. Although for SO3, comparing

the results from carbon-sulfur determinator with the results from the process laboratory, a consistent

difference between the results can be seen. Consistent/constant errors have less impact on the model,

as the error becomes accounted for in the process of constructing the model.

4.5.1 Bias As most samples are in the center of the interval with occurrences decreasing towards the extremes of

the interval sample selection was tested. In this case the sample selection was conducted in

Unscrambler, picking equally spaced samples over the entire interval. It was only possible to do this

for BAS-cement due to the small data set for SH-cement.

Figure 15 - Histogram for 1d strengths BAS-cement

Figure 15 shows the histogram for all 1d strengths for BAS-cement in the data set used in this project.

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Figure 16 - Histogram for selected 1d samples for BAS-cement

Figure 16 shows the histogram for the selected samples, demonstrating a more even distribution. The

reason for the still low portion of the samples at the extreme ends of the interval is simply due to the

lack of samples at these points. Removing enough sample for a completely even distribution would

reduce the number of samples too far for achieving a good index.

4.6 HTC model The final indexes will be in HTCs Neural Networks model as this is an easy to use and robust model.

Information from Unscrambler is for this reason used as a basis to form the model in HTCs model.

This includes the selection of samples and parameters.

Significant variables identified through Unscrambler for the prediction provides a starting point for the

model. As the functionality and method varies significantly between the two platforms, additional

work must be done to assure that the best combination of parameters is chosen for the final model.

To help identify good models, when the model is created HTCs model provides certain data regarding

the model, the main indication being the correlation coefficient. A correlation coefficient close to one

means a model which explains the variances in the output parameters. While only an indication, it is

helpful towards selection of parameters where the target is to maximize the correlation coefficient.

4.6.1 Functions & Procedure The model software developed by Dr. Jan Skocek at Heidelberg Technology Center contains several

different neural networks models. Most developed is the RBFN model while the 3LNN (three layer

neural network) model is still under development. For that reason, the RBFN model has been used. An

additional functionality is the multiple linear regression, this is more similar to the traditional

multivariate approach and has not been used in this project.

The model runs in excel and the data is entered into a sheet called “Data Example”. The number of

parameters and their use in the model can be specified in this sheet. The data is formatted, removing

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samples without data on all parameters used in the modelling and this formatted data is then pasted

into a separate sheet. From here, the model is run and the graphical user interface (GUI) is opened.

When running the model, it identifies samples which are potential outliers in the sense that they do not

correspond to the behavior of other samples. The user can choose to deactivate these samples or

simply deactivate the samples with the highest relative difference from the measured value for the

output parameter. A correlation coefficient as well as information on the errors between measured

values and approximated values are shown to the user in the GUI.

Approving the model the next step allows for verification of the model, the model can pick samples

randomly from the data set, removing them from the training set and then predicting the values of the

output parameters for a fairer evaluation of the model performance. The model reports on the errors as

well as correlation coefficients for both the training and verification set when the verification is run.

And in case of large errors and/or low correlation, samples can be moved from the verification set to

the training set.

The model also allows for adjustments on several parameters of the model, including the number of

neurons per sample, punishments for large neural weights etc. Changing these parameters allow for

balancing the variance and bias. The model can also optimize these parameters automatically, however

this is a slow process when having large data sets.

4.6.2 Separate indexes for 1d and 28d As the variables used in the model vary between the 1d and 28d indexes for the cement types, the

decision of using separate indexes for prediction of the different strengths is made. While this

decreases the user-friendliness, the prediction accuracy would suffer from having both strengths

predicted in one index.

As the model uses all the variables specified by the user, for example including all variables that may

be significant for both strengths would lead to the model including the insignificant variables for

predictions of the separate strengths. This risks decreasing the index performance and robustness as it

would mean including far more variables than necessary.

4.6.3 SH-cement While the analyses from CR was included in the Unscrambler runs, the focus is on the process

laboratory analyses. However, while the data only contains 32 µm, 32-2 µm and d50 from the PSD

analysis at the process laboratory, recently 15 µm was added. As SH is a finely ground cement, the 15

µm passing percentage will provide a more interesting measure regarding the particle size. As this was

only recently added to the reports from the process laboratory, 15 µm analysis from CR can be used in

the model.

4.6.4 BAS-cement For BAS, the analyses run at the process laboratory forms the basis for the model. A coarser cement,

reported particle sizes analyzed at the process laboratory better reflect the variations in the particle

sizes between samples. The number of analyses run on BAS-cement at CR is also lower compared to

the SH-cement, further motivating limiting the variables used to those from the process laboratory.

4.6.5 Verification/validation HTCs model has a built in verification function, removing a number of random samples from the

training set and using them for verifying the performance of the model. The number of samples used

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for verification can be chosen and the choice is made by stating “on average every nth sample will be

used” where 3 will lead to that on average every 3rd sample is used for verification.

The sample selection is random, and when the selection is done samples can be returned to the training

set if the correlation is impacted to a high degree. As the selection is random, the verification is run 3

times for each of the indexes.

4.6.6 Bias issue identification The issue with bias is identified as the ANN model showed a clear tendency to overestimate the low

samples and overestimate the high samples during the verification step.

4.6.7 Bias-Variance balance Working with Bias-Variance balance is mainly done using the functionality of the model itself and the

balance is dictated by the desired functionality of the index. While in many models the target is to

achieve the lowest possible total error of prediction, in this case the ability to identify samples outside

acceptable boundaries (at the extremes of the interval) is more useful.

Looking at a typical verification set for the model, the error can be plotted against the measured

strength. This gives an indication regarding how the error will change over the interval. Plotting a

trendline in excel and using the slope and the R-squared value for the trendline provides information

on the bias of the model. A model with low bias will have a low slope and low R-squared value,

meaning that there is low correlation between the strength and the error.

To investigate the impact of the model parameters on the bias-variance balance several indexes with

identical training and verification sets are created and the error plotted against the measured strength.

The correlation coefficients of each index is also considered in addition to the slope and the R2-value

of the trendline in the figure.

A “Bias value” is calculated by multiplying the slope and the R2-value. A higher slope indicates a

higher bias and the R2-value indicates the fit to the trend line. As the R2-value decreases, the fit of the

trend line decreases and the errors are more randomly distributed over the interval. A random

distribution of the errors is desirable for this model.

While Bias-Variance balancing typically aim at the precision of the model throughout the entire

interval, in this project the samples at the extreme ends of the interval are more important to identify.

For that reason, an increased focus has been on reducing the bias of the model. Several ways of

approaching this have been used, mainly sample selection and model parameter variations.

4.6.8 Model parameters For RBFN the model parameters can be varied in the GUI, as shown in Figure 17.

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Figure 17 - GUI for model parameter adjustment in the ANN model

The theory behind the various model parameters impact on the model is described in A2.1 Radial

Basis Function Network. Option to optimize the parameters is available, however this will be time

consuming for larger data sets as it varies the model parameters and creates new models until the

optimum is reached. For SH-cement this has proven possible within minutes but for BAS-cement and

the larger data set it is impractical.

4.7 Clinker minerals The clinker minerals are also studied separately with the aim to further increase the knowledge around

the clinker mineral impact on the strength development of the cement. While the clinker is the same,

the clinker content and several other parameters are different between the cement types. As the content

of the various clinker minerals is reported as share of the total sample, actual content of clinker rather

than the quality of the clinker will have a large impact if studying the different cement types together.

As each cement type needs to be studied separately, SH-cement should be chosen. While a small

number of samples are available, the variations in the quality of the fly-ash introduces an added

unknown into the BAS-cement. However, XRD analysis on SH-cement is currently less accurate than

on BAS-cement due to the fineness of the cement.

4.7.1 Analyzing clinker mineral impact The final properties and composition of the cement is not only the result of the clinker content and

quality but also depends on the cement milling and the mixing of materials at that stage. While an

ideal scenario would include constant quality and quantity of the additives and large variations in the

clinker quantity and quality, these types of analyses has not been done on a scale where the data set

size would support using the methods used in this project. These types of investigations are time

consuming and costly as the cement has to be milled in the laboratory in sufficient quantity for

analysis.

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Certain analyzed parameters of the cement are theoretically however, only a result of the clinker.

Specifically the contents of minerals formed during the clinker burning like Alite, Belite and

Aluminates.

4.7.2 Procedure

Figure 18 - The GUI for creating scenarios in the ANN model

The impact of the clinker minerals can be found by using the scenarios function in the ANN model.

This allows for variation of only selected parameters throughout a range specified by the user, fixing

the other parameters to set values. The user can also specify the number of levels for which scenarios

will be created, the default number of levels is three. A screenshot showing this functionality is shown

in Figure 18.

Multiple parameters can be varied at the time, however, the model will in those cases calculate every

possible combination of these parameters depending on the number of levels selected. This number of

scenarios calculated will for that reason be the number of levels to the power of the number of

parameters selected.

4.8 Additional work Not part of the main procedure, the following work has been conducted to either simplify the project

work or to provide new tools for future work in the area.

4.8.1 Macros In Excel, Visual Basic for Applications (VBA) can be used for coding additional functionality to

Excel. This has been done for two tools that added some functionality that was needed for this project.

Basic knowledge of programming as well as online resources (forums etc.) was used in the

programming of these macros. For the function “IsFileOpen” this is available on Microsoft Support

forum and is copied from that location.

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4.8.2 Anläggningsindex The current index for Anläggningscement has been evaluated using the insights gained during this

project, and a new index produced using the procedure in this project has been proposed to Cementa.

5. Results and Discussion Overall, within this project four indexes for estimating the compressive strengths of BAS and SH-

cement has been produced. A key result in this project is also the procedure used to develop the

indexes, as will be shown in this section, the indexes produced show results deemed adequate.

The results regarding clinker minerals show that the Alite, as expected, has a major positive impact on

the cement strength development. It also shows that the procedure used in this project can be used in

the future to develop indexes for other cement types and other parameters in the cement manufacturing

process.

The main issues include the bias of the indexes, data set sizes and the model functionality.

Mentioned as an objective with lower priority, prediction of setting time has been tested. However, the

setting time varies over a large interval and the setting time data is not continuous over the interval,

rather being reported as 5 minute steps.

5.1 Verification Verification has mainly been done using the built-in feature in the ANN model, where the software

selects a random set of samples (the number of which can be controlled by the user) and removes these

from the training set.

Verification is done through the built-in verification feature in the ANN model which selects a random

set of samples, removes these from the training set and predicts the strengths of these and comparing

to the known value. As the sample selection is random, the distribution of these varies between runs

and with that the verification set can indicate different index performances between different runs.

Figure 19 - Verification sets for 2 model runs from ANN model

y = 0,4639x - 27,097R² = 0,3857

y = 0,3627x - 21,302R² = 0,2246

-6

-4

-2

0

2

4

6

53 55 57 59 61 63 65

Erro

r (M

Pa)

Measured strength (MPa)

Bas 28d RBFN

Error run1

Error run2

Linjär (Error run1)

Linjär (Error run2)

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Figure 19 shows the verification sets of 2 different runs of, in every other way, identical models. For

this reason the verification has been run 3 times on each of the indexes as shown in the verification

graphs for the indexes for BAS and SH.

The randomness and the differences between runs means that a roll-out time for the indexes should be

implemented where the real-world performance is evaluated. Verification sets and performances for

these runs could later be compared over time to get a better insight into the index performance.

5.2 Procedure The procedure was developed as functionality of the tools and the needs was identified. As parameter

selection must be done manually in the ANN model, using Unscrambler’s uncertainty analysis to

identify the important parameters was used.

5.2.1 Including 1d strength as parameter for 28d strength prediction The early strengths and the later strengths are highly correlated and including the 1d strength for

prediction of the 28d strength would benefit the index. However, including 1d strength means that the

index cannot be run using only data from the process laboratory.

Using predicted 1d for prediction of 28d is bad practice during modelling due to error propagation.

5.2.2 Target of 2 MPa The target of 2 MPa has been used in previous modelling work, and for good reason: It allows for

catching relatively small variations in the compressive strength. However, the uncertainty of the

compressive strength analysis needs to be considered as well.

Method ER9227, the accredited method for compression strength testing used at CR, states that the

95% confidence level (2 x total measurement uncertainty) is 9% for 1d strength and 5% for the 28d

strength. This corresponds to roughly ±2MPa for 1d strength and roughly ±3MPa for 28d strength for

these cement types. With this knowledge, the target of 2MPa should be used carefully and 3 MPa was

chosen as a target for 28d strength in this project.

5.2.3 Parameter selection The target of the parameter selection is to identify the parameters which have the highest impact on the

compressive strength. Some things has been considered during the parameter selection in addition to

what has been reported from the Uncertainty analysis.

Having parameters that are connected and to a degree include the same data puts unfair weight on the

connected quality. The model does not understand the connection between parameters and will for that

reason treat these as separate.

In addition to connections between parameters, the quality of the analysis has also been weighed into

the selection process. SO3 is analyzed both through XRF and XRD, however the general view is that

the XRF analysis provides a more accurate value and for that reason this has been selected.

On the same note, the SO3 reading from the XRF at the process laboratory is less reliable than the SO3

reading from the carbon-sulfur determinator at CR. However, for the analysis at CR fewer data points

are available and the analysis is slower, and to enhance the usefulness of the model, XRF value has

been used. In this case, the SO3 from the carbon-sulfur determinator and the XRF was compared

before and the error was to a degree systematic rather than random, and systematic errors is handled

well by the model. The comparison is seen in Figure 20 & Figure 21

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Figure 20 - Difference between Carbon-Sulfur determinator and XRF for SO3

Figure 21 - Results of analysis on SO3 on XRF and Carbon-Sulfur determinator

5.2.4 Separate indexes While the user would benefit of having the same index for prediction 1d and 28d strength of the

cement types, there are some issues with this approach. The significant variables are not the same for

both 1d and 28d as the parameters will have different impact at 1d and 28d. For that reason, separate

indexes must be made.

