biorefinery- concept & applications in uk

8/7/2019 Biorefinery- Concept & Applications in UK

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FOR THE ATTENTION DR A. APFELBACHER

AUTHOR : YOUSIF ELTOM | 061413353

S C H O O L O F E N G I N E E R I N G A N D A P P L I E D S C I E N C E S ENERGY AND PRODUCTS FROM BIOMASS

WHAT IS MEANT BY THE CONCEPT OF A BIO-REFINERY, AND WHAT TYPES OF

BIO-REFINERY ARE MOST LIKELY TO FIND SUCCESSFUL APPLICATION IN THE UK?



Yousif Eltom | 0614133523

Executive Summary

This report will look in the concepts of a biorefinery and how they can be applied for commercial use

in the UK. A biorefinery is a manufacturing site involved in the refining of biomass material to yield

purified materials and molecules. With the rising demand for energy worldwide, and the peaking of oil and gas production, alternative

fuels must be sought and renewable sources are the most sustainable source. These will also help the

UK meet its commitments to the EU on carbon emissions and the Kyoto agreement.

Biorefinery have developed over time and can be classed as three different phases or generations.

- Phase 1 biorefinery have one feedstock, and one major product.

- Phase 2 biorefinery have one feedstock and can produce more than one major product

- Phase three biorefinery can process multiple feedstock and produce multiple products

There are also different specific types of biorefineries which can fit in any of these generations,

1. Whole Crop Biorefinery: A system which uses feedstock such as maize and cereals.

2. The Green Biorefinery: A system which uses wet biomass such as

3. Lignocellulose feedback Biorefinery: a system which uses naturally dry feedstock such as

cellulose-containing matter.

4. Two-Platform concept Biorefinery: A system in which both biochemical and thermo-chemical

platforms are applied.

The most feasible biorefineries to apply in the UK are the two-platform and Lignocellulose biorefinery

as these have the most feedstock available and don’t require import. The north east of the UK has a

high density of energy crops which can be used in these systems and will be the most ideal location

for a biorefinery due to this. It is also a very well connected area in terms of transport therefore

logistically easier for operation.

A type three biorefinery which can incorporate a lot more than these will be the ideal type in the UK<

however they will not set off on a commercial scale for another 15-25 years depending on

development.

Biorefineries have the potential to generate much of the UK’s energy demand but the idea of having

them must be exploited more by the UK with government taking a lead role in this.




Contents Page

Table of Figures ....................................................................................................................................... 4

1. Introduction .................................................................................................................................... 1

2. Biorefinery Definition ...................................................................................................................... 2

3. Biorefinery development ................................................................................................................ 3

3.1 Phase 1 Biorefinery ................................................................................................................. 3

3.2 Phase 2 Biorefineries .............................................................................................................. 3

3.3 Phase 3 Biorefineries .............................................................................................................. 4

4. Types of Biorefineries ..................................................................................................................... 4

4.1 Whole Crop Biorefinery .......................................................................................................... 4

4.2 The Green Biorefinery ............................................................................................................. 5

4.3 Lignocellulose feedstock Biorefinery ...................................................................................... 6

4.4 Two-Platform concept Biorefinery.......................................................................................... 6

5. Feedstock ........................................................................................................................................ 8

5.1 Waste ...................................................................................................................................... 8

5.2 Energy Crop ............................................................................................................................. 8

5.3 Algae ..................................................................................................................................... 10

6. Products ........................................................................................................................................ 11

6.1 Energy and Fuel ..................................................................................................................... 11

6.2 Chemicals .............................................................................................................................. 11

6.3 Materials ............................................................................................................................... 11

7. UK Location ................................................................................................................................... 13

7.1 Location ................................................................................................................................. 15

8. Discussion ...................................................................................................................................... 16

9. References .................................................................................................................................... 17




Table of FiguresFigure 1. An Example of how Biomass can be used to reduce carbon emissions .................................. 1

Figure 2. Simple Biorefinery flowsheet ................................................................................................... 2

Figure 3.Phase 1 Biorefinery ................................................................................................................... 3

Figure 4.Phase 2 Biorefinery ................................................................................................................... 3

Figure 5. Schematic for a Whole Crop Biorefinery ................................................................................. 4

