Jussi RantaProgress report of QuoVadis WP 5 & 6, parts SRF

- Bulk density, - density of pellets and briquettes and

- metallic aluminium

QuoVadis consortium meeting, ISPRA 14.12.2006

2

Bulk density - ruggedness, resutls

Ruggeness of bulk density was measured using 2 container sizes and 2 operators - some results:

– SRF typically has larger particle size than 12 mm and normally only larger container is relevant

– Large container systematically produced larger values– Shock (from 1 to 5 shocks) exposure systematically increased

bulk density (high compressibility of SRF fuels)– Large differences were obserwed in between-operator results

3

Bulk density - ruggedness, recommendations

Due to material heterogeneity the method is quite sensitive to change of different parameters and not always statistically robust.

– Measurement conditions and instructions must be followed carefully.

– It is useful, due to lower measurement variance, to use only larger (50 l) container.

– Consider if small container is needed for SRF fuels

4

Bulk density Validation - future work

Work continues with validation according to "DIN ISO 5725-5 Part 5 Design for heterogeneous materials"

– 5 SRF samples have been identified and collected– All having particle size larger than 12 mm– Validation test using large container have been started and will

be finished appr. March 2007

5

Design for heterogenous material like SRF according to DIN ISO 5725-5, Part 5

Laboratory / Operator  

Level 1 /Type results 1,2

Level 2 / Type Level 3 / Type Level 4 / Type Level 5 / Type

    REF 1 EWA Pellet L&T SRF L&T DW EKO

    1 2 1 2 1 2 1 2 1 2

1/EPResult 1                    

Result 2                    

2/JKResult 1                

Result 2                

3/IIResult 1 144,1 146,2 344,7 348,7 115,9 124,5 194,2 185,1 191,5 171,7

Result 2 158,1 155,7 349,9 351,4 129,2 131,6 200,9 187,4 168,8 163,4

4/JRResult 1         115,7 114,5        

Result 2         109,9 109,4        

5/JKResult 1                    

Result 2                    

6Result 1                    

Result 2                    

7Result 1                    

Result 2                    

  level average 151,1 151,0 347,3 350,0 117,7 120,0 197,6 186,3 180,2 167,6

  gen. average 151,0 348,7 118,8 191,9 173,9

Bulk density Validation - example

6

Density of pellets and briquettes- ruggedness results

• Ruggedness was tested using available biomass and SRF hard pellets

• The proposed test methods were found to be robust and well suited for SRF fuels as well. However, result variance was clearly larger for SRF pellets than for biomass pellets.

• No SRF briquettes identified

7

Pellet (Particle) density ruggedness results - example

Coefficient of variation vs. pellet type and measurement parameters

0,00

2,00

4,00

6,00

8,00

10,00

12,00

14,00

16,00

18,00

1 2 3 4 5 6 7 8 9

Number of repeats

CV

, %

Light Pellet, M Bark pellet, M

SRF pellet, M SRF pellet, B

8

Density of pellets and briquettes - validation

• So far only one sample obtained and second one expected. More is needed for proper validation

• Uncertain if reasonable number of samples can be found• No SRF briquettes identified

9

Density of pellets and briquettes - recommendations

• Consider deleting of density measurement for briquettes. Rationale:

• No SRF briquettes identified• SRF use in large scale, no similar need for measurement

method than in case of biomass (domestic use of biomass pellets and briquettes, handling, dusting etc.)

10

Metallic aluminium, method A - ruggedness

Particle size, mm

Sample

Size, g

Boiling time, h

0,5 1 1

1,0 2 1,5

1,5 3 2

11

Metallic aluminium, method A - ruggedness

Ruggedness was tested for particle size, treatment time and test portion size

– The method was be robust against particle size and treatment time in hot alkali.

– It was noticed that largest effect on ruggedness was with test portion size, which was varied from 1 to 3 grams. With larger test portions, lower results were achieved. Reason may lie in the fact that if metallic aluminium is low in concentration and in relatively large particles, the number of aluminium particles may vary from test portion to test portion. And this variation is likely to be larger for smaller test portions.

12

Metallic aluminium, method A - recommendations

Due to this heterogeneous nature of SRF samples containing elements in metallic form it is recommended that as large test portions are used as practically possible. This is specially the case with low concentrations of metallic aluminium. Recommendation is to use larger, up to 5 g test portion, if metallic aluminium is not visible in the sample. Lower amount may be used if metallic aluminium is clearly visible.

13

Metallic aluminium, method A - Validation

One problem in ruggedness testing was low concentration of Al

For validation we need to know what levels are of relevance and how to obtain these samples

Samples provided so far cannot be used for validation

END