Predicting both strengths in one index would risk significantly reduce the performance of the indexes

and as the number of variables would need to be increased the bias may worsen.

y = -0,0002x - 0,1667R² = 0,0097

-0,5

-0,4

-0,3

-0,2

-0,1

0

0,1

0,2

0,3

0 20 40 60 80 100 120 140 160

Dif

fere

nce

(%

-po

ints

)

Sample number

Difference between XRF and CS

Difference

Linjär (Difference)

20 per. glid. med. (Difference)

3,2

3,3

3,4

3,5

3,6

3,7

3,8

3,9

4

4,1

0 20 40 60 80 100 120 140 160

Rea

din

g (%

)

Sample number

SO3 from XRF and CS

SO3_CS SO3_XRF

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5.2.5 Unscrambler models As seen in the figures from Unscrambler, the correlations coefficients for the PLS models are low in

comparison to the correlations for the ANN indexes. This demonstrates that using the PLS model for

prediction would not perform at the same level as the ANN indexes created. However, using the

additional information generated through the PLS runs have proven to give good results in the ANN

indexes.

5.2.6 Anläggningsindex While not part of this project, using the procedure described in this report a new index was proposed

to Cementa for their index for 28 d strength on Anläggningscement. Cementa has used an index for

Anläggningscement since before this project started, however, using the procedure and the lessons

learned from this project some improvements could be proposed to this index. The index currently

used at the plant is the proposed index.

As this is not part of the project, the development and evaluation of this index was conducted outside

this project and the results are excluded from this report. However, the use of this index will allow for

evaluation of possible deterioration of indexes developed in this manner and is a basis for further

study.

5.3 SH-cement For SH-cement, runs in Unscrambler indicate statistical importance of a number of variables. A full

list of variables used and additional graphs are available in appendix.

1 d 28 d

SO3_XRF 0,283 0,7105

K2O 0,1793 -0,3245

Cl 0,245 0,3676

d50 -0,3192 0

2 µm 0,203 0

3 µm 0,2087 0

15 µm 0,3888 0,4786

Alite_M3 0,2213 0

Alite_Sum 0,2327 0

Alum_cubic -0,1916 -0,1166

Alum_Sum -0,2038 -0,1588

Aphthitalite 0 -0,2983

Arcanite 0,1523 0

Belite_beta -0,2043 0

Calcite -0,1655 -0,0754

CO2_XRD -0,1664 -0,0742

Hemi-

hydrate 0,1314 0

Table 2 - Variables indicated by Unscrambler for SH-cement

Most of the variables indicated have a foundation in literature which is discussed in section 3. Theory.

However, while these provide a good starting point, further limiting of the number of variables as well

as checking for redundancy has to be made.

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5.3.1 1 day index While most of the variables identified by Unscrambler, additional reduction of variables is done.

As the variables d50, 2 µm, 3 µm and 15 µm all represent particle sizes 3 µm are not included in the

final model. 2 µm, d50 and 15 µm provides a good representation of both the amount of fines that

theoretically does not contribute to the strength development as well as the variation of the general

particle size distribution difference between different samples.

The reasoning for choosing 15 µm rather than 32 µm for SH-cement is due to this cement type being a

finer cement type. For that reason the amount of material passing 32 µm is generally high for all

samples and for that reason 15 µm provides a better indication of variations in grinding between

different samples. The variable d50 (size where 50% of particles are below this size) also provides

valuable input into the overall particle size distribution. All being correlated to some degree, however,

as the particle curve can be uneven, they all provide valuable input.

While Alite M3 is identified as significant variable as well as Alite Sum, the level of Alite M3 is

highly correlated to the total amount of Alite. In this case, to capture the potential difference which is

caused by the amount of M3 the variable Fraction M1 is included in its place. This variable indicates

the portion of Alite that is of M1 configuration and for that reason describes the variations in M1

versus M3 without depending on the total amount of Alite, which is included in a separate variable.

For aluminates, the total amount of aluminates is deemed more important than the different

configurations and to limit the amount of variables, only Aluminate Sum is included.

CO2 is excluded as this may be correlated to the amount of Calcite in the sample.

SO3 (XRF)

K2O

Cl

d50

2 µm

15 µm

Alite Sum

Aluminate Sum

Arcanite

Belite_beta

Calcite

Fraction M1

Hemi-hydrate gypsum

These variables are used in the ANN model to produce an index. This results in a correlation

coefficient of 0.941 before verification, and using the built-in verification function of the model with

the results demonstrated below. While the total data set is constant between runs, the data set is

selected randomly by the model and for that reason three runs is done for each index with the aim to

demonstrate the variations between runs.

Run 1 Run 2 Run 3

Correlation coefficient: 0.941 0.941 0.941

Number of samples in verification set: 28 27 27

Samples with error above 2 MPa: 2 0 1

Percentage of samples with error above 2 MPa: 7.14% 0 3.70%

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Table 3 - Results for produced index for SH 1 day compressive strength

Figure 22 - The difference between measured and predicted for 1d strength SH-cement from HTCs model

Table 3 shows that in all three runs, the number of samples in the verification set with a difference

between measured and predicted above the set threshold at 2 MPa are below 10 %. The errors are

visualized in Figure 22 (measured value minus predicted). In Figure 22 the trendlines demonstrate the

indexes tendency to overestimate the strengths of samples with low compressive strength and

underestimate the strengths of the samples with high compressive strength (bias).

However, in the case of SH-cement the data set is small, this means that the verification set is also

smaller than desired.

5.3.2 28 d index For the 28 d strength index, the results from Unscrambler yielded very few variables as significant

with the method used. For that reason, the procedure was stopped after a few runs where a reasonable

number of variables where left. While all are not indicated as significant in the final run before the

procedure was aborted, all the variables left were indicated as significant in previous runs.

It also failed to indicate the significance of certain variables that have a large impact on the 28 d

strength. One example of this is Alite, which is the largest contributor to strength development during

the first 28 d as is discussed in previous chapters.

In the end the selected variables are similar to those used in the 1 d strength index, although Arcanite

being replaced with Aphthitalite. While both are present in small quantities they can have a negative

impact on the 28d strength and possibly a positive impact on 1d strength. For that reason the one

indicated by Unscrambler was used.

SO3 (XRF)

K2O

y = 0,1872x - 5,9968R² = 0,14

y = 0,1342x - 4,5059R² = 0,1169

y = 0,3529x - 11,076R² = 0,4297

-4

-3

-2

-1

0

1

2

3

27 29 31 33 35 37

Erro

r (M

Pa)

Measured strength (MPa)

SH 1d index

Error run 1

Error run 2

Error run 3

Linjär (Error run 1)

Linjär (Error run 2)

Linjär (Error run 3)

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Cl

d50

2 µm

15 µm

Alite Sum

Aluminate Sum

Aphthitalite

Belite_beta

Calcite

Fraction M1

Hemi-hydrate

In the end, as shown below, the index performed adequately.

Run 1 Run 2 Run 3

Correlation coefficient: 0.891 0.891 0.891

Number of samples in verification set: 27 27 27

Samples with error above 3 MPa: 2 0 0

Percentage of samples with error above 3 MPa: 7.41% 0% 0%

Table 4 - Results for produced index for SH 28 day compressive strength

Figure 23 - The difference between measured and predicted for 28d strength (without 1d as input) SH-cement from HTCs model

For 28 day the threshold for error is 3 MPa rather than 2 MPa and for all three runs the amount of

errors above this value was below 10 % as can be seen in Table 4. However, similarly to the 1 d, the

data set is small and for that reason the verification set is also smaller than desired.

Comparing this case to that of the 1 day index, Figure 23 indicates that bias is a larger issue in this

case. A random distribution of errors over the entire span is desirable to indicate low bias, and while

y = 0,4242x - 26,614R² = 0,3643

y = 0,3838x - 24,075R² = 0,6326

y = 0,4647x - 29,254R² = 0,5344

-4

-3

-2

-1

0

1

2

3

4

58,5 59,5 60,5 61,5 62,5 63,5 64,5 65,5 66,5

Erro

r (M

Pa)

Measured strength (MPa)

SH 28d index

Error run 1

Error run 2

Error run 3

Linjär (Error run 1)

Linjär (Error run 2)

Linjär (Error run 3)

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trendlines demonstrated an issue with bias for 1 d, the value describing the fit of the trendline to the

errors (R2) is higher in this case. This indicates a less random distribution and higher bias.

5.3.3 SH-Cement indexes discussion For SH-cement the increased importance of the PSD is apparent in the results. The final indexes show

good promise for prediction. Overall, 1d proved to provide better correlation than 28d as the impact of

unknowns will increase during the hydration. Using 1d strength as a parameter would increase the

precision of 28d indexes but reduces the overall usability of the model.

5.3.3.1 Parameter selection

As can be seen the variables used as input for the model varies from the variables identified by the

uncertainty analysis in Unscrambler. The results of the uncertainty analysis provides a good start

however, as mentioned, a theoretical understanding of the hydration reaction and the impacts of the

parameters must also be used.

In the case of 1d strength index for SH, the number of parameters needed to be reduced further from

the uncertainty analysis. In this case, the sum of Alite and Aluminate was chosen and the content of

the mineral forms where excluded. This is due to the fact that the total content of the minerals can be

assumed to have a higher impact compared to the form which they are present in.

The smaller data set also include some risks when the analysis is done in Unscrambler as random

occurrences can impact the parameter impacts. For example, if the Portlandite content happens to be

high for a sample with high strength this could mean that Portlandite is indicated as positively

impacting the strength. This is also one reasons for the need of having a theoretical understanding as a

background when selecting the parameters.

5.3.3.2 Including parameters from CR

While the focus as mentioned has been on the results from the process laboratory, 15 µm and 2 µm are

included from CR. SH-cement is a fine cement and the 32 µm size may not provide the necessary

variations for a robust model as it is typically around 90% with the deviations from this being

relatively small.

When including 15 µm, adding the 2 µm was also done. While this can be deduced from the 32-2 µm

and 32 µm parameter, having it separate reduced the number of parameters.

Adding this parameters was not taken lightly, as the PSD analysis at CR is not reported on all samples

in the data collection used. Comparing to the approximately 130 samples with data from the process

laboratory, only approx. 105 samples include the PSD analysis conducted at CR.

5.4 BAS-Cement As for SH-cement, runs in Unscrambler was used indicate statistical importance of a number of

variables. A full list of variables used and additional graphs are available in appendix. For BAS-

cement a larger data set is available compared to that for SH-cement. The indicated significant

variables are listed in Table 5.

1 d 28 d

SiO2 -0,2789 -0,274

Al2O3 -0,0771 -0,1817

CaO 0 0,1007

MgO 0,1847 0

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SO3 0,1727 0,7095

K2O 0,3204 0

Zn 0,1449 0

d50 -0,1799 -0,1461

Alite_M1 0,1339 0,3131

Alite_Sum 0,1029 0,144

Anhydrite -0,1147 0

Aphthitalite 0,3066 0

Arcanite 0,1753 0

Belite_beta -0,1732 0

Calcite -0,0689 0

CO2_XRD -0,0678 0

FA_Sum -0,0642 0

Fraction_M1 0,0979 0

Gypsum -0,4199 0

Hemi-

hydrate 0,4602 0,327

Lime 0,2442 0

Portlandite 0 -0,3229

Quartz 0,0833 0

Table 5 - Significant variables indicated by Unscrambler for BAS-cement

As shown in Table 5 a large number of variables was indicated as statistically significant for 1 d

strength and the number of variables had to be reduced to produce the index. It also did not indicate

aluminate as important while indicating aluminum as important. For 28 d a smaller number of

variables was identified, however, not all theoretically important variables was identified by

Unscrambler.

5.4.1 1d In the list below is the selected variables for the 1d index for BAS-cement.

SiO2

MgO

SO3

K2O

d50

Alite_sum

Alum_sum

Belite_beta

Calcite

FA_Sum

Fraction_M1

Gypsum

Hemi-hydrate

Several variables are removed for different reasons and Aluminate is added. In this case Anhydrite is

removed as a variable even though it is indicated as significant by Unscrambler and impact the setting

of the cement. However, the levels of Anhydrite over the period was typically 0% with few

exceptions.

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In terms of Aluminum, this is highly correlated to the content of flyash in the cement represented by

FA_sum.

The variables shown above yield the following results.

Run 1 Run 2 Run 3

Correlation coefficient: 0.928 0.928 0.928

Number of samples in verification set: 163 165 173

Samples with error above 2 MPa: 13 17 8

Percentage of samples with error above 2 MPa: 7.98% 10.30% 4.62%

Table 6 - Results for produced index for BAS 1 day compressive strength

Figure 24 - The difference between measured and predicted for 1d strength BAS-cement from HTCs model

In the case of BAS-cement a larger data set is available. However, the results shown in Table 6 shows

that one of the runs yielded results where over 10 % of the verification set differs from the measured

value. As shown in Figure 24, the bias is also greater in this run.

For BAS-cement, and particularly the 1 d strength, an unknown factor is the gypsum slurry from the

flue gas desulfurization scrubber in Slite. This is injected into the mills during BAS-grinding but not

during SH-grinding. The slurry solids contains mainly gypsum (CaSO4∙2H2O) but the quality of this

varies greatly. The impact of this will be discussed in section 5.4.3.1 Gypsum slurry5.4.3.1 Gypsum

slurry.

5.4.2 28 d SiO2

Al2O3

CaO

SO3

d50

Alite_sum

Fraction_M1

y = 0,2588x - 5,4841R² = 0,1211

y = 0,3378x - 7,3209R² = 0,233

y = 0,1921x - 4,1629R² = 0,0773

-5

-4

-3

-2

-1

0

1

2

3

4

5

17 18 19 20 21 22 23 24 25 26

Erro

r (M

Pa)

Measured strength (MPa)

BAS 1d index

Error run 1

Error run 2

Error run 3

Linjär (Error run 1)

Linjär (Error run 2)

Linjär (Error run 3)

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Hemi-hydrate

Portlandite

In the case of BAS-cement there are more significant differences between the variables used for 1 d

and 28 d. Unscrambler did not indicate that Aluminates was important in the case of both 1 d and 28 d

but is included in the 1 d index anyway as they have a significant impact on early strengths. However,

as the hydration of Aluminates is quick, the impact on the 28 d strength should be less significant.

