Incineration of sewage sludge (SS) in waste incinerators is one of the main ways of SS disposal. In order to reuse the incineration bottom slag, chemical speciation and environmental risk of heavy metals of bottom slag during co-combustion of municipal solid waste (MSW) and SS should be evaluated. When co-combusted with SS, the proportion of mild acid-souble fraction of Cr, Cu and Zn in the bottom slag decreased, the proportion of reducible fraction and residual fraction increased. As for As, with the increase of sludge blending ratio, the proportion of mild acid-souble fraction increased, and the proportion of oxidizable fraction decreased rapidly. The degree of soil contamination by As and the ecological risk of As of MSW combustion bottom slag increased when co-combusted with SS, while that of Cr, Cu, and Zn decreased. Fitting formulas between environmental index of bottom slag and combustion condition were giving.

垃圾焚化炉中污泥的焚化是垃圾处理的主要方式之一。为了再利用焚化炉底渣，应评估城市固体废物（MSW）和SS共同燃烧过程中底渣重金属的化学形态和环境风险。当与SS一起燃烧时，底渣中Cr，Cu和Zn的弱酸可溶成分的比例降低，可还原成分和残留成分的比例增加。至于As，随着污泥混合比的增加，弱酸可溶部分的比例增加，可氧化部分的比例迅速减少。与SS一起燃烧时，MSW燃烧底渣的As污染土壤程度和As的生态风险，而Cr，Cu和Zn降低。