Figure 6. Schematic for a Green Biorefinery ........................................................................................... 5

Figure 7. Schematic for a LCF Biorefinery ............................................................................................... 6

Figure 8. Basic Schematic for a Two-Platform Biorefinery ..................................................................... 6

Figure 9. Wood that can be used as biomass ......................................................................................... 8

Figure 10. Mature Willow SRC ............................................................................................................... 9

Figure 11. How Algae can be used in the future as a fuel .................................................................... 10

Figure 12. Biodiesel is currently being used as a replacement fuel ...................................................... 11

Figure 13. Detailed breakdown of products of a Biorefinery ............................................................... 12

Figure 14. Locations of current UK Biorefineries .................................................................................. 13

Figure 15. Table to show the capacities and feedstock of UK Biomass production ............................. 15

http://e/4th%20Year%20MEng%20ChemEng/Energy%20&%20products%20from%20biomass/Yousif%20Biorefinery.doc%23_Toc276721986

http://e/4th%20Year%20MEng%20ChemEng/Energy%20&%20products%20from%20biomass/Yousif%20Biorefinery.doc%23_Toc276721986




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1. IntroductionAccording to the International Energy agency, the worldwide energy demand will rise by 45% from

2006 to 20301. With oil and gas production either at its peak or very close to peaking2, the need for

sustainable renewable energy is required with immediate effect.

The UK is currently seeking to meet its targets under the Kyoto agreement to reduce its carbon

emissions below the 1990 emissions before 2008-2012, and also of the EU agreement for “a 20%

share of renewable energies in overall EU energy consumption by 2020; a 10% minimum target to be

achieved by all Member States for the share of bio fuels in overall EU transport petrol and diesel

consumption by 2020, to be introduced in a cost-efficient way”3

With both the rising demand for energy and the UK’s commitments to reducing carbon emissions

and meeting its EU targets, much research is being undertaken in the available sources of

sustainable fuel. One option which has been forecasted to meet up to 10% of the future world

energy demand is the use of biomass to produce energy4. Biomass can be used in Biorefineries to

produce energy, fuel, and a wide variety of chemicals5.

Figure 1. An Example of how Biomass can be used to reduce carbon emissions




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2. Biorefinery DefinitionAccording to the NNFCC ( National Non-Foods Crop Centre)

6 there isn’t a strict definition of the term

Biorefinery due to the constant development’s involved however the closest description of a

Biorefinery is ‘a manufacturing site involved in the refining of biomass material to yield purified

materials and molecules. This conversion can be achieved using biological or thermochemical

processing or a mixture of both.’

These biorefineries have a similar concept to a traditional oil refinery whereby a raw material is

fed into a process and the output is an end-product which is in demand and economically

feasible to manufacture.

A simple flowsheet to show how biomass is refined in a Biorefinery is illustrated below:

Figure 2. Simple Biorefinery flowsheet7

Biomass feedstock consists of three main components, lignin, cellulose and hemicellulose8. After

being pre treated biomass undergoes a series of biological or thermochemical conversion into a

number of value-added chemicals, fuels, and can also provide heat and electricity.




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3. Biorefinery development The concept of Biorefineries has long been a subject of much research and development, especially

when similarities are drawn with the conventional petrochemical refineries.

When the first model of a Biorefinery was developed it was simple, and over time and with much

research developed into the different forms of Biorefinery ideas we have before us today. In brief

the development of Biorefineries can be split into different phases; 1, 2, and 39.

3.1 Phase 1 Biorefinery

A phase 1 Biorefinery is a basic refinery which only has one type of feedstock, has fixed process

abilities and can only produce one major product. Many of these exist across Europe and a typical

example is that of the biodiesel process which is shown below9.

Figure 3.Phase 1 Biorefinery9

3.2 Phase 2 BiorefineriesA phase 2 Biorefinery is similar to a phase 1 Biorefinery as it can only process one feedstock;

however it has the ability to produce more than one major product10

. An example of a phase 2

Biorefinery is the production of multiple of chemicals from cereal grains; a block diagram is shown

below.

Figure 4.Phase 2 Biorefinery9




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3.3 Phase 3 Biorefineries

Phase three Biorefineries are seen as the future of Biorefineries; these will be able to process a

multitude of feedstock types and also produce a variety of chemicals, fuels and energy11

. They give a

great amount of flexibility with meeting market demands which is very lucrative to any company.