In this case Portlandite is also added as a variable, this is indicated as significant by Unscrambler and

this is also supported by theory. Portlandite is an indication of prehydration of the cement and has a

significant negative impact on the cement strength.

Compared to 1 d, in this case CaO is added and MgO is removed. While MgO has an impact on the

cement properties through Periclase as well as stabilization of different Alite configurations, the

inclusion of Alite_Sum and Fraction_M1 will to some degree cover this. And as MgO is not indicated

as significant by Unscrambler for 28 d it can be removed.

While the Aluminates is not included, Al2O3 as well CaO is included. These, along with SiO2 will

correlate to the contents of both Aluminates and Flyash. As Unscrambler indicates these as significant

these are included instead of Aluminates and FA_sum.

Run 1 Run 2 Run 3

Correlation coefficient: 0.874 0.874 0.874

Number of samples in verification set: 166 164 180

Samples with error above 3 MPa: 11 11 8

Percentage of samples with error above 3 MPa: 6.27% 6.71% 4.44%

Table 7 - Results for produced index for BAS 28 day compressive strength

Figure 25 - The difference between measured and predicted for 28d strength BAS-cement from HTCs model

Table 7 indicates a slightly lower correlation coefficient than for other indexes, however still in at an

adequate level. And as the amount of verification samples with an error greater than the 3 MPa level

y = 0,4639x - 27,097R² = 0,3857

y = 0,3627x - 21,302R² = 0,2246

y = 0,3584x - 21,116R² = 0,1779

-6

-4

-2

0

2

4

6

53 55 57 59 61 63 65

Erro

r (M

Pa)

Measured strength (MPa)

Bas 28d index

Error run 1

Error run 2

Error run 3

Linjär (Error run 1)

Linjär (Error run 2)

Linjär (Error run 3)

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are below 10 % in all cases, the index can be said to perform adequately. Figure 25 in turn

demonstrates a slightly larger issue with bias in this instance compared to the 1 d index. However, the

errors are still sufficiently random (poor fit of the trendlines).

5.4.3 BAS-Cement index discussion In the case of BAS-cement additional unknowns are present compared to for SH-cement. SH-cement

is a “pure” product containing only clinker and small quantities of additives of known qualities, BAS-

cement on the other hand contains both fly-ash and gypsum slurry.

The amount of fly-ash can be estimated with the XRD-analysis however, the quality of the fly-ash in

the cement samples is not known. The fly-ash is shipped to Slite and stored in 2 silos in which

different qualities are mixed.

5.4.3.1 Gypsum slurry

A key unknown in the BAS-cement is the gypsum slurry, particularly for 1 d strength. The quality of

the slurry varies over time as it is a byproduct from the production of the clinker. Recently it has been

seen in Slite that slurry containing CaSO3∙½H2O can significantly delay setting time and impact the

short term strength.

BAS-cement has proven more difficult to accurately predict, this is possibly due to the fly-ash

addition. However, the results from the verifications of the indexes indicates that the majority of the

samples are within the boundaries (only around 7% above). Similarly to SH-cement the PLS models

created in Unscrambler has a significantly lower correlation coefficient compared to what is achieved

in the ANN model.

5.4.3.2 Parameter selection

Selecting parameters was done in the same way as the selection for the SH-cement. For the 28d

strength the number of identified parameters is very small.

As the data set is larger for BAS-cement, the parameter selection in Unscrambler should be more

robust. The risk of random occurrences giving erroneous results is reduced.

5.4.3.3 Fly-ash

The variations in fly-ash quality provides an unknown variable for the modelling. While the fly-ash is

tested as it arrives at the plant, the quality of the fly-ash used at any given time is not known and not

included in the data set for this project.

Further, the fly-ash used in the process varies in quality and fly-ash from some sources are coarser

than desired. As with clinker particles, coarser material will react slower and

5.5 Bias Reducing the bias has proven a key difficulty in this project. Although an important challenge, it has

not been possible to solve it during the course of this project.

5.5.1 Model parameter variations As mentioned, the model has built in functionality allowing to vary the model parameters. Using the

28 d index with the parameters presented in previous section, the model parameters was varied with

the aim of reducing bias without losing overall performance of the model.

The samples used for verification is not changed between the runs and the correlation coefficients

shown below are with the verification samples removed from the training set and the verification set

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computed. For that reason, the correlation coefficient shown in this section differs from the correlation

coefficient of the finished model, even with the default parameters used in the index.

As the verification set is not changed, the changes in correlation coefficients and graphs between runs

is for that reason only the impact of changes in model parameters.

To evaluate the bias, a “bias value” is calculated by multiplying the slope of the trendline with the R2

(fit) of the trendline. The setup of each case along with results are shown in Table 8. The graphs are

available in appendix x.

Case 1

(Reference)

Case 2 Case 3 Case 4

Model Parameters:

Kernel width (dimensionless) 0.1 0.1 0.1 0.25

Penalty for large weights/smoothening 0.000001 0.000001 0.000001 1E-09

Max. No. of data points per neuron 3 2 1 1

Correlation coefficients:

Training set 0.854 0.905 0.949 1

Verification set 0.675 0.563 0.468 0.213

Bias value: 0.1789 0.1172 0.0961 0.0185 Table 8 - Results from model parameter variations

Comparing the cases above, it is obvious that the bias reduces between with increasing number of

neurons. This means that the errors are significantly more randomly distributed over the entire range

compared to the reference case. However, looking at the correlation coefficient the issue of variance

can be seen to increase. In essence, the model is able to fully learn the training set and in Case 4

provides perfect correlation in the training set. The issue with this is seen in the verification set

correlation coefficients which demonstrates that while the model has learned the training set fully, it is

not able to apply this to predict unknowns.

In essence this means that the errors, while being more randomly distributed, are larger and in case 4

errors up to 20 MPa is recorded.

A near infinite number of possible combinations of the parameters are available, however, these cases

demonstrates the difficulty with decreasing the bias without losing overall performance. Overall, Case

1 provided the highest correlation coefficient for the verification set meaning that of these four cases,

this is the most capable configuration for prediction even though the bias is higher.

5.5.1.1 Automatic Optimization

The model features the functionality to optimize the model parameters automatically and these can

after this be saved for future use. This will balance the correlations of the training and the verification

set with the target to achieving highest possible correlation for both. However, this might not be

desired for this case as this can increase the bias of the model and trade-off the precision at the

endpoints of the interval for better overall precision.

This function for automatic optimization of the model parameters is also a slow process. While

possible within a reasonable amount of time for SH-cement where the number of data points is low,

the process is too for BAS-cement to be useful in this case. As mentioned, the possibility to store the

optimized parameters is available, however as the index will vary over time it will require updating

occasionally.

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5.5.2 Sample selection Sample selection was also tried in an effort to control the bias of the index. This was not possible for

SH-cement as the data set was small from the beginning, the histogram shown in Figure 26 also

indicate a less unbalanced distribution compared to that of BAS-cement.

Figure 26 - Histogram for 28d strength for SH-cement from Unscrambler

For the 1d prediction on BAS-cement, the variables identified as significant by the uncertainty

analysis are numerous and an index using these variables shows significantly worse bias compared to

the first 1d index for BAS. Using the same variables as is used in the first index yields a better result,

however this is still not any significant improvement over the original index.

5.52.1 Issues with sample selection

While Unscrambler provides a good way to select evenly distributed samples, it does not account for

all possible variations. The selected sample set must include the entire intervals for all variables used

in the final index, otherwise the model will extrapolate with potential for large errors.

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Figure 27 - Error plotted against measured strength for selected samples 28d BAS

Figure 27 shows an extreme example found during this project. In this case, the selected samples did

not include some samples with high SiO2 content. As the model found that a higher SiO2 content

meant a lower strength, in this case it extrapolated and approximated the strength to negative levels (-

31.53 MPa in the most extreme case). The small variations in SiO2 in the training set and the

correlations of these with lower strength meant that the model vastly overestimated the impact of SiO2.

To avoid similar situations, sample selections should be done carefully to ensure that the samples

selected represent the entire interval of the variables. It also means that predictions of samples where

one variable is outside the interval for which it is trained will not be accurate and must be controlled.

These samples should be added to the training set once the analyses are done, increasing the interval of

this/these variables and making accurate predictions possible in the future.

5.6 Clinker minerals To analyze and estimate the impacts of the clinker minerals on the strength, the scenarios function in

the ANN model was used. Only one parameter was allowed to vary at the time and the number of

levels where set to 25 in all cases. Creating scenarios with more than one parameter varying means, as

mentioned, that the model will create a scenario for every possible combination and the number of

scenarios will increase exponentially. For this reason, only one parameter was varied at the time.

5.6.1 Inconsistency Mathematical models using software such as these will always try to explain the output parameter

using the data given. For that reason, adding or removing parameters will change the impact of any

given variable.

y = -0,1421x + 10,423R² = 0,0014

-20,00

0,00

20,00

40,00

60,00

80,00

100,00

53 55 57 59 61 63 65

Erro

r (M

Pa)

Measured strength (MPa)

BAS 28d selected samples

Error

Linjär (Error)

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The samples also vary slightly between each run as the model automatically places samples in the

verification set which are randomly selected.

5.6.2 Results All figures demonstrating the impact of variation of the variables is available in Appendix A4 –

Clinker mineral correlations. In these figures it is seen that a higher Alite content correlates to a higher

strength both at 1 day and at 28 days. This is expected as hydration of Alite is responsible for the

majority of the strength development during this period.

The total Alite content measured is the sum of Alite in M1 and M3 forms. Fraction M1 as a parameter

indicates the share of Alite that is in the M1 form and it is a good parameter for the use in this case.

While the content of M1 is also reported, the amount of M1 will increase as the Alite levels increase

and this will obscure some impact of the various forms.

The results in this indicate the overall positive correlation for fraction of M1 for the 1 day strength.

However, the variation in strength depending on the M1 fraction is small. The fraction level varies

over an interval from roughly 36% to roughly 49% and the strength only varies by less than 1 MPa

over this interval. This parameter has also not been identified by the analysis in Unscrambler to be

significant.

Total Aluminate content is shown to be overall negative for the compressive strengths at both 1 day

and 28 days. However, interestingly a positive correlation between Cubic C3A content and

compressive strength is found at 1 day. However, again the impact is mild and the compressive

strength varies less than 1 MPa depending on the content of cubic C3A.

Regarding the alkali-sulfates these do not contribute to the compressive strength other than to similarly

to aluminates stimulate the setting of the cement. While mentioned in the guidance paper on clinker

reactivity that Langbeinite is preferred, Arcanite medium and Aphthitalite is undesired the correlations

found for 28-day strength would to some degree support this. The content levels of these are low

however and no conclusion can definitely be drawn from the correlations above.

5.6.3 Combinations An issue with this approach is that it fails to take effects of the combinations of the parameters into

account.

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Figure 28 - Alite_sum plotted against Belite_beta in Unscrambler

Example of this is the calcium-silicates Alite and Belite. As high Belite levels typically correlates with

lower Alite levels as indicated in Figure 28, the indicated negative impact of Belite may actually be

the negative impact of lower Alite content. The Belite will contribute to the compressive strengths,

although the main contributor for the first 28 days is the Alite, and for that reason the negative impact

of the Belite is indicated for these times.

Illustrating this issue was when setting time for BAS was studied in Unscrambler (not within this

project) and the Belite content was indicated as shortening the setting time. Belite is slow and should

not contribute to this, however free CaO will shorten the setting time, and as CaO + Belite forms Alite,

the increased Belite content also correlated to a higher free CaO content.

5.6.4 Fly-ash In Unscrambler, the fly-ash content is indicated to have a negative impact on 1d strength. This is to be

expected as the main fly-ash reactions will take place after this point. In the ANN model, the negative

impact is also seen, however, the scenarios and the results will vary depending on the data in the

model as well as which variables are selected. For that reason, several scenarios are used for fly-ash.

These figures are available in Appendix A4.3 Flyash.

For 28d, in Unscrambler the fly-ash content is indicated to be insignificant for the 28d strength model.

As seen when run in the HTC model, the correlation varies depending on the parameters used in the

model. The clear negative impact shown in Figure 61 possibly provides the best insight into the

impacts of the chemical content in the fly-ash as this model assumes a constant particle size of the

finished cement. The fly-ashes used are generally coarser than the ground clinker, gypsum and

limestone in the cement and as it is added after the grinding stage the fly-ash addition will impact the

overall PSD of the cement.

A negative impact of the fly-ash addition is to be expected as the fly-ash contains a variety of

compounds where only some are clearly reactive and form the desired C-S-H.

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The fly-ash is added to the cement after the cement mills and the fly-ash PSD will impact the PSD for

the final product. This needs to be considered and is seen in the scenarios from the indexes, including

or excluding the PSD variables will change the results of the scenarios and the indicated impact of the

fly-ash.

As mentioned, the quality of the fly-ash in each sample is also unknown, while the content of certain

minerals indicate the fly-ash content and can indicate the quality to some extent. However, the

majority of the fly-ash is amorphous and the individual chemical components of the amorphous part

cannot be analyzed through XRD. Regarding XRF analysis, as the fly-ash contains mainly silicon and

aluminum the variations and increases are to some degree masked by variations in the content of these

components in the clinker.

5.7 Difficulties Several obstacles where discovered during the process of this project. The number of samples

available for SH-cement from after May 2017 are fairly limited, limiting the potential for rectifying

actions of the bias. It also limits the interval over which the SH indexes operate.

