Analysis of heavy metals in slag from one municipal solid waste incinerator in Shanghai

摘要

This study aimed to develop a methodology for analysis of heavy metals in municipal solid waste incineration (MSWI) slag. It performed analysis of composition of heavy metals, leaching toxicity, leaching behavior as a function of pH and specification distribution of Pb, Cd, Cu and Zn. It was found that content of heavy metals followed the decreasing sequence of Zn > Pb > Cu > Cd. MSWI slag was not a hazardous solid waste as leaching concentrations of the four heavy metals didn't exceed the limit described in Identification Stand of Hazardous Waste - Identification of leaching toxicity. Slag may do harm to the environment at the existence of acids as soluble phases (carbonate occluded and exchangeable) accounted for around 40%, 67%, 45% and 18% for Zn, Pb, Cd and Cu, respectively, and thus an acidic environment could enhance leaching of the four heavy metals which was evidenced by leaching results as a function of pH.