There are not any commercial scale phase 3 Biorefineries at the moment however research and

development across the world is focussed on developing them into a viable and feasible

establishment. There are four types of phase three Biorefineries which will be looked at further.

4. Types of Biorefineries

Currently there is believed to be four different types of Biorefineries11

. These are:

5. Whole Crop Biorefinery: A system which uses feedstock such as maize and cereals.

6. The Green Biorefinery: A system which uses wet biomass such as

7. Lignocellulose feedback Biorefinery: a system which uses naturally dry feedstock such as

cellulose-containing matter.

8. Two-Platform concept Biorefinery: A system in which both biochemical and thermo-

chemical platforms are applied.

4.1 Whole Crop Biorefinery

12

Figure 5. Schematic for a Whole Crop Biorefinery12




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A whole crop Biorefinery will use cereals such as wheat, corn, maize and rape. It will then convert

the whole plant (both straw and grain) into energy, chemicals, materials and food.13

The detailed schematic (figure 5) shows the complexity involved with this type of process, firstly the

seed and straw must be separated and undergo different processes. The seeds are processed toproduce starch before undertaking chemical conversion to ethanol and a whole range of products.

The straw is then processed and separated into lignin, hemicellulose, and cellulose; these can then

be refined according to the set up of a ligno-cellulose Biorefinery.

4.2 The Green Biorefinery

Figure 6. Schematic for a Green Biorefinery13

A green Biorefinery is a form of a phase 3 Biorefinery for which much study has been undertaken in

order to develop it. A green Biorefinery takes ‘green biomass’ such grass, algae, Lucerne and uses

combining technologies to produce energy, chemicals and fuel14

. The biomass is usually pressed into

fibre-rich press cake and green juice. The press juice contains many useful chemicals such as organic

acids, amino acids and dyes. It can also be fermented to produce further chemicals.

The press cake has many applications; it can be used as fodder, fuel to produce biogas and also as a

raw material to produce many chemicals and hydrocarbons15.




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4.3 Lignocellulose feedstock Biorefinery

Figure 7. Schematic for a LCF Biorefinery

A Lignocellulose Biorefinery uses ‘nature dry’ feedstock and cellulose-containing feedstock such as

straw, chaff, wood, corn Stover and reed grass16

. The feedstock is split into the main components of

biomass; lignin, hemicellulose, and cellulose. These then undergo many processes and converted

into an array of energy and chemical products.

4.4 Two-Platform concept Biorefinery

Figure 8. Basic Schematic for a Two-Platform Biorefinery




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The two platform concept refinery is a form of an integrated Biorefinery in which a starch

fermentation setup and a lingo-cellulose process are adapted. The typical feedstock for this type of

Biorefinery is ‘cereal’ and is fed whole into the process. The first stage is to separate the seed from

the straw before further processing. The seed is usually processed to produce starch and a range of

chemicals including ethanol13.

The straw is then processed according to the Lignocellulose to produce the variety of chemicals it is

able to achieve.




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5. Feedstock Various forms of feedstock can be used with Biorefineries, but most biomass has certain

characteristics which differ from the feedstock used in traditional petrochemical Biorefineries.

Biomass feedstock is generally widely distributed with areas of low density and is only available

seasonally. However the key distinguishing property is the fact that biomass is seen as a sustainable

and renewable source as crude oil and natural gases are finite.

The types of feedstock used can be broken down into two main categories, waste and energy crop.

5.1 Waste

Municipal Solid Waste (MSW): this is waste which is thrown out as rubbish, although not all of it is

suitable for use as biomass. Currently in the UK 2.5 million tonnes of MSW is used for energy

recovery, with the potential for this to increase by 400%17

.

Waste from Forest Management: waste wood and crops that otherwise go to landfill can be used to

recover energy. It is estimated that nearly 5 million tonnes of waste wood could be used as

biomass17

.

Figure 9. Wood that can be used as biomass3

Animal waste: In the UK around 3 million tonnes of animal wastes and slurries are generated

annually. If 50% of this was used as biomass in anaerobic digesters, up to 1.1TWh of electricity can

be produced and a carbon saving of over 0.13MtC annually17

.