5.7.1 Available data The amount of data available for each sample is large with many parameters being reported. A neural

network model can only be as good as the data though. Some key parameters are not added to the file

compiling all analyses for the samples, including the ferrite (C4AF) content. While this to some extent

is captured with the Fe2O3, adding this in the future would be beneficial as it impacts the strength and

the strength development of the cement.

As mentioned, the small data set for SH-cement also means that validation has been difficult and that

sample selection cannot be applied.

5.7.1.1 Measurement precisions

In this project, the XRD measurements form key parts of the data set. While XRD provide plenty of

valuable information the XRD results have several sources of error. Firstly, the Rietveld method is

based on PLS modelling and it normalizes the measured content to 100% meaning that while an

increase in Alite may mean a decrease in another mineral content. It can also mean that while the Alite

content is indicated as 70%, this does not account for an unmeasured minerals content.

5.7.2 Unknowns While the amount of data on the known and measured parameters are a key limitation, the unknown

parameters will also influence the performance of any model. As the cement production, subsequent

hydration and testing is complex procedures, there are several areas which can influence the actual

compressive strength and the measured compressive strength.

5.7.2.1 Fly-ash quality

Fly-ash varies plenty depending on the source, and today it is not kept track on which fly-ash is used at

which time. As the 28d strength for BAS-cement depends to some extent on the amount of fly-ash that

has reacted, this introduces an unknown making the prediction of 28d strength less reliable.

5.7.3 Neural Networks model functionality The latest version of the model stores the preference regarding number of samples used for training

set. This means that in the case that the user has its own specified verification set that can be used, the

model will still randomly select a verification set, reducing the number of samples used for training.

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In the case of using sample selection, the samples not marked for training could be used for

verification. These are roughly equally spaced over the interval and will not vary between runs making

them more ideal for this task than the randomly selected sample set that the model uses. A randomly

selected sample set may not be evenly distributed throughout the interval and for that reason this

method for verification may be less robust and indicate a model performance above or below the

actual performance.

The sample set used for verification will also vary between model runs and the GUI can only be

reopened by creating a new model. This means that in the case the user closes the GUI the verification

set and training set may vary compared to previous run. Adding or removing variables requires, by

definition, a new index to be created and this feature makes comparisons difficult.

5.7.4 Early and late strengths Prediction of the late strength proved more difficult and the correlation coefficients of the indexes

demonstrate this to some extent. For the early strength, a few parameters has a major impact on the

strength, mainly PSD and the accelerators as well as Alite content. The strength development during

this period is highly dependent on the amount of Alite that has been hydrated and the variables that

impact this therefore has a major impact.

A key difficulty in predictions are the unknown combination effects of the compounds as well as

content of unknown compounds.

5.8 Excel regression tool In addition to using Unscrambler and the Neural Networks model Excels built-in feature allowing

modelling was also tested. This tool is included with excel and is for that reason widely available, both

at the Slite plant but also other plants.

The following errors was found using the Excel based regression tool. However, these samples are

included in the model itself (included in the training set) and is therefore not an accurate reflection the

performance of the model for prediction. Given the lacking performance of the model demonstrated by

this graph and that the model will perform equal or worse for any unknown sample, the decision to not

further investigate this path is motivated.

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Figure 29 - Error vs measured strength from Excel

Coefficients Standard

error

t-quota p-value

Constant 24,37761 8,517882 2,861934 0,004327

SO3 2,369015 0,363368 6,519596 1,29E-10

H2O 0,634644 0,079615 7,971435 5,78E-15

SiO2 0,278519 0,144633 1,925693 0,054517

Al2O3 -0,89639 0,156434 -5,73015 1,45E-08

Fe2O3 -1,82537 0,474921 -3,84352 0,000131

CaO 0,026768 0,085681 0,312413 0,754813

Alite_Sum 0,202242 0,028771 7,029359 4,64E-12

Fraction_M1 0,035418 0,019427 1,823124 0,068679

Gypsum 1,484012 0,259115 5,727231 1,47E-08

Hemi-hydrate 1,456558 0,16978 8,579102 5,39E-17

Langbeinite 4,554151 1,018777 4,470216 9,01E-06

Lime -0,26386 0,116764 -2,25974 0,024121

Quartz 1,12334 0,301281 3,728543 0,000207

R_wp -0,43184 0,117267 -3,68256 0,000247

K2O -3,76614 1,1574 -3,25396 0,001189

Table 9 - Results from Excel regression analysis

The excel tool is a very basic tool, allowing only the use of a limited number of variables for

prediction of a y-variable. Identifying insignificant variables are also significantly more difficult and

requires interpreting the results.

Seen in Figure 29 and Table 9 is the results from the Excel tool. In this case, interpreting the results

led to R_wp, Langbeinite and H2O was identified as significant variables. R_wp is simply a residual

from the Rietveld method, Langbeinite content may impact the 28-day strength however many of the

samples in the data set has a Langbeinite content of 0 % with a maximum of 0.55%. H2O is a measure

of the water demand when doing the setting time analysis, this varies depending on the content of

y = 0,5718x - 33,31R² = 0,5718

-8

-6

-4

-2

0

2

4

6

8

51 53 55 57 59 61 63 65

Erro

r (M

Pa)

Measured strength (MPa)

Excel regression BAS 28d

Error

Linjär (Error)

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several important minerals meaning that it may be interesting to include. However, it varies little

between samples and as the minerals that impact H2O needed impacts the strength in different ways, it

is better to include this separately.

Overall, the Excel tool provides a linear model with comparatively high bias. As the samples used for

verification is the same as is used for training the model, the correlation between the models prediction

and measured values are similar to what in the ANN model is the correlation coefficient for the

training set. However, as this method showed little promise and the development of the index was

significantly more complicated than using Unscrambler followed by the ANN model, this method was

abandoned.

As is seen in the study on the clinker minerals, the impact of these on 28 day strength is not linear. It

varies depending on the content of the specific mineral. Several of the compounds found in cement are

not either good or bad, but rather have an optimum which linear models fail to account for in a

sufficient way.

However, for a user with experience and detailed knowledge in the theory of cement hydration the

Excel tool can be used to provide estimations and crude predictions of compressive strengths. If this is

desired, the user should first limit the number of variables by selecting the theoretically most

important variables. The number of variables should be below the number that the Excel tool can

handle to speed up the process.

5.9 Sustainability Looking at the sustainability aspect of production of the cement, replacing more clinker with fly-ash

and optimizing the PSD is identified as potential uses. However, while the index will allow for

optimization of these variables with regards to the final quality, further problems may arise.

5.9.1 Fly-ash As mentioned, the impact of flyash content has been studied demonstrating a generally negative

impact on the cements 1 day compressive strength. This is to be expected as the pozzolanic reactions

will take place after this point. For 28 day strength the impact is not indicated as significant. The

approach for increasing the fly-ash addition would, based on these results, mean increasing content of

the compounds that benefit the 1 d strength. However, looking at Aluminates as an example of this,

this negatively impact the 28 day strength meaning that to maintain the same 1 day strength with

increasing fly-ash addition by increasing Aluminate content will overall impact the 28 day strength

negatively.

As mentioned in previous parts of this report, flyash is also a byproduct of coal firing power plants and

as the number of these plants decrease in favor of more sustainable alternatives, the flyash supply will

also decrease and the cost of this may rise.

5.9.2 PSD Particle size and strength is clearly correlated as shown above and a finer cement will, to an extent,

increase both the early and late strengths of the cement. However, optimizing the grinding stage to

achieve approved cement qualities without unnecessary grinding can be an interesting use for the

indexes.

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5.10 Tool development During the course of the project, tools have been developed to assist in the work. These are mainly

simple programs written in Visual Basic for Applications (VBA) and used as macros in excel. The

tools are to some extent specific for the combination of software’s used in this project (Unscrambler,

Excel and the HTC model) but have the possibility to be used for a wider range of applications.

5.10.1 Extraction tool for sample selection While Unscrambler can assist with marking evenly distributed samples over the interval, it lacks the

functionality to extract the complete samples selected only providing the sample numbers and

approximated and measured Y for these samples. For that reason, a macro for these selections where

developed.

To use this macro, the sample-id’s which should be extracted is pasted into the first sheet and the

complete data set into another sheet. When run, the program goes from top to bottom in the list of

sample-id’s and looks for these samples in the data set, copying and pasting the selected samples into a

third sheet. Two versions of this macro was created, one where it copies and pastes leaving the

original data set complete (including the extracted samples) and one where the macro deletes the row

after copying it to create two data sets. Creating the two data sets allows for using one for training and

one for verification, in this case it also creates a new sheet and pastes the original data set into this.

The full VBA-code for these macros are presented in Appendix A5 – Sample selection VBA and A6 –

IP21 fetch.

5.10.2 “IP21-fetch” Results from analyses of samples from the production process at the process laboratory is available in

the process monitoring system used at the plant: Aspen InfoPlus21 or IP21 for short. This software has

an add-on for Excel allowing for gathering of both historic and current data into an Excel-file.

However, this add-on has historically proven to interfere with the HTC model software.

To be able to use the indexes for prediction of strengths for process samples, a tool is needed to be

able to gather, format and insert the process data into the model. While the add-on can achieve this by

simply using the add-on in the model file, this will be both time consuming as well as work intensive

for the user.

Using the add-on to gather the results of analyses conducted on samples from the cement mills at a

time specified by the user the macro performs several checks and tasks in the background. When

initiating the macro, the user is also required to specify the current model for the selected cement

types, as this can shift over time. After this, the macro runs completely in the background.

Firstly, as the values for the parameters at a specific time is always the results from the latest samples

and samples are only collected from running mills, the macro checks the status of the mill at the

specified time. This is to avoid cases where one mill may have been stationary for weeks for repairs

and where the values therefore are old. However, the macro can also be run without the condition of

the mill being online.

After this, the macro checks the type of product being produced by looking at which silo the product is

transported to after milling. The macro then transfer the sample results at the specified time into the

selected version of the index and strength can be predicted for this.

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5.10.3 Tool development discussion While not part of the main objective, to enhance the usefulness of the finished indexes and to simplify

future work in this area at the plant the additional tools where developed.

5.10.3.1 Sample selection and sorting

As mentioned, Unscrambler does not sort out the entire samples when equally spaced samples are

marked. For that reason the macros where developed. While useful in this project, it can also be useful

as a simple way to sort out a list of samples using the sample-id:s or other variables. As this has been

developed as a part of this project fully within the Excel VBA interface, the macros are both “free”

and can be readily made available to anyone within the group without need for additional software.

These macros are not unique and other methods and add-ons to Excel can to some extent provide the

same functionality. However, the built-in functions in Excel is less flexible and the use of these are

time consuming and are less user-friendly. Also, installing add-ons or additional software to

computers owned by HeidelbergCement Group to fulfil the need requires the approval and assistance

of the IT department to guarantee that no harmful software enters the group’s networks.

The code for these macros are found in Appendix and while not elegant, it fulfils the tasks.

5.10.3.2 “IP21-fetch”

The Excel-add-on for the Process monitoring tool (“IP21”) provides the possibility to get historic and

current values for a variety of different process parameters. Interesting in this project is the data from

the process laboratory where the analysis results for every sample from the production process is

available through the process monitoring tool.

However, issues regarding having the IP21 add-on installed while running the ANN model have been

found at the plant previously. For that reason the work of creating a tool which can easily transfer

values at a specified time was initiated. While possible to manually, this tool reduces the risk of user

error as well as speeds up the process by formatting and checking the cement types etc. before

transferring the data.

Currently, the program is limited to having a single index for each of the cement types SH and BAS

and it requires the format in the index to match the format used in the file. However, as this format

matches to some extent the order of variables used in the shipping file, any changes will be minor.

Option of having several indexes for each cement type can also be added with ease using the code

already available.

The tool itself is described in the results chapter of this report and the code is available in Appendix.

The function IsFileOpen is available on Microsoft support: (https://support.microsoft.com/en-

us/help/291295/macro-code-to-check-whether-a-file-is-already-open).

6. Conclusions/Recommendations The indexes produced in this project has shown encouraging results on the abilities for predictions of

the cement strength. In addition to this, the procedure used in this project can simplify the generation

of new indexes for other cement types or other properties in the process.

6.1 Indexes The indexes have proven to be able to predict the compressive strength with relatively low error,

however consistent work on updating these must be done to both maintain and improve the current

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performance. The indexes can also be used for scenario evaluations as seen regarding fly-ash, however

this is highly sensitive to changes in the index.

6.1.1 Sustainability The indexes themselves can be used in several ways beyond the strength predictions. While a

consistent high quality of the cement is always the target, this needs to be balanced against the

production costs and sustainability.

A clear example of application where the indexes could benefit the work towards sustainability is

regarding the particle sizes. While a smaller particle size of the cement will increase the strengths

(within boundaries), the electrical energy demand for the grinding step is big cost for the company.

Particle sizes are to some extent regulated in the agreements and standards, but optimizing the

grinding step to meet these regulations and the quality demands without unnecessary grinding can

possibly provide savings for the company.

Similarly, using indexes like these to provide additional insight into the impacts of various variables

regarding the clinker burning stage as well as the raw meal grinding can help optimize these areas. The

thermal energy demand for the kiln is responsible for the vast majority of the total energy demand of

the plant. This would however, demand additional work with adapting an index to this and it requires

additional testing to be done.

It should be noted that while the indexes can provide prediction they cannot replace testing.

6.1.1.1 Procedure

While the indexes can be used directly to optimize the cement milling step, using the procedure used

in this project may provide more benefits elsewhere in the cement production process. Producing

ANN-indexes for prediction of other process parameters may aid in overall process optimization.

6.1.2 Setting time Prediction of setting time was mentioned in the project description to be done with regards to available

time. However, there are some key issues with prediction of this. The setting time data set is not fluent

over the entire interval and it also has a large variance, making predictions difficult as neither PLS or

the ANN model is designed to cope with this.

