title: Inﬂuence of temperature and atmosphere on polychlorinated dibenzo-p-dioxins and dibenzofurans desorption from waste incineration fly ash.
abstract: A fly ash sample was heated for 1 h to 200°C, 300°C and 400°C, in order to study the influence of temperature and gas phase composition on the removal of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from fly ash derived from municipal solid waste incineration. The tests were conducted by treating a fixed bed of fly ash both in an inert (nitrogen) and in a reducing (nitrogen+hydrogen) gas flow in a horizontal bench-scale quartz tubular reactor, heated by a surrounding tubular furnace. The results indicate that most of the PCDD/Fs in fly ash were removed by thermal treatment, especially when the temperature was higher than 300°C: the PCDD/Fs' removal efficiency attained up to 96%. PCDD/Fs dechlorination and destruction were much more important than PCDD/Fs desorption, under either inert or reducing atmosphere. At 200°C and 300°C, the experiments with reducing atmosphere yielded slightly better results than those in nitrogen; yet, this tendency was reversed at 400°C. In general, both treatment modes can fully meet the requirements regarding the concentration of dioxins in fly ash to be sent for landfill in China.
authors.affiliation: a State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering , Zhejiang University , Zheda Road 38, Hangzhou 310027 , People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.forename: Mi
authors.initials: M
authors.lastname: Yan
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Li
authors.forename: Tong
authors.initials: T
authors.lastname: Chen
authors.forename: Shengyong
authors.initials: S
authors.lastname: Lu
authors.forename: Jianhua
authors.initials: J
authors.lastname: Yan
authors.forename: Alfons
authors.initials: A
authors.lastname: Buekens
mesh_terms: D001572:Benzofurans / Q000737:chemistry*; D060729:Coal Ash; D000072338:Dibenzofurans, Polychlorinated; D017745:Incineration; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000737:chemistry; D013696:Temperature
chemical_list: D001572:Benzofurans; D060729:Coal Ash; D000072338:Dibenzofurans, Polychlorinated; D000072317:Polychlorinated Dibenzodioxins
keywords: PCDD/Fs; atmosphere; desorption; fly ash; temperature