Other sources in this category include waste from the food industry, such as vegetable oils.

5.2 Energy Crop

These are dedicated energy crops which are grown solely for the purpose of generating bio

products18

. They tend to have a considerable level of sugars, Lignocellulose, starches and oil which in

turn give the crop relatively high energy content18

.

The main form of energy crops are short rotation coppice (SRC) and miscanthus. The UK currentlyproduces around 25,000 tonnes per annum of both SRC and miscanthus

19, with the government




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targets aimed to utilise 1 million hectares to be used for non-food use it is estimated up to 8 million

tonnes of energy crops can be produced for purpose of generating biofuels17

.

Short Rotation Coppice (SRC): SRC consists of a variety of willow or poplar which are usually densely

planted and highly yielding. These are harvested anytime between a 2-5 year period, and aplantation can be viable for up to 30 years

20.

Miscanthus: Miscanthus is a highly-yielding energy crop which has rapid growth which can be

harvested annually, and grows to over three metre21

.

Energy Crops have many advantages22

:

- They contain high amounts of sugars meaning they can be converted into energy using

advanced technologies

- They produce high volumes of fuel per tonne compared to corn and agricultural waste, upto three times

- The land on which they are grown does not have to be productive therefore they can be

planted in areas close to where they will be refined and used. This reduces the logistical

issues involved with transporting bulk materials.

Figure 10. Mature Willow SRC 20

Some forms of energy crop have a natural ability to undergo a process known as phytoremidiation.

This is a concept whereby the plants have a natural ability to render harmless and mitigate any

contaminants which many be in the soil23

. As a clean cost effective way to remove contaminants

much research is currently being undertaken to develop this field24

.




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5.3 Algae

Due to the methods of formation for algae, it has a potential to be a key supplier of biomass for

Biorefineries. Algal fuel can be cultivated in open pond systems and photo bioreactors; however

there are still mane complications in the process and its productions is not yet commercially viable.

Figure 11. How Algae can be used in the future as a fuel




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6. ProductsThe products produced from a Biorefinery must be in demand, and they should be capable of

replacing the products formed from current petro refineries. The main products formed by a

Biorefinery can be split into three categories25

.

6.1 Energy and Fuel

Energy can be created in the form of heat or electricity, the heat can be used in other parts of the

process where heat is needed and the electricity can be fed into the grid network. The Energy can

also be created from the fuels which are formed in the process. The fuels can be in the forms of

solid, liquid or gas and have many applications.

Figure 12. Biodiesel is currently being used as a replacement fuel

6.2 Chemicals

A huge array of chemicals can be produced by Biorefineries, these include the likes of activated

carbon which can be used in many industries, and also speciality chemicals which tend to be value-

added products and drive high profits.

6.3 Materials

Like the chemicals produced in a Biorefinery, the variety of materials produced is also large. Dyes,

pigments, oils, paints and inks are all included in the list of materials which can be produced. This is

dependant of the phase of Biorefinery, usually phase 3.




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Detailed breakdowns of the products produced are shown below.

Figure 13. Detailed breakdown of products of a Biorefinery




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7. UK LocationAlthough the UK is the centre for much of the research being undertaken in the development of

Biorefineries, it is still falling being in the exploitation of the concept of an integrated Biorefinery26

.

The main forms of Biorefineries in the UK at the moment are bio-ethanol and bio-diesel producing

site, which have been established for some time now.

Both of these refineries are either a phase 1 or phase 2 Biorefinery; however it must be noted that

to date there is yet to be any phase 3 or 3rd

generation Biorefineries in the world. According to the

NNFCC the current known UK production of bio fuels is 614,000 tonnes/year, with another 1,900,000

tonnes/year either in construction, planning or proposition27

. When taken as a percentage of the UK

transport fuel demand for 2010 (37 million tonnes/year) this is just under 7% of the UK demand. To

date all of these ventures have been successful and economically viable for the companies who

continue expanding in this field which leads to the topic of what types of Biorefinery are more likely

to find success in the UK?

Figure 9 shows us the locations of the current Biorefineries in the UK, and also their capacities. More

importantly the corresponding table shows us exactly what capacities are being run at these

facilities.