6.1.3 Different strengths Predicting 1d strength proved easier for both cement types when compared to 28d strength. This may

be due to the unknowns having increasing impact on this strength. Using early strength in the

prediction of 28d strength would improve the accuracy and performance of the model, however as

these are not available at the same time as the process laboratory results this has not been included in

this project.

Including early strengths should not be done by simply adding these to the indexes described in this

project, rather, the procedure of analysis in Unscrambler followed by insertion in the ANN model

should be repeated. The reason for this is that the early strength will depend highly on certain variables

which for that reason already will be included in the model. Typically, including the early strengths

would mean a decrease in the number of other variables which needs to be included.

6.1.4 Non-linearity of index Linear models are not ideal for use in this type of scenarios, as the impact of chemical composition

will vary depending on the levels of the compounds. Example of this is the content of Aluminates on

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the 1d compressive strength. While Aluminates stimulate the setting and the strength development, it

does not directly contribute to the compressive strength.

6.2 Bias Work on reducing the index bias needs to be continued. As the data set grows in size, new attempts at

sample selection can be made, however as seen this needs to be done carefully including all extreme

samples as well as a lare number of possible combinations.

Mentioned by Dr. Skocek at Heidelberg Technology Center, the creator of the model, is the wish to

have 2n samples, where n is the number of variables used in the index. For 10 variables, this means

1024 samples, and decreasing the number of variables used to a level significantly below 10 may also

have a significant impact on the prediction capabilities. For these reasons, parameter selection is a

balancing act between overall performance, bias and robustness.

Not including parameters that are significant according to theory but not indicated as significant for

the current data set may lead to a reduced performance over time.

6.3 Recommendations Some issues/weaknesses has been discovered during this project, and the following recommendations

will benefit future work in these matters. They may also benefit other projects and the daily operations

at the plant.

6.3.1 Additional particle sizes reported To better represent the variation in the PSD of finer cement types like SH-cement, additional sizes

should be added to the reports from the laser diffraction at the process laboratory. Typically, SH-

cement have a very low fraction of the cement larger than 32 µm and sizes such as 15 µm may better

represent the variations in the PSD of these fine cements.

Cementa is currently in the process of purchasing new laser diffraction equipment for both laboratories

which provides an opportunity for evaluation of which sizes should be reported from the process

laboratory.

6.3.2 Analysis result compiling There are several issues surrounding the way that analysis results for shipping samples are available

today. The Excel file containing this data has been a key asset in this work and this file is a valuable

asset to any project or investigation where this data is needed. Today however, this file is updated by

hand with data from multiple sources.

Gathering and inputting data by hand have several drawbacks: It is time consuming and involves the

risk of human error like spelling mistakes etc. Adding to this is the fact that CR and the process

laboratory does not store the analysis results in the same database and that samples from the same

shipment have different sample-id:s in the different databases. This makes checking possible errors

difficult and time consuming.

Several improvements therefore should be made in this area, including synchronizing the sample-id:s.

However an automated system for compiling results of all analyses for each shipment into a usable

format (for example an Excel file) should be prioritized.

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6.3.3 Increased control of fly-ash There are large variations in the quality of the fly-ash depending on the source and over time. And

while all fly-ash are compliant with the quality requirements set by the plant, issues can still occur. An

example of this is the particle sizes of the fly-ash.

The current analyses on the fly-ash also lack analyses on the reactivity of the fly-ash, while the

chemical composition analysis through XRF and ICP may indicate this.

6.3.3.1 Storage

The plant has two silos for storing the fly-ash upon arrival to the plant which provides opportunities

for further control of the quality of fly-ash used in the production. Knowing the quality of the fly-ash

used can assist in determining the amount that can be added as well as identify sources for cement

quality issues.

6.3.4 XRD, Clinker reactivity and Indexes Cementa in collaboration with other companies within the group currently works on both XRD and

Clinker Reactivity with the aim to learn more and develop current methods. The progression of this

work is highly interesting to the future development of the indexes as these form a substantial part of

the index performances.

For that reason, it is suggested that the users of the indexes are involved in this work or is briefed

continuously on the progress of this.

7. Further work An obvious further work is the continued work on the results of this project. A model should be alive

and requires continuous updating and work to remain accurate for a longer period of time.

The tools used in this project is purely mathematical and not specifically adapted to the compressive

strengths in any way. As the procedure used where Unscrambler was used in combination with the

neural networks model has proven beneficial, this method can be applied to other subjects.

Increasing the ecological and financial sustainability of the cement production is a main focus for

Cementa and for that reason an investigation regarding application of the model for process

optimization regarding alternative fuels and raw materials should be conducted.

7.1 Indexes Indexes must be updated continuously and section 7.1.1 Index maintenance. The theoretical

knowledge as well as the procedure found during this project and presented in this report may also aid

in creation of new indexes for other cement types. This becomes increasingly important as new cement

types is invented to lower the ecological impact of the production of cement with potentially increased

variations in the cement.

7.1.1 Index maintenance As mentioned, the indexes must be kept alive and updated continuously. For that, the quality

department in Slite will need to not only use the index but also evaluate the results. The index predicts

using the data it is trained with, and if the training data is not comparable to the samples being

predicted the index will not be accurate.

With this in mind, a clear warning should be added to Excel when the samples being predicted have

one or several variables outside the trained range.

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Checking the verification set of the index should also be done regularly depending on how often the

index is used. If the share of samples in the verification set that exceeds the defined error margin

exceeds 10 %, a new evaluation of the input data should be conducted to find potential changes in any

variable, both included and excluded in the model. The potential impact of these variables on the

cement strength can then be investigated in the current index after and if theory supports it, it can be

added or removed.

If this fails to enhance the performance of the index, the full procedure including runs in Unscrambler

should be conducted with the current data set to improve the index. Runs in Unscrambler should be

done regularly on the current data sets as these grows continuously, however, the frequency of these

runs depends on the number of samples and process variations meaning that this will be at the users

discretion.

7.1.2 Other uses of the model A vast number of things in the plant can also be predicted using indexes similar to this and using the

procedure presented in this project will help with the creation of these. This requires theoretical studies

of the topic however, as correlation does not necessarily mean causality. It also requires good ways of

extracting data from current databases, something that is already available for the process data stored

through IP21.

7.2 Sustainability The cement industry have massive challenges ahead with regards to sustainability. Both from a

financial and ecological standpoint, innovation must be prioritized. From a financial standpoint the

increasing cement production in developing countries means that the cement price and quality must

remain competitive.

Discussed during this project is also the fact that ecological sustainability and financial sustainability

will increasingly be connected. Today, carbon emission rights are a clear example of this, but this will

increase with increasingly strict regulation on the subject. This motivates large focus on research and

development of the process, and the tools used in this project may simplify this work as

approximations may be done before trials are conducted.

As the fly-ash is a result of coal burning in industries and power plants, fly-ash supply will decline

during coming years. Introducing a cost variable as well as an ecological impact variable in these tools

may help to optimize the fly-ash addition while maintaining proper quality.

7.3 Process optimization The plant in question logs plenty of process parameters continuously and using similar methodology to

that of this project, indexes can be developed for several areas. This will allow for possibility to search

for causes of errors as well as optimizing the process in itself.

There are plenty of limiting factors regarding product quality, cost and emissions and connecting these

and finding not only single, but multiple parameters, that can be changed to improve these areas will

benefit Cementa. However, for this, a larger project is required or several smaller projects working on

different areas.

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References

[1] Å. Truedsson, Cementprocessen, Slite: Cementa Research, 2004.

[2] W. Kurdowski, Cement and Concrete Chemistry, Kraków: Springer, 2014.

[3] Techincal Commitee CEN/TC 51 "Cement and building limes", Cement - Part 1: Composition, specifications and conformity criteria for common cements, 2011.

[4] J. Aguirre Castillo, Cementtillverkning, Slite: Cementa AB, 2018.

[5] HeidelbergCement Group, Application of XRD/Rietveld Analysis for Production Control, 1 ed., 2016.

[6] T. Hjellström, Interviewee, Continuous discussions during the project regarding the process.

[Interview]. 2019.

[7] Netzsch, "Simultaneous Thermal Analysis," [Online]. Available: https://www.netzsch-thermal-analysis.com/en/commercial-testing/methods/simultaneous-thermal-analysis-sta/. [Accessed 29 May 2019].

[8] H. F. W. Taylor, Cement Chemistry, 2nd ed., London: Thomas Telford, 1997.

[9] The Guardian, "The Ultimate Climate Change FAQ: Which industries and activities emit the most carbon?," The Guardian, 28 April 2011. [Online]. Available: https://www.theguardian.com/environment/2011/apr/28/industries-sectors-carbon-emissions. [Accessed 14 April 2019].

[10] S. Hamnqvist, "De släpper ut mest koldioxid i Sverige," Sveriges Natur, 18 May 2017. [Online]. Available: http://www.sverigesnatur.org/aktuellt/de-slapper-ut-mest-koldioxid-sverige/. [Accessed 14 April 2019].

[11] K. Larsson, "Prediction of compressive strength 28 d - Excel model," Cementa, 2013.

[12] E. Marsicano, "Guidance Paper: Clinker Reactivity," Heidelberg Technology Center, 2014.

[13] P. C. Hewlett, Lea's Chemistry of Cement and Concrete, Oxford: Elsevier, 1998.

[14] K. Larsson, Cementkemi - Grundkurs presentation, Slite: Cementa Research, 2008.

[15] M. J. Y. H. S. N. &. C. L. McCarthy, "Evaluation of Fly Ash Reactivity Potential Using a Lime Consumption Test," Magazine of Concrete Research, vol. 69, no. 18, pp. 954-965, 2017.

[16] S. Wold, M. Sjöström and L. Eriksson, "PLS-regression: a basic tool for chemometrics," Chemometrics and Intelligent Laboratory Systems, no. 58, pp. 109-130, 2001.

[17] Camo Software AS, The Unscrambler Methods, 2006.

[18] D. J. Skocek, "Cement Strength Predictions using Neural Networks," Heidelberg Technology Center, 2018.

[19] S. Singh, "towardsdatascience.com," Towards Data Science, 21 May 2018. [Online]. Available: https://towardsdatascience.com/understanding-the-bias-variance-tradeoff-165e6942b229. [Accessed 29 July 2019].

[20] B. MacNamee, P. Cunningham, S. Byrne and O. I. Corrigan, "The problem of bias in training data in regression problems in medical decision support," Artificial Intelligence in Medicine, vol. 24, no. 1, pp. 51-70, 2002.

[21] A. Bourtsalas, J. Zhang, M.J.Castaldi and N.J.Themelis, "Use of non-recycled plastics and paper as alternative fuel in cement production," Journal of Cleaner Production, vol. 181, pp. 8-16, 2018.

[22] F. Pacheco-Torgal, S. Miraldo, J. A. Labrincha and J. D. Brito, "An eco-efficient approach to concrete carbonation," in Eco-efficient concrete, Woodhead Publishing, 2013, pp. 368-385.

[23] K.-L. Du and M. Swarmy, Neural Networks and Statistical Learning, London: Springer-Verlag, 2014.

[24] D. J. Skocek, "Neural Networks model: User Manual," Heidelberg Technology Center, Leimen, 2019.

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Appendices

A1 - Partial Least Square Regression Partial Least Square regression was introduced by Herman Wold in 1975 and provided a new

approach to multivariate modelling.

The data set used for the modelling is divided into two matrices X and Y. X contains the input

variables and Y contains the known values for the output variables. Different parameters are typically

stored as different columns in the matrices and different samples are stored in different rows. The

process of making the PLS model is then dependent on the algorithm used, however in this project

NIPALS (Non-linear Iterative Partial Least Squares) has been used.

A1.1 NIPALS algorithm NIPALS algorithm is iterative and is run in component. One component is run until the model

converges, after this, the data from this component is removed from the X and Y and the next

component will restart the process with the new X and Y.

The NIPALS algorithm works by first finding a starting vector u (Y-scores) which is one of the Y

columns, after this the X weights are calculated [16]:

𝑤 = 𝑋′𝑢/𝑢′𝑢

When weights have been found, the X-scores are calculated:

𝑡 = 𝑋𝑤

Y-weights are calculated:

𝑐 = 𝑌′𝑡/𝑡′𝑡

And after this, the Y-scores u are updated:

𝑢 = 𝑌′𝑐/𝑐′𝑐

When this is done, the algorithm checks the convergence by checking

‖𝑡𝑜𝑙𝑑 − 𝑡𝑛𝑒𝑤‖

‖𝑡𝑜𝑙𝑑‖< 𝜀

Where ε is small (<10-6). If not fulfilled, new X-weights are calculated using the new u value. If

fulfilled the model removes the current component data from X and Y and continues with the next

component:

𝑝 = 𝑋′𝑡/𝑡′𝑡

𝑋 = 𝑋 − 𝑡𝑝′

𝑌 = 𝑌 − 𝑡𝑐′

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The p and c variables are called the X and Y-loadings and contains one value for each input parameter

for each component. The X-loadings when plotted with the Y-loadings show the impacts of each of

the parameters in the selected component. [16]

Figure 30 - X- and Y-loadings for 1d model for SH-cement

Figure 30 shows the first 2 components and the different parameter contributions. The X-axis show the

parameter impacts in the first component and Y-axis shows the impacts in the second component.

Further from 0 demonstrates a higher impact and an example from the graph above is 15 µm which

will positively correlate with 1d in both components while d50 will correlate negatively in both

components.

Figure 31 – The number of components impact on the degree of explained Y-variance

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The explained variance will increase with the number of components until no more useful information

can be found in the X-data. However, the majority of the explained variance will be from the first few

components, and beyond these the risk of noise influencing the model increases.

A2 – Neural Networks Different Neural Network algorithms are available in the model, however, the RBFN is used for all

indexes as this is the most developed algorithm in the current version.

