quo vadis work package 4

Quo Vadis work package 4

Sampling and sample preparation

By Geert Cuperus (Tauw)TAUWVTTINFA INSTITUTE

Contents

• Background• The new standard• Validation of sampling and sample preparation• Ruggedness testing

Background

• Inhomogenity is the issue• Shape

•Variability in shape and size

• Occurance of substances•Many elements occur concentrated in particles•“99% of a substance in 1% of the SRF”•Subsamples keep containing such particles

Background

• Many types of SRF exist• Fluff as complex example• Sampling from static lots and stockpiles mostly occur• Sampling consists of a series of steps

Sampling Mass reduction Size reduction AnalysisMass reduction

The new standard – EN 15442

• Lot size (period of production)• Number of increments• Size of increments• Distribution of increments• Sample size

The new standard – EN15442

The new standard – EN 15442

• Minimum sample size:

pVC

pgDsM

2g

395m )(

)1(

6

π

Validation of sampling

• Procedure:•Five production sites•Samplers (5) apply EN15442 to draft a sampling plan•Sampling (duplicate) of selected batches•Evaluation of plans and sample performance by Tauw•Analysis of elements by one laboratory•Statistical analysis


Sampling at 5 sites

A B

Sampler 1 Sampler 2 Sampler 3 Sampler 4 Sampler 5

A B A B A B A B


SAMPLE PREPARATION• Samples to laboratory: < 5 kg.• Particle size < 30 mm.• Sample preparation = subsampling + comminution• WP4 investigated size reduction by

•Quartering•Splitting


Sample preparationQuartering


Sample preparationSplitting


Sample

SubsampleSubsample

Primary splitting or quartering

Secondary splittingor quartering

A1 A2 A3 A4

5 sites


• Field experience:•EN15442 was easy to understand and practicable•Some samplers indicated the standard is too extensive•Useful comments resulted•Proper sampling plans were drafted


Net calorific value Repeatability 2,3%

Reproducibility 3,1%

Chlorine Repeatability 20,5%


Antimony Repeatability 40,4%


Copper Repeatability 123%

Reproducibility 123%


2,

2,

2samplingextmeasurementotaltmeasurementotalsampling sss

Validation of sampling => total standard deviationValidation of sample preparation => minus sampling

Therefore:

Validation testing on sample preparationShare sampling in total repeatabilityParameter Site 1 Site 2 Site 3 Site 4

Dry matter 100% 86% 64% -826%

NCV 100% 97% -40% -150%

Chlorine -22675637% 52% -460% -1313%

Antimony -79900% -1500% -1018% -567%

Arsenic -602% -1393%All values equal

detecion limit 86%

Lead -1764% -272% -308% 87%

Cadmium -49640% 46% -133% -351%

Chromium 40% -336% -2350% 100%

Cobalt -6411% -2067% -843% 97%

Copper -1430 0 -2% 0

Manganese 52% -5114% 71% 80%

Nickel 94% -400% -1339% 100%

Mercury -4733628% 7%All values equal

detecion limit 100%

ThalliumAll values equal

detecion limitAll values equal



detecion limit

Vanadium 100% -247% 61% 96%


• Results were used to adjust EN15442• Practicable recommendations resulted• Errors of repeatability frequently higher than errors of

reproducibility• Repeatability variation frequently negative or >100%• Other sources of error therefore have larger influence

Ruggedness testing

• Several method parameters affect the reliability of

EN15442• Of these, the lot size and the number of increments

are considered most important

Ruggedness testing on samplingStructure of the investigation

• Preparation • Research topics

•Parameters: Cl, Hg, Cu, Cr •Sampling focused on influence number of increments

(12, 24, 36, 48 and 60)•Sampling focused on influence lot size (500, 1500, 2500,

3500)

• Field work at 4 sites (Italy, Norway, Germany, Belgium)

• Sample preparation & analysis• Calculation results and reporting

Ruggedness testing

Sampling at 4 sites

5 samples

A-E

12 increments 24 increments 36 increments 48 increments 60 increments

5 samples

A-E

5 samples

A-E

5 samples

A-E

5 samples

A-E

Ruggedness testing

Sampling at 4 sites

5 samples

A-E

500 ton 1.500 ton 2.500 ton 3.500 ton

5 samples

A-E

5 samples

A-E

5 samples

A-E

Ruggedness testing on sampling Results repeatability versus number of increments

0%

50%

100%

150%

200%

250%

300%

350%

400%

0 12 24 36 48 60

Number of increments

Rep

eata

bili

ty

Chlorine

Mercury

Copper

Chromium

Average Cl, Hg, Cu and Cr

Ash

Ruggedness testing on sampling Results repeatability versus lot size

0%

50%

100%

150%

200%

250%

300%

350%

400%

450%

500%

0 500 1000 1500 2000 2500 3000 3500 4000

Lot size

Rep

eata

bili

ty

Chlorine

Mercury

Copper

Chromium

Average Cl, Hg, Cu and Cr

Ash

Ruggedness testing

• Optimum lot size is 2.500 ton (based on Cl, Hg and

Cr)• Optimum number of increments is 36• However: neither of these parameters dominate the

quality of a sample• Therefore 24 increments and lot size 1/10 of annual

production can well be applied

Conclusion

• Much work has been done now• Go and try the standard for yourself!!

THANK YOU

quo vadis work package 4

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