分析了上吸式固定床气化炉处理生活垃圾过程产物中二噁英的分布特征，系统 研究了垃圾气化过程中二噁英的形成和迁移机制． 结果表明:气化炉出口烟气经湿法洗涤 和电捕焦油器净化后，其中的二噁英含量为 0. 48 ng I-TEQ/Nm 3 ，洗涤水和焦油中的二噁 英含量较高，分别为 8259. 50ng I-TEQ/L 和5941. 84ng I-TEQ/kg;垃圾气化过程中二噁英 的总排放因子为 165. 86μg I-TEQ/t-垃圾，其中96. 06%通过炉渣排放，3. 58%存在于焦油 中，仅 0. 35%随烟气排放，因此炉渣是二噁英的主要排放源，这与生活垃圾焚烧过程中二 噁英的排放不同． 二噁英的同系物分布特征表明，炉渣、洗涤水、焦油、烟气中的二噁英主 要在气化炉内合成，而不是在烟气净化过程中． 运用上吸式固定床气化炉处理生活垃圾过 程中，控制炉内二噁英的产生是减少二噁英类物质排放的关键．

The formation and migration of dioxins were investigated by analyzing the distribution characteristics of dioxins in all output products from a updraft fixed bed gasifier for disposing domestic solid waste.The results show that after the purification of the wet scrubbing coupled with an electric tar precipitator,the content of dioxins in the flue gas of the gasifier output is 0. 48ng I-TEQ/Nm 3 ,and the contents of dioxins in the scrubbing water and the tar are higher,which are respectively 8259. 50ng I-TEQ/L and 5941. 84ng I-TEQ/kg,and that the total emission factor of dioxins in the gasifier system is 165. 86μg I-TEQ/t,of which 96. 06% is emitted by the residual,3. 58% by the tar,and only 0. 35% is discharged with the flue gas.Therefore,the residue is the main emission resource of dioxins,which is obviously different from the municipal solid waste incineration.The similar distribution characteristics of dioxins in the residues,the scrubbing waste,the tar and the flue gas indicate that dioxins are generated in the gasifier chamber rather than the process of flue gas cleaning.Thus,it is suggested that the effective control of the generation of dioxins within the gasifier chamber is the key when the updraft fixed bed gasifier is used to dispose solid waste.