A2.1 Radial Basis Function Network Radial Basis Function Network (RBFN) is the model most used in this project. RBFN models take the

following form:

�̅�(𝑋) = ∑ 𝑤𝑖ℎ(𝑥𝑖)

The w is the weight and h(x) is the radial basis function. Together these form the neuron, and the

calculated value for the model is the sum of impacts from all neurons. The radial basis function will

vary depending on the distance of the point from the neural center. RBFNs typically only has one

hidden layer. [23]

RBFN learning is a 2 step procedure where the first step is placement of the neural centers and the

second step is learning the weights. Several methods for placement of the neural centers can be used,

which one is used in this project is not known as the model code is protected. The weight learning can

also be done using several methods, however when the neural centers are known this is reduced to a

linear optimization problem and a Least-squares approach is often used. Specifics on the weight

learning is also now known for the same reason as for the neural centers. [23]

Several functions can be used as the radial basis functions, however in the model used in this project

the Gaussian function is used.

ℎ𝑖(𝑥) = exp (−𝑟2

2𝜎2)

In this radial basis function r denotes the distance between the data point and the neural center and σ

denotes the kernel width of the neuron.

The algorithms of the RBFN shows that the neurons closer to the data point will contribute more to the

prediction.

Model parameters can be changed in the model, these are “Max. number of data points per Neuron

>1”, “Penalty for large weights” and “Dimensionless kernel width”.

Dimensionless kernel width in this model does not change the kernel width directly but varies the

automated algorithm that optimizes the kernel width. Kernel width needs to be adapted to the data set,

which the algorithm does and needs to vary for the data set as points are unevenly spaced over the

interval. Typically, the distance between points and the variations in the data set determine the optimal

kernel width. The algorithm used cannot be described further as the code is protected by the creator.

[24]

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The maximum number of data points per neuron parameter allows the user to influence the number of

neurons used. A higher number of neurons will give a larger variance and smaller bias of the model,

and 3 is set as default value in this model. [24]

Penalty for large weights are local smoothening of the model, a higher penalty will reduce the

influence of high neural weights on the model. [24]

A3 – Unscrambler results for Bas and SH

A3.1 SH-cement Prediction of compressive strengths using the PLS method in Unscrambler with uncertainty analysis

identifies the following weighted coefficients (B_0 is the β coefficient as shown in Equation 1):

1 d 28 d

B_0 -4,0997 26,0514

SiO2 0,0000 0,0000

Al2O3 0,0000 0,0000

Fe2O3 0,0000 0,0000

CaO 0,0000 0,0000

MgO 0,0000 0,0000

SO3_XRF 0,2830 0,7105

K2O 0,1793 -0,3245

Na2O 0,0000 0,0000

Cl 0,2450 0,3676

ZnO 0,0000 0,0000

32 my 0,0000 0,0000

32-2 my 0,0000 0,0000

d50 -0,3192 0,0000

2 µm 0,2030 0,0000

3 µm 0,2087 0,0000

15 µm 0,3888 0,4786

Alite_CS 0,0000 0,0000

Alite_M1 0,0000 0,0000

Alite_M3 0,2213 0,0000

Alite_Sum 0,2327 0,0000

Alum_cubic -0,1916 -0,1166

Alum_ortho 0,0000 0,0000

Alum_Sum -0,2038 -0,1588

Anhydrite 0,0000 0,0000

Aphthitalite 0,0000 -0,2983

Arcanite 0,1523 0,0000

Belite_beta -0,2043 0,0000

Calcite -0,1655 -0,0754

CO2_XRD -0,1664 -0,0742

fCaO XRD 0,0000 0,0000

Fraction_M1 0,0000 0,0000

Gypsum 0,0000 0,0000

Hemi-

hydrate

0,1314 0,0000

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Langbeinite 0,0000 0,0000

Lime 0,0000 0,0000

Periclase 0,0000 0,0000

Portlandite 0,0000 0,0000

Quartz 0,0000 0,0000

R_wp 0,0000 0,0000

Table 10 - Weighted coefficients for SH-cement from Unscrambler

The parameters identified as unimportant is down weighted between and in the table above have

coefficient of 0. For 28d strength, only 5 parameters are identified as important in the last PLS run and

therefore the important variables from the previous run is used.

Figure 32 & Figure 34 graphically represents the data shown in Table 10.

Figure 32 - Weighted coefficients for significant variables from Unscrambler for 1d SH

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Figure 33 - PLS model performance for 28d for SH-cement from Unscrambler

Figure 34 - Weighted coefficients for SH 28d strength from Unscrambler (blue marked as insignificant)

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Figure 35 - PLS model performance for 28d for SH-cement from Unscrambler

A3.2 BAS-cement Unlike the analysis for SH-cement, for BAS-cement the runs in Unscrambler is limited to the analyses

from the process laboratory but including the strengths (which are measured at CR). The reason for

this is the limited number of analyses run on BAS-cement at CR and that certain analyses has been

phased out as it was considered to have lower importance at this time. Below is the identified weighted

coefficients (B_0 is the β coefficient as shown in Equation 1):

28 d 1 d

B_0 39,4747 15,4737

SiO2 -0,2740 -0,2789

Al2O3 -0,1817 -0,0771

Fe2O3 0,0000 0,0000

CaO 0,1007 0,0000

MgO 0,0000 0,1847

SO3 0,7095 0,1727

K2O 0,0000 0,3204

Na2O 0,0000 0,0000

Cl 0,0000 0,0000

Zn 0,0000 0,1449

32 µm 0,0000 0,0000

32-2 my 0,0000 0,0000

d50 -0,1461 -0,1799

Alite_CS 0,0000 0,0000

Alite_M1 0,3131 0,1339

Alite_M3 0,0000 0,0000

Alite_Sum 0,1440 0,1029

Alum_cubic 0,0000 0,0000

Alum_ortho 0,0000 0,0000

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Alum_Sum 0,0000 0,0000

Anhydrite 0,0000 -0,1147

Aphthitalite 0,0000 0,3066

Arcanite 0,0000 0,1753

Belite_beta 0,0000 -0,1732

Calcite 0,0000 -0,0689

CO2_XRD 0,0000 -0,0678

fCaO XRD 0,0000 0,0000

FA_Sum 0,0000 -0,0642

Fraction_M1 0,0000 0,0979

Gypsum 0,0000 -0,4199

Hemi-

hydrate

0,3270 0,4602

Langbeinite 0,0000 0,0000

Lime 0,0000 0,2442

Periclase 0,0000 0,0000

Portlandite -0,3229 0,0000

Quartz 0,0000 0,0833

R_wp 0,0000 -0,0838

Table 11 - Weighted coefficients for BAS-cement from Unscrambler

As with SH the identified significant variables are used as a starting point, however, the HTC model

varies from the PLS regression in Unscrambler. For this reason, as well as that some variables are

connected or dependent on other, the selection of variables are changed to some extent in the final

models.

Figure 36 - Weighted coefficients for significant variables from Unscrambler for 1d BAS

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Figure 37 - PLS model performance for 1d strength BAS from Unscrambler

Figure 38 - Weighted coefficients for significant variables from Unscrambler for 28d BAS

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Figure 39 - PLS model performance for 1d strength BAS from Unscrambler

A3.3 Anläggningscement

Figure 40 - PLS model performance from Unscrambler for Anläggningscement

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Figure 41 - Weighted coefficient (only significant) from Unscrambler

A4 – Clinker mineral correlations The indexes for 1d and 28d prediction for SH-cement is used as foundation and the additional clinker

minerals are added to evaluate the correlation of the variations in strength compared to the level of

these minerals. To identify the impact of clinker minerals on the strength, the scenarios tools in the

model is used. Fixing all other parameters at the average level, only clinker minerals are investigated.

A4.1 Scenarios 28d SH Following are scenarios where the variables are allowed to vary between the highest and lowest value

in the training set at 25 levels. Other variables are set to their mean value.

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A4.1.1 Alite

Figure 42 - 28d strength as variation in Alite content

Figure 43 - 28d strength as variation in fraction of M1 Alite to Alite sum

y = 0,0064x2 - 0,6398x + 76,77R² = 1

60,5

61

61,5

62

62,5

63

63,5

64

56 58 60 62 64 66 68 70 72 74

28

d S

tren

gth

(M

Pa)

Alite Sum (%)

28d strength - Alite sum

28d strength

Poly. (28d strength)

y = 0,0011x3 - 0,1449x2 + 6,065x - 21,172R² = 1

61,8

61,9

62

62,1

62,2

62,3

62,4

62,5

62,6

36 38 40 42 44 46 48 50

28

d s

tren

gth

(M

Pa)

Fraction M1 (%)

28d strength - Fraction M1

28d strength

Poly. (28d strength)

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A4.1.2 Belite

Figure 44 - 28d strength depending on Belite content

A4.1.3 Aluminate

Figure 45 - 28d strength depending on variation in Aluminate content

y = 0,0063x2 - 0,1527x + 63,148R² = 0,9973

62,1

62,2

62,3

62,4

62,5

62,6

62,7

62,8

0 5 10 15 20

28

d S

tren

gth

(%

)

Belite content (%)

28d strength - Belite

28d strength

Poly. (28d strength)

y = 0,0917x2 - 1,5241x + 68,271R² = 0,9994

61,8

62

62,2

62,4

62,6

62,8

63

63,2

63,4

63,6

4 5 6 7 8 9

28

d S

tren

gth

(M

Pa)

Aluminate Sum (%)

28d Strength - Aluminate sum

28d Strength

Poly. (28d Strength)

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Figure 46 - 28d strength depending on cubic C3A

Figure 47 - 28d strength depending on variations in orthorhombic C3A content

y = 0,0436x2 - 0,6424x + 63,922R² = 0,9998

61

61,5

62

62,5

63

63,5

64

0 1 2 3 4 5 6 7 8

28

d s

tren

gth

Cubic C3A (%)

28d strength - Cubic C3A

28d strength

Poly. (28d strength)

y = -0,0233x3 + 0,1793x2 - 0,4954x + 62,239R² = 0,9979

61,7

61,75

61,8

61,85

61,9

61,95

62

0,5 1 1,5 2 2,5 3 3,5

28

d s

tren

gth

(M

Pa)

Orthorombic C3A (%)

28d strength - Orthorombic C3A

28d strength

Poly. (28d strength)

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A4.1.4 Aphthitalite

Figure 48 - 28d strength depending on variations in Aphthitalite content

A4.1.5 Arcanite

Figure 49 - 28d strength depending on variations in Arcanite content

y = 0,2337x2 - 2,8412x + 64,251R² = 0,9995

61,4

61,6

61,8

62

62,2

62,4

62,6

62,8

63

0,45 0,55 0,65 0,75 0,85 0,95 1,05

28

d s

tren

gth

(M

Pa)

Aphthitalite (%)

28d strength - Aphthitalite

28d strength

Poly. (28d strength)

y = 6,9988x3 - 16,367x2 + 12,945x + 58,738R² = 0,9997

61,9

62

62,1

62,2

62,3

62,4

62,5

62,6

62,7

62,8

0,4 0,5 0,6 0,7 0,8 0,9 1 1,1 1,2 1,3

28

d s

tren

gth

(M

Pa)

Arcanite (%)

28d strength - Arcanite

28d strength

Poly. (28d strength)

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A4.1.6 Langbeinite

Figure 50 - 28d strength depending on variations in Langbeinite content

A4.2 Scenarios 1d Following are scenarios where the variables are allowed to vary between the highest and lowest value

in the training set at 25 levels. Other variables are set to their mean value.

A4.2.1 Alite sum

Figure 51 - 1d strength depending on Alite content

y = 10,355x3 - 5,6197x2 + 1,6697x + 62,112R² = 0,9995

62

62,1

62,2

62,3

62,4

62,5

62,6

0 0,05 0,1 0,15 0,2 0,25 0,3 0,35 0,4 0,45

28

d s

tren

gth

(M

Pa)

Langbeinite (%)

28d strength - Langbeinite

28d strength

Poly. (28d strength)

y = -0,0078x2 + 1,1872x - 12,09R² = 0,9998

30

30,5

31

31,5

32

32,5

33

33,5

56 58 60 62 64 66 68 70 72 74

1d

str

engt

h (

MP

a)

Alite Sum (%)

1d strength - Alite Sum (C3S)

1d strength

Poly. (1d strength)

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Figure 52 - 1d strength depending on fraction of M1 to total Alite content

A4.2.2 Belite

Figure 53 - 1d strength depending on Belite content

y = -0,0109x2 + 0,969x + 10,977R² = 0,9991

31,7

31,8

31,9

32

32,1

32,2

32,3

32,4

32,5

32,6

36 38 40 42 44 46 48 50

1d

str

engt

h (

MP

a)

Fraction M1 (%)

1d strength - Fraction M1

1d strength

Poly. (1d strength)

y = -0,0073x2 - 0,0234x + 33,11R² = 0,9999

30

30,5

31

31,5

32

32,5

33

33,5

0 5 10 15 20

1d

Str

engt

h (

MP

a)

Belite content (%)

1d strength - β-Belite (C2S)

1d strength

Poly. (1d strength)

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A4.2.3 Aluminates

Figure 54 - 1d strength depending on total Aluminate content

Figure 55 - 1d strength depending on cubic C3A content

y = -0,0941x2 + 0,8309x + 30,746R² = 0,9993

30,8

31

31,2

31,4

31,6

31,8

32

32,2

32,4

32,6

32,8

4 5 6 7 8 9

1d

str

engt

h (

MP

a)

Aluminate sum (%)

1d strength - Aluminate Sum (C3A)

1d strength

Poly. (1d strength)

y = -0,0291x2 + 0,3327x + 31,029R² = 0,9995

31

31,1

31,2

31,3

31,4

31,5

31,6

31,7

31,8

31,9

32

32,1

0 1 2 3 4 5 6 7 8

1d

Str

engt

h (

MP

a)

Cubic C3A (%)

1d Strength - Cubic C3A

1d strength

Poly. (1d strength)

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Figure 56 - 1d strength depending on orthorhombic C3A content