Figure 14. Locations of current UK Biorefineries28




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Map

reference

Company Location Feedstock Total Installed

Capacity (MW)

1 Scottish Power Longannet Energy crops 2400

2 Scottish Power Cockenzie Energy crops 1200

3 Alcan Smelting

and Power UK

Lynmouth Woodchip 420

4 Sembcorp Middlesbrough Small round wood, recycled wood, sawmill co-

products, SRC willow

42

5 SSE Ferrybridge Biomass 300

6 British Energy Eggborough SRC willow 1960

7 Drax Selby Energy crops, virgin timber, olive kernels etc. 500**

8 Centrica Glanford Brigg Distillate 272

9 EDF, West

Burton

Power Ltd.

Retford Wood, SRC 2000

10 EDF, Cottam

Power Ltd.

Retford Wood, SRC 2000

11 E.ON Ratcliffe-On-Soar,

Nottingham

Biomass 2000

12 EPR Elean Business

Park , Sutton

Straw and energy crops 40

13 E.ON Kingsnorth, Kent Cereal co-products 2000

14 Npower Cogen

Ltd.

Aylesford, Kent Pulp and paper residues 100

15 RWE Npower Tilbury, Essex Sawdust and Palm kernel expeller (PKE) 1100

16 RWE Npower Littlebrook D, Kent Biomass 2200

17 SSE/Slough

Estates

Slough Woodchip, biomass and waste paper 80

18 RWE Npower Didcot ‘A’,

Oxfordshire

Shea-nut meal, sawdust, PKE and olive pellets 2100

19 RWE Npower Aberthaw ‘B’, Vale

of Glamorgan

Sawdust, PKE and woodchip 1600




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20 Welsh Power,

Uskmouth

Power Ltd.

Newport Woodchip and shea pellets 393

21 E.ON Telford Woodchip, shea nut meal, palm and

Miscanthus

970

22 UPM Shotton Mill Biomass and pulp/paper residues 20

23 SSE Fiddler’s Ferry,

Warrington

PKE, olive pellets, citrus pulp pellets and wood 2000

24 E.ON Lockerbie 60% saw-mill co-products and small round

wood, 20% SRC willow, 20% recycled fibre

(from wood product manufacture)

44

Figure 15. Table to show the capacities and feedstock of UK Biomass production

Highlighted in this table are the top rated capacity Biorefineries in the UK, and from the 24 listed,

the top 9 in terms of capacity have been highlighted. Of these 9 Biorefineries, 6 clearly use Biomass

or energy crops as their feedstock, and from the 24 listed Biorefineries, 16 use energy crops or

biomass as their feedstock. It is clear to see from this that the main source of feedstock in the UK at

the moment is energy crops, and this is mainly due to their advantages as stated earlier in the

report.

7.1 Location

There are many factors which must be taken into consideration when locating a Biorefinery; more

importantly are the factors of sourcing the feedstock and transportation infrastructure available.

From figure 9 above it is clear to see that the north eastern region of the UK has the most potential

for providing energy crops for the use in biorefineries. In order for the UK to climb the Biorefinery

industry ladder, these densely populated energy crop potentials must be fully exploited and the

importing of biomass kept to a minimal.




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8. DiscussionMany forms of Biorefineries are available to be used in the UK, and currently operations are

expanding across the country. The best available Biorefineries for use in the UK are two-platform

Biorefinery and the ligno-cellulose Biorefinery as they consume the types of feedstock which may be

readily available in the UK and does not require any importing of feedstock.

The availability of feedstock in the UK is currently an issue, however salvaging much of the waste

could provide an immediate source of biomass for Biorefineries, and to ensure Biorefineries provide

a cost effective solution to the world’s carbon emission the importing of feedstock must be kept to a

minimal.

The UK has a very good transportation network as it is with most areas easily accessible by road,

train or sea. This means the location of a Biorefinery can be broad, however location close to the site

of feedstock is important to minimise transportation costs and also carbon emissions. If the

Biorefinery will not further process the bio products it is also ideal for it to be located close to a site

of further processing in order to minimise costs and emissions.

