De-novo formation of dioxins and furans and the memory effect in waste incineration flue gases.
The formation of dioxin (polychlorinated-rho-dibenzodioxins - PCDD) and furan (polychlorinated dibenzofurans - PCDF) in waste incineration flyash in relation to temperature has been investigated in a bench scale reactor. The PCDD/PCDF released into the exhaust gases of the reactor and trapped in a condensation and vapour phase adsorption system were also determined. The concentrations of PCDD/PCDF in the flyash were analysed in detail for all congeners and isomers including the mono-, di- and tri-PCDD/PCDF. De-novo synthesis of PCDD/PCDF was clearly seen in the flyash with large changes in concentrations of PCDD/PCDF with only small changes in temperature. Exhaust gas PCDD/PCDF were detected at all temperatures, with the maximum emission occurring at a flyash temperature of 350 degrees C, where the equivalent of over 42 times the total dioxin/furan concentration of the original flyash was lost to the vapour phase per unit mass of initial flyash. Although the desorbed species were mainly the lower mono- to tri-congener group of dioxins and furans, the desorbed dioxin/furans had a considerable toxic equivalent value.
Energy and Resources Research Institute, University of Leeds, Leeds LS2 9JT, UK.
Adrian M
AM
Cunliffe
Paul T
PT
Williams
D001572:Benzofurans / Q000737:chemistry*; D002244:Carbon; D060729:Coal Ash; D004785:Environmental Pollutants; D005740:Gases / Q000737:chemistry*; D017745:Incineration; D052638:Particulate Matter; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D014866:Waste Products / Q000032:analysis*
D001572:Benzofurans; D060729:Coal Ash; D004785:Environmental Pollutants; D005740:Gases; D052638:Particulate Matter; D000072317:Polychlorinated Dibenzodioxins; D011108:Polymers; D014866:Waste Products; C016068:polychlorodibenzofuran; D002244:Carbon