A4.2.4 Aphthitalite

Figure 57 - 1d strength depending on the Aphthitalite content

31,3

31,4

31,5

31,6

31,7

31,8

31,9

32

0,6 1,1 1,6 2,1 2,6 3,1

1d

Str

engt

h (

MP

a)

Orthorombic C3A (%)

1d strength - Orthorombic C3A

1d strength

Poly. (1d strength)

y = -5,2194x2 + 7,5867x + 29,436R² = 0,9958

31,6

31,7

31,8

31,9

32

32,1

32,2

32,3

0,45 0,55 0,65 0,75 0,85 0,95 1,05 1,15

1d

Str

engt

h (

MP

a)

Aphthitalite (%)

1d Strength - Aphthitalite

1d Strength

Poly. (1d Strength)

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A4.2.5 Arcanite

Figure 58 - 1d strength depending on the Arcanite content

A4.2.5 Langbeinite

Figure 59 - 1d strength depending on the Langbeinite content

A4.3 Flyash Flyash is studied with various combinations of variables to increase the insight into the impact on the

combination of variables as well as possible correlations between flyash content and other variables.

y = -2,0165x2 + 6,559x + 27,803R² = 0,9977

30

30,5

31

31,5

32

32,5

33

0,45 0,55 0,65 0,75 0,85 0,95 1,05 1,15 1,25

1d

Str

engt

h

Arcanite (%)

1d strength - Arcanite

1d strength

Poly. (1d strength)

y = 19,637x3 - 17,252x2 + 2,5896x + 32,105R² = 0,9994

31,5

31,6

31,7

31,8

31,9

32

32,1

32,2

32,3

0 0,05 0,1 0,15 0,2 0,25 0,3 0,35 0,4 0,45

1d

str

engt

h (

MP

a)

Langbeinite (%)

1d strength - Langbeinite

1d strength

Poly. (1d strength)

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A4.3.1 Fly-ash content on 28d The first run is done in a model containing the following parameters:

SiO2

Al2O3

CaO

SO3

d50

Alite_sum

Alum_sum

Belite_beta

Calcite

FA_Sum

Fraction_M1

Hemi-hydrate

Portlandite

Figure 60 - 28d strength variations depending on fly-ash content

In the second run 32-2 µm was added as a parameter.

SiO2

Al2O3

CaO

SO3

32-2 µm

d50

Alite_sum

Alum_sum

Belite_beta

Calcite

y = -0,0004x4 + 0,0257x3 - 0,5356x2 + 4,1582x + 49,152R² = 0,9975

56,5

57

57,5

58

58,5

59

59,5

60

60,5

0 5 10 15 20 25

28

d s

tren

gth

(M

Pa)

FA_sum (%)

Fly-ash 28d BAS

28d strength

Poly. (28d strength)

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FA_Sum

Fraction_M1

Hemi-hydrate

Portlandite

Figure 61 - 28d strength variations depending on fly-ash content

The third run is in the model shown in Fel! Hittar inte referenskälla. including significantly fewer

parameters than the other two models.

y = -0,0003x4 + 0,017x3 - 0,3538x2 + 2,5186x + 54,383R² = 1

51

52

53

54

55

56

57

58

59

60

61

0 5 10 15 20 25

28

d s

tren

gth

(M

Pa)

FA_sum (%)

Fly-ash 28d BAS

28d strength

Poly. (28d strength)

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Figure 62 - 28d strength variations depending on fly-ash content

A4.3.2 Fly-ash on 1d strength The impact of fly-ash on the 1d strength was tested using the scenarios tool in the ANN model, using

the index shown for 1d predictions on BAS-cement.

Figure 63 - Fly-ash impact on 1d strength from HTC model

y = -5E-05x5 + 0,0028x4 - 0,0522x3 + 0,3554x2 - 0,2483x + 54,563R² = 0,9951

56,5

57

57,5

58

58,5

59

59,5

4 6 8 10 12 14 16 18 20 22

Ap

pro

xim

ated

Str

engt

h (

MP

a)

FA_sum (%)

FA_sum - 28d Final model

28d strength

Poly. (28d strength)

y = -0,0003x4 + 0,0164x3 - 0,3239x2 + 2,0216x + 19,426R² = 0,9998

18

19

20

21

22

23

24

4 6 8 10 12 14 16 18 20 22

Ap

pro

x 1

d s

tren

gth

(M

Pa)

FA_sum (%)

1d strength

1d strength

Poly. (1d strength)

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A5 – Sample selection VBA The following is the Visual Basic for Application code for the sample selection tool. Searchandfill()

selects the samples from “Data” and copies these to a separate sheet “Output”. In this case the samples

are only copied and will still be present in the original data set.

Searchandfillcut() first copies the entire data set to a new sheet, it then sorts out the samples from the

data set and removes the entire line. This leads to 3 sheets with different data sets, “Indata” with the

original data set, “Data” where the samples not selected remains, “Output” where the selected samples

is saved.

Sub Searchandfill()

'Anton Hermansson [email protected]

'Uppdaterad 2019-03-11 ANH

Dim InputRow As Long

Dim SearchRow As Long

Dim CopytoRow As Long

Dim Namn As String

Dim ws As Worksheet

Dim wb As Workbook

Dim i As Long

Dim exist As Boolean

Dim tom As Boolean

On Error GoTo Error_Exec

InputRow = 2

SearchRow = 2

CopytoRow = 2

Set wb = ActiveWorkbook

tom = False

'Output check

For i = 1 To wb.Worksheets.Count

If Worksheets(i).Name = "Output" Then

exists = True

End If

Next i

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If exists = True Then

Application.DisplayAlerts = False

wb.Worksheets("Output").Delete

Application.DisplayAlerts = True

End If

'Indata check

For i = 1 To wb.Worksheets.Count

If Worksheets(i).Name = "Indata" Then

exists1 = True

End If

Next i

If exists1 = True Then

wb.Sheets("Data").Cells.ClearContents

wb.Worksheets("Indata").Cells.Copy Destination:=Sheets("Data").Cells

Application.DisplayAlerts = False

wb.Worksheets("Indata").Delete

Application.DisplayAlerts = True

End If

Sheets("Data").Select

Set ws = wb.Sheets.Add(Type:=xlWorksheet, After:=Application.ActiveSheet)

ws.Name = "Output"

Sheets("Provnummer").Select

Dim Provnr As Long

Provnr = Cells(InputRow, 1).Value

If IsEmpty(Cells(InputRow, 1)) Then

tom = True

End If

Sheets("Data").Select

Dim Koll As Long

Koll = Cells(2, 1).Value

Sheets("Provnummer").Select

Sheets("Output").Rows(1).EntireRow.Value = Sheets("Data").Rows(1).EntireRow.Value

While tom = False

Provnr = Sheets("Provnummer").Cells(InputRow, 1).Value

If IsEmpty(Sheets("Provnummer").Cells(InputRow, 1)) Then

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tom = True

End If

Search:

Koll = Sheets("Data").Cells(SearchRow, 1).Value

If (Koll = Provnr) Then

Sheets("Output").Rows(CopytoRow).EntireRow.Value =

Sheets("Data").Rows(SearchRow).EntireRow.Value

CopytoRow = CopytoRow + 1

InputRow = InputRow + 1

SearchRow = 2

Else

SearchRow = SearchRow + 1

GoTo Search

End If

Wend

MsgBox "The request has been completed."

Exit Sub

Error_Exec:

MsgBox "Something went wrong :( Check data and request for formatting errors"

End Sub

Sub Searchandfillcut()

'Anton Hermansson [email protected]

'Uppdaterad 2019-03-11 ANH

Dim InputRow As Long

Dim SearchRow As Long

Dim CopytoRow As Long

Dim Namn As String

Dim ws As Worksheet

Dim ws1 As Worksheet

Dim wb As Workbook

Dim i As Long

Dim exist As Boolean

Dim exist2 As Boolean

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On Error GoTo Error_Exec

InputRow = 2

SearchRow = 2

CopytoRow = 2

Set wb = ActiveWorkbook

'Output check

For i = 1 To wb.Worksheets.Count

If Worksheets(i).Name = "Output" Then

exists = True

End If

Next i

If exists = True Then

Application.DisplayAlerts = False

wb.Worksheets("Output").Delete

Application.DisplayAlerts = True

End If

'Indata check

For i = 1 To wb.Worksheets.Count

If Worksheets(i).Name = "Indata" Then

exists1 = True

End If

Next i

If exists1 = True Then

wb.Sheets("Data").Cells.ClearContents

wb.Worksheets("Indata").Cells.Copy Destination:=Sheets("Data").Cells

Application.DisplayAlerts = False

wb.Worksheets("Indata").Delete

Application.DisplayAlerts = True

End If

Sheets("Data").Select

Set ws = wb.Sheets.Add(Type:=xlWorksheet, After:=Application.ActiveSheet)

ws.Name = "Output"

wb.Worksheets("Data").Copy After:=Worksheets("Output")

ActiveSheet.Name = "Indata"

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Sheets("Provnummer").Select

Dim Provnr As Long

Provnr = Cells(2, 1).Value

If IsEmpty(Sheets("Provnummer").Cells(InputRow, 1)) Then

tom = True

End If

Sheets("Data").Select

Dim Koll As Long

Koll = Cells(2, 1).Value

Sheets("Provnummer").Select

Sheets("Output").Rows(1).EntireRow.Value = Sheets("Data").Rows(1).EntireRow.Value

While tom = False

Provnr = Sheets("Provnummer").Cells(InputRow, 1).Value

If IsEmpty(Sheets("Provnummer").Cells(InputRow, 1)) Then

tom = True

End If

Search:

Koll = Sheets("Data").Cells(SearchRow, 1).Value

If (Koll = Provnr) Then

Sheets("Output").Rows(CopytoRow).EntireRow.Value =

Sheets("Data").Rows(SearchRow).EntireRow.Value

Sheets("Data").Rows(SearchRow).Delete

CopytoRow = CopytoRow + 1

InputRow = InputRow + 1

SearchRow = 2

Else

SearchRow = SearchRow + 1

GoTo Search

End If

Wend

MsgBox "The request has been completed."

Exit Sub

Error_Exec:

MsgBox "Something went wrong :( Check data and request for formatting errors"

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End Sub

A6 – IP21 fetch The IP21-fetch macros are split after the functionality. In the first ones (TransferIP21wrun() and

TransferIP21worun()) both SH and BAS is considered, the first one includes a check on the state of

the mills. If running it copies the data into the user-specified files. The second does not consider the

state of the mills but simply copies the data to the files if the cement type is correct.

The other macros have the same functions but only look at one cement type.

Sub TransferIP21wrun()

'2019-04-15 Anton Hermansson

Dim run1 As Integer

Dim run2 As Integer

Dim run7 As Integer

Dim run8 As Integer

Dim lastrow1 As Long

Dim Emprow1 As Long

Dim lastrow2 As Long

Dim Emprow2 As Long

Dim lastrow3 As Long

Dim Emprow3 As Long

Dim lastrow4 As Long

Dim Emprow4 As Long

Dim sort1 As String

Dim sort2 As String

Dim sort3 As String

Dim sort4 As String

Dim HTCBAS As String

Dim HTCSH As String

Dim HTCBASN As String

Dim HTCSHN As String

Dim IPt As String

Dim fsbas As Object

Dim fssh As Object

Set fsbas = CreateObject("Scripting.FileSystemObject")

Set fssh = CreateObject("Scripting.FileSystemObject")

On Error GoTo Error_exe

IPt = ThisWorkbook.Name

HTCSH = Application.GetOpenFilename(Title:="Specificera den aktuella modellen för

SH", FileFilter:="Excel Files *.xlsm* (*.xlsm*),")

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HTCBAS = Application.GetOpenFilename(Title:="Specificera den aktuella modellen för

BAS", FileFilter:="Excel Files *.xlsm* (*.xlsm*),")

HTCSHN = fssh.GetFileName(HTCSH)

HTCBASN = fsbas.GetFileName(HTCBAS)

If IsFileOpen(HTCSH) = True Then

Else:

Workbooks.Open (HTCSH)

End If

If IsFileOpen(HTCBAS) = True Then

Else:

Workbooks.Open (HTCBAS)

End If

Workbooks(IPt).Worksheets("Fetch").Activate

run1 = Worksheets("Fetch").Cells(4, 3).Value

run2 = Worksheets("Fetch").Cells(5, 3).Value

run7 = Worksheets("Fetch").Cells(6, 3).Value

run8 = Worksheets("Fetch").Cells(7, 3).Value

_

If run1 = 1 Then

sort1 = Workbooks(IPt).Worksheets("Fetch").Cells(4, 43).Value

If sort1 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow1 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov1 = lastrow1 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov1).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(1).EntireRow.Value

End If

If sort1 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

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ActiveSheet.Unprotect

End If

lastrow1 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov1 = lastrow1 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov1).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(1).EntireRow.Value

End If

End If

If run2 = 1 Then

sort2 = Workbooks(IPt).Worksheets("Fetch").Cells(5, 43).Value

If sort2 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow2 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov2 = lastrow2 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov2).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(2).EntireRow.Value

End If

If sort2 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow2 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov2 = lastrow2 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov2).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(2).EntireRow.Value

End If

End If

If run7 = 1 Then

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sort3 = Workbooks(IPt).Worksheets("Fetch").Cells(6, 43).Value

If sort3 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow3 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov3 = lastrow3 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov3).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(3).EntireRow.Value

End If

If sort3 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow3 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov3 = lastrow3 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov3).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(3).EntireRow.Value

End If

End If

If run8 = 1 Then

sort4 = Workbooks(IPt).Worksheets("Fetch").Cells(7, 43).Value

If sort4 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow4 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov4 = lastrow4 + 1

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Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov4).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(4).EntireRow.Value

End If

If sort4 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow4 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov4 = lastrow4 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov4).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(4).EntireRow.Value

End If

End If

Exit Sub

Error_exe:

MsgBox "Något gick snett, förlåt! :("

End Sub

Function IsFileOpen(filename As String)

Dim filenum As Integer, errnum As Integer

On Error Resume Next ' Turn error checking off.

filenum = FreeFile() ' Get a free file number.

