生活垃圾焚烧飞灰中重金属的稳定化及其机理研究  

Stabilization and mechanism of heavy metals in municipal solid waste incinerator fly ash

作　　者：孙杨雨 焦春磊[1,2] 谭笑 邹德勋[1,2] 林爱军 

机构地区：[1]北京市高等学校环境污染控制与资源化工程研究中心 [2]北京化工大学化学工程学院,北京100029

出　　处：《中国科学：化学》2016年第7期714-722,共9页SCIENTIA SINICA Chimica

基　　金：国家自然科学基金(编号:40901149);环保公益性行业科研专项(编号:201309022)资助项目

摘　　要：以中国西南某垃圾焚烧发电厂所产生的飞灰为研究对象,分别考察了二乙基二硫代氨基甲酸盐(DTC)和磷酸钠单一添加处理以及混合联用处理对飞灰中重金属的稳定化效果,运用X射线衍射(XRD)、傅里叶转换红外线光谱(FTIR)、扫描电子显微镜(SEM)和分级提取等分析方法对飞灰中重金属的稳定化机理进行研究.研究结果表明,DTC能有效稳定Cd、Cu和Ni,磷酸钠则对Pb的稳定化效果较好,用1%的DTC和8%的磷酸钠混配来处理飞灰,能使其中Cd、Cu、Ni和Pb的浸出浓度都达到生活垃圾填埋标准.稳定化药剂与飞灰中重金属结合没有生成晶体,而是重金属进入螯合剂有效基团内,反应生成絮状沉淀穿插、附着在飞灰颗粒物的孔隙和表面,并且处理后飞灰中Cd、Cu、Ni和Pb的形态均呈现出由不稳定态向稳定态转化的趋势,使飞灰中重金属的浸出浓度降低.This paper takes fly ash obtained from a municipal solid waste incineration power plant in Southwest China as the research object and studies the stabilization effect of heavy metals in it treated by different dosages of diethyl dithiocarbamate （DTC） and sodium phosphate. The mechanism of stabilization is investigated using XRD, FTIR, SEM and sequential extraction. The results indicate that DTC could effectively stabilize Cd, Cu and Ni, and sodium phosphate could stabilize Pb better. With the additive amount of 1% DTC plus 8% sodium phosphate, the concentrations of Cd, Cu, Ni and Pb in leachate of the fly ash samples could meet the demand of co-disposal in sanitary landfill. The chelating agent combined with heavy metals in the fly ash could not generate crystals, but the heavy metals could combine with the DTC＇s effective radical group, generating floc in the pore or on the surface of the fly ash, and the chelating agent could transform heavy metals from unstable to stable state, decreasing their concentrations in the leachate of the fly ash.

关 键 词：飞灰 重金属 稳定化 机理 

分 类 号：X799.3[环境科学与工程—环境工程]