The north east of the UK has the highest density of energy crops, and this is a vital aspect which

must be exploited to maximise UK production of bio products. The UK has many phase 1

Biorefineries but it is important it enters the phase 2 market and build a strong foundation for what

will be a bright future in the phase 3 Biorefinery industry which will not really become commercially

viable for an further 15-25 years depending on the advancements made in the areas of research and

development.

The concept of applying Biorefineries in the UK will help generate some of the UK’s energy demands

and also reduce carbon emissions. The use of biomass can also cater for the speciality chemicals

industry and replace downstream operations that current operate by petrochemical refineries.




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9. References

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2Sorrell,S. (2010). Global oil depletion:A review of the evidence. Energy Policy . 38, p5290.

3Department for Environment, Food and Rural Affairs. (2007). UK Biomass Strategy. p8.

4Tanaka,N. (2008). World energy outlook. International energy agency p159.

5King,D. (2010). The future of Industrial Biorefineries. World Ecomomic Forum.p6.

6Smith,W. (2007). State of the Art in Biorefinery Development. Tamutech Consultancy . p4.

7James H. Clark, Fabien E. I. Deswarte and Thomas J. Farmer. (2009). the integration of

green chemistry into future bio refineries. Bio fuels, Bioprod. Bioref . 3, p73.

8James H. Clark, Fabien E. I. Deswarte and Thomas J. Farmer. (2009). The integration of

green chemistry into future biorefi neries. Bio fuels, Bioprod. Bioref . 3, p77

9Clark. Deswarte,F. (2008). The Biorefinery Concept–An Integrated Approach. Introduction

to Chemicals from Biomass. 1 , p6.

10 Clark. Deswarte, F. (2008). The Biorefinery Concept–An Integrated Approach. Introductionto Chemicals from Biomass. 1 , p7

11Clark. Deswarte,F. (2008). The Biorefinery Concept–An Integrated Approach. Introduction

to Chemicals from Biomass. 1 , p9

12Kamm,K. Kamm,M. (2004). Principles of bio refineries. Appl Microbiol Biotechnol . 64 (1),

p143

13Kamm,K. Kamm,M. (2004). Principles of bio refineries. Appl Microbiol Biotechnol . 64 (1),

p144

14Smith, W. (2007). State of the Art in Biorefinery Development. Tamutech Consultancy .

P74.

15Georgakaki, A. (2008). Advanced Biorefinery Concepts: A Feasibility and Reality Check.

Biosynergy , p14.

16Smith, W. (2007). State of the Art in Biorefinery Development. Tamutech Consultancy .

P75.

17Gill, B. (2005). Report to Government. Biomass Task Force. 1, p14




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18DEFRA. (2004). Growing Short Rotation Coppice. Best Practice Guidelines for Applicants to

Defra’s Energy Crops Scheme. 1 (1), p5.

19Gill, B. (2005). Report to Government. Biomass Task Force. 1, p15

20DEFRA. (2004). Growing Short Rotation Coppice. Best Practice Guidelines for Applicants to

Defra’s Energy Crops Scheme. 1 (1), p6.

21John, C (2004). Miscanthus biomass production for energy in Europe. Global Change

Biology . 10, p509.

22BP. (2010). Dedicated Energy Crops. Available:

http://www.bp.com/sectiongenericarticle.do?categoryId=9030047&contentId=7055177.Last accessed 24th October 2010.

23Lasat, M. (2000). PHYTOEXTRACTION OF METALS FROM CONTAMINATED SOIL: A REVIEW

OF PLANT/SOIL/METAL INTERACTION AND ASSESSMENT OF PERTINENT AGRONOMIC

ISSUES. Journal of Hazardous Substance Research. 2 (5), p1.

24Xiao-Zhang,Y. Pu-Hua,Z. Yong-Miao,Y. (2006). The potential for phytoremediation of iron

cyanide complex. Ecotoxicology . 14 (1), p461.

25

Dr John Brammer Lecture Notes, Combustion and Gasification

26Reynolds,J. (2007). A North East UK View Bio refining Scoping Study Report. The

Biorefinery Opportunity . p8.

27NNFCC. (2010). UK Bio fuel Production Facilities: Status Update. NNFCC Bio fuels

Newsletter .p3.

28NNFCC. (2010). NNFCC Publication. UK Operational Biomass Processing Facilities. p 1.

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