' Attempt to open the file and lock it.

Open filename For Input Lock Read As #filenum

Close filenum ' Close the file.

errnum = Err ' Save the error number that occurred.

On Error GoTo 0 ' Turn error checking back on.

' Check to see which error occurred.

Select Case errnum

' No error occurred.

' File is NOT already open by another user.

Case 0

IsFileOpen = False

' Error number for "Permission Denied."

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' File is already opened by another user.

Case 70

IsFileOpen = True

' Another error occurred.

Case Else

Error errnum

End Select

End Function

Sub TransferIP21worun()

'2019-04-15 Anton Hermansson

Dim lastrow1 As Long

Dim Emprow1 As Long

Dim lastrow2 As Long

Dim Emprow2 As Long

Dim lastrow3 As Long

Dim Emprow3 As Long

Dim lastrow4 As Long

Dim Emprow4 As Long

Dim sort1 As String

Dim sort2 As String

Dim sort3 As String

Dim sort4 As String

Dim HTCBAS As String

Dim HTCSH As String

Dim HTCBASN As String

Dim HTCSHN As String

Dim IPt As String

Dim fsbas As Object

Dim fssh As Object

Set fsbas = CreateObject("Scripting.FileSystemObject")

Set fssh = CreateObject("Scripting.FileSystemObject")

On Error GoTo Error_exe

IPt = ThisWorkbook.Name

HTCSH = Application.GetOpenFilename(Title:="Specificera den aktuella modellen för

SH", FileFilter:="Excel Files *.xlsm* (*.xlsm*),")

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HTCBAS = Application.GetOpenFilename(Title:="Specificera den aktuella modellen för

BAS", FileFilter:="Excel Files *.xlsm* (*.xlsm*),")

HTCSHN = fssh.GetFileName(HTCSH)

HTCBASN = fsbas.GetFileName(HTCBAS)

If IsFileOpen(HTCSH) = True Then

Else:

Workbooks.Open (HTCSH)

End If

If IsFileOpen(HTCBAS) = True Then

Else:

Workbooks.Open (HTCBAS)

End If

Workbooks(IPt).Worksheets("Fetch").Activate

sort1 = Worksheets("Fetch").Cells(4, 43).Value

If sort1 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow1 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov1 = lastrow1 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov1).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(1).EntireRow.Value

End If

If sort1 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow1 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov1 = lastrow1 + 1

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Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov1).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(1).EntireRow.Value

End If

sort2 = Workbooks(IPt).Worksheets("Fetch").Cells(5, 43).Value

If sort2 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow2 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov2 = lastrow2 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov2).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(2).EntireRow.Value

End If

If sort2 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow2 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov2 = lastrow2 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov2).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(2).EntireRow.Value

End If

sort3 = Workbooks(IPt).Worksheets("Fetch").Cells(6, 43).Value

If sort3 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

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lastrow3 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov3 = lastrow3 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov3).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(3).EntireRow.Value

End If

If sort3 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow3 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov3 = lastrow3 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov3).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(3).EntireRow.Value

End If

sort4 = Workbooks(IPt).Worksheets("Fetch").Cells(7, 43).Value

If sort4 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow4 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov4 = lastrow4 + 1

Workbooks(HTCBASN).Worksheets("Data Example").Rows(lastrow).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(4).EntireRow.Value

End If

If sort4 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

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115

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow4 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov4 = lastrow4 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov4).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(4).EntireRow.Value

End If

Exit Sub

Error_exe:

MsgBox "Något gick snett, förlåt! :("

End Sub

Sub OnlySHwrun()

'2019-04-15 Anton Hermansson

Dim run1 As Integer

Dim run2 As Integer

Dim run7 As Integer

Dim run8 As Integer

Dim lastrow1 As Long

Dim Emprow1 As Long

Dim lastrow2 As Long

Dim Emprow2 As Long

Dim lastrow3 As Long

Dim Emprow3 As Long

Dim lastrow4 As Long

Dim Emprow4 As Long

Dim sort1 As String

Dim sort2 As String

Dim sort3 As String

Dim sort4 As String

Dim HTCSH As String

Dim HTCSHN As String

Dim IPt As String

Dim fssh As Object

Set fssh = CreateObject("Scripting.FileSystemObject")

On Error GoTo Error_exe

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116

IPt = ThisWorkbook.Name

HTCSH = Application.GetOpenFilename(Title:="Specificera den aktuella modellen för

SH", FileFilter:="Excel Files *.xlsm* (*.xlsm*),")

HTCSHN = fssh.GetFileName(HTCSH)

If IsFileOpen(HTCSH) = True Then

Else:

Workbooks.Open (HTCSH)

End If

Workbooks(IPt).Worksheets("Fetch").Activate

run1 = Worksheets("Fetch").Cells(4, 3).Value

run2 = Worksheets("Fetch").Cells(5, 3).Value

run7 = Worksheets("Fetch").Cells(6, 3).Value

run8 = Worksheets("Fetch").Cells(7, 3).Value

_

If run1 = 1 Then

sort1 = Workbooks(IPt).Worksheets("Fetch").Cells(4, 43).Value

If sort1 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow1 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov1 = lastrow1 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov1).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(1).EntireRow.Value

End If

End If

If run2 = 1 Then

sort2 = Workbooks(IPt).Worksheets("Fetch").Cells(5, 43).Value

If sort2 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

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117

lastrow2 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov2 = lastrow2 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov2).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(2).EntireRow.Value

End If

End If

If run7 = 1 Then

sort3 = Workbooks(IPt).Worksheets("Fetch").Cells(6, 43).Value

If sort3 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow3 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov3 = lastrow3 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov3).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(3).EntireRow.Value

End If

End If

If run8 = 1 Then

sort4 = Workbooks(IPt).Worksheets("Fetch").Cells(7, 43).Value

If sort4 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow4 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov4 = lastrow4 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov4).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(4).EntireRow.Value

End If

End If

Exit Sub

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118

Error_exe:

MsgBox "Något gick snett, förlåt! :("

End Sub

Sub OnlySHworun()

'2019-04-15 Anton Hermansson

Dim lastrow1 As Long

Dim Emprow1 As Long

Dim lastrow2 As Long

Dim Emprow2 As Long

Dim lastrow3 As Long

Dim Emprow3 As Long

Dim lastrow4 As Long

Dim Emprow4 As Long

Dim sort1 As String

Dim sort2 As String

Dim sort3 As String

Dim sort4 As String

Dim HTCSH As String

Dim HTCSHN As String

Dim IPt As String

Dim fssh As Object

Set fssh = CreateObject("Scripting.FileSystemObject")

On Error GoTo Error_exe

IPt = ThisWorkbook.Name

HTCSH = Application.GetOpenFilename(Title:="Specificera den aktuella modellen för

SH", FileFilter:="Excel Files *.xlsm* (*.xlsm*),")

HTCSHN = fssh.GetFileName(HTCSH)

If IsFileOpen(HTCSH) = True Then

Else:

Workbooks.Open (HTCSH)

End If

Workbooks(IPt).Worksheets("Fetch").Activate

sort1 = Worksheets("Fetch").Cells(4, 43).Value

If sort1 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

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119

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow1 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov1 = lastrow1 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov1).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(1).EntireRow.Value

End If

sort2 = Workbooks(IPt).Worksheets("Fetch").Cells(5, 43).Value

If sort2 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow2 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov2 = lastrow2 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov2).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(2).EntireRow.Value

End If

sort3 = Workbooks(IPt).Worksheets("Fetch").Cells(6, 43).Value

If sort3 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow3 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov3 = lastrow3 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov3).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(3).EntireRow.Value

End If

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120

sort4 = Workbooks(IPt).Worksheets("Fetch").Cells(7, 43).Value

If sort4 = "SH" Then

Workbooks(HTCSHN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow4 = Workbooks(HTCSHN).Worksheets("Data Example").Cells.Find(What:="*",

After:=Range("A1"), LookAt:=xlPart, LookIn:=xlFormulas, SearchOrder:=xlByRows,

SearchDirection:=xlPrevious, MatchCase:=False).Row

Emprov4 = lastrow4 + 1

Workbooks(HTCSHN).Worksheets("Data Example").Rows(Emprov4).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(4).EntireRow.Value

End If

Exit Sub

Error_exe:

MsgBox "Något gick snett, förlåt! :("

End Sub

Sub OnlyBASwrun()

'2019-04-15 Anton Hermansson

Dim run1 As Integer

Dim run2 As Integer

Dim run7 As Integer

Dim run8 As Integer

Dim lastrow1 As Long

Dim Emprow1 As Long

Dim lastrow2 As Long

Dim Emprow2 As Long

Dim lastrow3 As Long

Dim Emprow3 As Long

Dim lastrow4 As Long

Dim Emprow4 As Long

Dim sort1 As String

Dim sort2 As String

Dim sort3 As String

Dim sort4 As String

Dim HTCBAS As String

Dim HTCSH As String

Dim HTCBASN As String

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121

Dim HTCSHN As String

Dim IPt As String

Dim fsbas As Object

Set fsbas = CreateObject("Scripting.FileSystemObject")

On Error GoTo Error_exe

IPt = ThisWorkbook.Name

HTCBAS = Application.GetOpenFilename(Title:="Specificera den aktuella modellen för

BAS", FileFilter:="Excel Files *.xlsm* (*.xlsm*),")

HTCBASN = fsbas.GetFileName(HTCBAS)

If IsFileOpen(HTCBAS) = True Then

Else:

Workbooks.Open (HTCBAS)

End If

Workbooks(IPt).Worksheets("Fetch").Activate

run1 = Worksheets("Fetch").Cells(4, 3).Value

run2 = Worksheets("Fetch").Cells(5, 3).Value

run7 = Worksheets("Fetch").Cells(6, 3).Value

run8 = Worksheets("Fetch").Cells(7, 3).Value

_

If run1 = 1 Then

sort1 = Workbooks(IPt).Worksheets("Fetch").Cells(4, 43).Value

If sort1 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow1 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov1 = lastrow1 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov1).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(1).EntireRow.Value

End If

End If

If run2 = 1 Then

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122

sort2 = Workbooks(IPt).Worksheets("Fetch").Cells(5, 43).Value

If sort2 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow2 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov2 = lastrow2 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov2).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(2).EntireRow.Value

End If

End If

If run7 = 1 Then

sort3 = Workbooks(IPt).Worksheets("Fetch").Cells(6, 43).Value

If sort3 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow3 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov3 = lastrow3 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov3).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(3).EntireRow.Value

End If

End If

If run8 = 1 Then

sort4 = Workbooks(IPt).Worksheets("Fetch").Cells(7, 43).Value

If sort4 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

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123

End If

lastrow4 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov4 = lastrow4 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov4).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(4).EntireRow.Value

End If

End If

Exit Sub

Error_exe:

MsgBox "Något gick snett, förlåt! :("

End Sub

Sub OnlyBASworun()

Dim lastrow1 As Long

Dim Emprow1 As Long

Dim lastrow2 As Long

Dim Emprow2 As Long

Dim lastrow3 As Long

Dim Emprow3 As Long

Dim lastrow4 As Long

Dim Emprow4 As Long

Dim sort1 As String

Dim sort2 As String

Dim sort3 As String

Dim sort4 As String

Dim HTCBAS As String

Dim HTCBASN As String

Dim IPt As String

Dim fsbas As Object

Set fsbas = CreateObject("Scripting.FileSystemObject")

On Error GoTo Error_exe

IPt = ThisWorkbook.Name

HTCBAS = Application.GetOpenFilename(Title:="Specificera den aktuella modellen för

BAS", FileFilter:="Excel Files *.xlsm* (*.xlsm*),")

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124

HTCBASN = fsbas.GetFileName(HTCBAS)

If IsFileOpen(HTCBAS) = True Then

Else:

Workbooks.Open (HTCBAS)

End If

Workbooks(IPt).Worksheets("Fetch").Activate

sort1 = Worksheets("Fetch").Cells(4, 43).Value

If sort1 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow1 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov1 = lastrow1 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov1).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(1).EntireRow.Value

End If

sort2 = Workbooks(IPt).Worksheets("Fetch").Cells(5, 43).Value

If sort2 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow2 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov2 = lastrow2 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov2).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(2).EntireRow.Value

End If

sort3 = Workbooks(IPt).Worksheets("Fetch").Cells(6, 43).Value

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125

If sort3 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow3 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov3 = lastrow3 + 1

Workbooks(HTCBASN).Worksheets("Data

Example").Rows(Emprov3).EntireRow.Value =

Workbooks(IPt).Worksheets("Transfer").Rows(3).EntireRow.Value

End If

sort4 = Workbooks(IPt).Worksheets("Fetch").Cells(7, 43).Value

If sort4 = "BAS" Then

Workbooks(HTCBASN).Worksheets("Data Example").Activate

If ActiveSheet.ProtectContents Then

ActiveSheet.Unprotect

End If

lastrow4 = Workbooks(HTCBASN).Worksheets("Data

Example").Cells.Find(What:="*", After:=Range("A1"), LookAt:=xlPart,

LookIn:=xlFormulas, SearchOrder:=xlByRows, SearchDirection:=xlPrevious,

MatchCase:=False).Row

Emprov4 = lastrow4 + 1

Workbooks(HTCBASN).Worksheets("Data Example").Rows(lastrow).EntireRow.Value

= Workbooks(IPt).Worksheets("Transfer").Rows(4).EntireRow.Value

End If

Exit Sub

Error_exe:

MsgBox "Något gick snett, förlåt! :("

End Sub