生活垃圾焚烧炉渣湿法处理前后化学特性表征

选取4个地区(编号为C、X、N、J)生活垃圾焚烧炉渣及其湿法处理后炉渣(分别称为原生炉渣及集料),针对元素成分、氧化物组分及重金属与溶盐的毒性浸出特性等开展实验分析。结果表明:(1)与原生炉渣对比,集料的化学元素含量变化较大,主要元素Si、Al、C含量均不同程度增加,而Cl、Fe及重金属Zn、Pb、Cr、Cu等含量基本降低;集料中SiO2和Al2O3均明显增加。(2)除C原生炉渣浸出液中Ni(7.62mg/L)严重超标外,其他3种原生炉渣浸出液中Pb、Cu、Ni浸出浓度均低于《危险废物鉴别标准浸出毒性鉴别》(GB 5085.3-2007)中浸出毒性鉴别标准值。与原生炉渣相比,除N集料外,其余集料浸出液中3种重金属(Pb、Cu、Ni)含量基本下降,特别是C集料浸出液中Ni浸出质量浓度下降到低于检测限;集料浸出液中Cl-和SO24-浸出浓度均下降,Cl-浸出质量浓度在C集料浸出液中下降最多,约下降72%,SO24-浸出质量浓度在J集料浸出液中下降最多,约下降86%。

Characterization of chemical characteristics of domestic waste incinerator slag before and after wet treatment

Four kinds of domestic waste incinerator slag and their aggregate after wet treatment were selected in different regions(named C,X,N,J)to analyze their chemical characteristics and leaching concentrations of heavy metals and dissolved salts.The results showed that:(1)compared with the raw slag,the contents of main elements in the aggregate changed greatly.The content of Si,Al and C increased in varying degrees,while the content of Cl,Fe and heavy metals Zn,Pb,Cr,Cu decreased.The content of SiO2 and Al2O3 in the aggregate increased significantly.(2)The leaching concentrations of Pb,Cu and Ni from the other three kinds of raw slag were all lower than the limit value of"Identification standard for hazardous wastes-identification of leaching toxicity"(GB 5085.3-2007)except that the Ni content(7.62 mg/L)in the leachate of the raw slag C was higher than its limit value.Compared with the raw slag,the contents of Pb,Cu and Ni in the leachate of their aggregate decreased except for N-aggregate,the concentration of Ni in the leachate of C-aggregate decreased below the detection limit.The concentrations of Cl-and SO42- in the leachate of aggregate decreased,the concentration of Cl-in the leachate of C-aggregate decreased the most,about72%,and SO42- in the leachate of J-aggregate decreased the most,about 86%.