垃圾焚烧飞灰熔融过程二(口恶)英分解特性

引　言焚烧处理技术凭借其高效快捷和显著的减量效果在城市固体废弃物 (MSW )处理领域日益占有重要地位 .随着社会的进步和公众环保意识的逐渐提高 ,焚烧过程的二次污染尤其是二英的排放成为限制焚烧处理推广的瓶颈问题[1,2 ] .目前我国的垃圾焚烧过程排放二英限值为 1 0ng

DECOMPOSITION CHARACTERISTICS OF PCDD/Fs DURING MELTING PROCESS OF MUNICIPAL SOLID WASTE INCINERATOR FLY ASH

Characteristics of PCDD/Fs during the melting process of municipal solid waste incinerator fly ash were investigated by lab-scale experiments. Two kinds of fly ash samples, obtained from fixed-bed and fluidized-bed incinerators respectively, were used. The experiments were performed at various temperatures, two kinds of atmosphere (O₂ and N₂) and different residence times, and the DRE(decomposition and removal efficiency) of PCDD/Fs contained in fly ash was studied. The result revealed that approximately 99.96% dioxins were decomposed by melting under experimental condition, and the concentration of dioxins in exhaust gas of melting furnace was below the detection limit. There was an increase in temperature from 1100℃ to 1460℃ resulting in an increase of DRE of dioxins in fly ash from 99.968% to 100% in an oxidative melting atmosphere. The DRE of dioxins in the oxidative atmosphere is higher than that in inert atmosphere. The results will be helpful not only to studying the mechanism of dioxin decomposition in the melting process but also to evaluating the effect of pollution control.