生活垃圾焚烧残灰中有毒成分的排放特性（英文）

Emission characteristics of hazardous components in municipal solid waste incinerator residual ash

目的:探索中国生活垃圾焚烧残灰中重金属、氯苯、多环芳烃等有毒成分的排放特性、排放水平及相互之间的关联特性,并认识其产生、排放与焚烧炉型、焚烧条件的关联,以探索控制其危害的有效方法。方法:1.对中国几个典型的生活垃圾焚烧炉现场采样,获得多个飞灰和底渣的样品;2.通过多种不同的检测手段和方法,分别检测残灰的基本物理化学特性、氯苯、多环芳烃和主要金属元素的浓度;3.结合焚烧炉型和焚烧特性等条件,分析各有毒成分的排放特性和相互之间的关联特性。结论:1.氯苯、多环芳烃和重金属受焚烧因素影响,在残灰中的排放特性各不相同,流化床焚烧炉能消除焚烧和原始垃圾的扰动,能控制氯苯在残灰中的排放,但多环芳烃排放控制不如炉排焚烧炉;2.残灰中主要的有机有毒成分为高氯代氯苯和2至4环等少环类多环芳烃;3.氯苯和多环芳烃在残灰中的含量可能因为不同的产生机理而表现出一定的负关联特点;4.残灰中的金属主要为铝和铁等轻金属,浓度远高于重金属元素,而无毒重金属(主要为Mn、Ni、As和Zn)浓度高于有毒重金属元素(Cu、Pb和Cr),且不同金属表现出不同的对氯苯和多环芳烃的催化促进或抑制作用。

In this study, eight fly ash samples and three bottom ash samples from different areas are collected for analysis of their physicochemical properties and emission content of dioxin precursors and metals. Their surface characteristics, their effects on dioxin precursors, and important aspects of the compositions of residual ash（fly ash and bottom ash） are investigated. Poly-chlorobenzenes（PCBzs） in the fly ash of a fluidized bed incinerator（FBI） are 7.35 to 357.94 μg/kg, and in that of a fire grate incinerator（FGI） are 6.74 to 96.52 μg/kg. The concentrations in bottom ash are the same（i.e., 2.23 to 2.99 μg/kg） regardless of the furnace type. The concentrations of polycyclic aromatic hydrocarbons（PAHs） in FGI fly ash samples（0.293 to 1.783 mg/kg） are less than these in samples from FBIs（1.820 to 38.012 mg/kg）. Low boiling point PAHs（mainly 2- and 3-ringed PAHs） and high boiling point PCBzs（mainly HxCB and PeCBz） are the major constituents of residual ash. Different distributions of PCBzs and PAHs are mainly dictated by the incineration characteristics of FBI and FGI. Al and Fe, as non-toxic ＂light metals＂ are the major constituents of the residual ash, and Ni and Zn as non-toxic heavy metals play important roles in the total heavy metal. Cu, Pb, and Cr are the three major toxic heavy metals. The correlation of the metals and the dioxin precursors is discussed and distinguished.