Quo Vadis work package 4

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Quo Vadis work package 4

• Sampling and sample preparation
• By Geert Cuperus (Tauw)
• TAUW
• VTT
• INFA INSTITUTE

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Contents

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

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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

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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
Analysis
Mass reduction
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The new standard EN 15442

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

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The new standard EN15442
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The new standard EN 15442

• Minimum sample size

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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

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Validation of sampling
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Validation of sampling

• SAMPLE PREPARATION
• Samples to laboratory lt 5 kg.
• Particle size lt 30 mm.
• Sample preparation subsampling comminution
• WP4 investigated size reduction by
• Quartering
• Splitting

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Validation of sampling
Sample preparation Quartering
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Validation of sampling
Sample preparation Splitting
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Validation of sampling
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Validation of sampling

• 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

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Validation of sampling
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Validation of sampling
Validation of sampling gt total standard
deviation Validation of sample preparation gt
minus sampling Therefore
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Validation testing on sample preparationShare
sampling in total repeatability
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Validation of sampling

• Results were used to adjust EN15442
• Practicable recommendations resulted
• Errors of repeatability frequently higher than
  errors of reproducibility
• Repeatability variation frequently negative or
  gt100
• Other sources of error therefore have larger
  influence

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Ruggedness testing

• Several method parameters affect the reliability
  of EN15442
• Of these, the lot size and the number of
  increments are considered most important

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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

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Ruggedness testing
Sampling at 4 sites
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
5 samples A-E
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Ruggedness testing
Sampling at 4 sites
500 ton
1.500 ton
2.500 ton
3.500 ton
5 samples A-E
5 samples A-E
5 samples A-E
5 samples A-E
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Ruggedness testing on sampling Results
repeatability versus number of increments
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Ruggedness testing on sampling Results
repeatability versus lot size
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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

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Conclusion

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