垃圾分类前后焚烧飞灰的理化性质及重金属污染特性

Physicochemical properties and heavy metal pollution characteristics of incineration fly ash before and after refuse classification

以上海市某垃圾焚烧厂焚烧飞灰为调查对象,分析垃圾分类前后飞灰的理化性质及重金属污染特性。结果表明:垃圾分类后飞灰表面积和孔容明显降低,氯化物含量也大幅降低;除Zn、Cu外,飞灰中其他重金属含量在垃圾分类后均增加,其中Pb浸出浓度远高于GB 16889—2008《生活垃圾填埋场污染控制标准》的浓度限值,环境风险较大,必须对该飞灰进行无害化处置;由于飞灰中Pb、Cd、Zn含量和不稳定形态的变化,其在酸性条件下的浸出浓度显著增高,对环境的潜在威胁较大。

The physiochemical properties and heavy metal pollution characteristics of fly ash from a waste incineration plant in Shanghai were studied and analyzed.The results showed that the fly ash surface area and pore volume decreased obviously,and the chloride content also decreased greatly after refuse classification.Except Zn and Cu,the contents of other heavy metals increased after refuse classification,and the leaching concentration of Pb was far higher than the concentration limit of Standard for Pollution Control on the Landfill Site of Municipal Solid Waste(GB 16889-2008),which was of high environmental risk.Therefore,the fly ash must be disposed of harmlessly.Due to the change of Pb,Cd,Zn contents and their unstable forms,the leaching concentrations under acidic condition increased significantly which posed a great potential threat to the environment.