CIWM 2006 Conference: 1216 June

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Formation and Desorption of PCDD/PCDF in
Municipal Waste Incineration Flyash Paul T.
Williams Adrian M. Cunliffe Energy Resources
Research Institute The University of Leeds
CIWM 2006 Conference 1216 June
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1
9
O
1
9
2
8
2
8
3
7
3
7
O
O
4
6
4
6
Dioxin molecule
Furan molecule
CIWM 2006 Conference 1216 June
O
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
O
O
2,3,7,8-Tetrachloro dibenzo furan
2,3,7,8-Tetrachloro dibenzo dioxin
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Number of CDD and CDF isomers
No. Chlorine No. CDD No. CDF
Atoms Isomers Isomers
1 2 4 2 10 16
3 14 28 4 22 38
5 14 28 6 10 16
7 2 4 8 1 1
Total 75 135
CIWM 2006 Conference 1216 June
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Overall Analytical Scheme
CIWM 2006 Conference 1216 June
US EPA Method 1613 as basis for analysis
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Full PCDD/PCDF Isomer Analysis
CIWM 2006 Conference 1216 June
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PCDD/PCDF flyash desorption reactor
CIWM 2006 Conference 1216 June
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CIWM 2006 Conference 1216 June
Flyash Properties
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CIWM 2006 Conference 1216 June
Flyash - PCDD and PCDF with Nitrogen flue gas
Desorbed - PCDD and PCDF with Nitrogen flue gas
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CIWM 2006 Conference 1216 June
Desorbed - PCDD and PCDF , Congener Groups 300 C
Nitrogen flue gas
Flyash - PCDD and PCDF , Congener Groups 300 C
Nitrogen flue gas
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CIWM 2006 Conference 1216 June
Desorbed - PCDD and PCDF with Simulated flue gas
Flyash - PCDD and PCDF with Simulated flue gas
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CIWM 2006 Conference 1216 June
Desorbed - PCDD and PCDF , Congener Groups 300 C
Simulated flue gas
Flyash - PCDD and PCDF , Congener Groups 300 C
Simulated flue gas
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Conclusions
Flyash PCDD/PCDF increased to a maximum at
250-275C Consequent increase in desorbed
PCDD/PCDF mainly lower congener
groups. Simulated flue gas produced considerably
higher levels of PCDD/PCDF formation and
desorption PCDD/PCDF form on flyash by de novo
reactions in both nitrogen and simulated flue gas
CIWM 2006 Conference 1216 June
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Acknowledgements
EPSRC Mick Daniel - Environment Agency Varian
Instruments (UK)
CIWM 2006 Conference 1216 June