China Nonferrous Metallurgy

With the rapid development of Chinas economy and the improvement of urbanization level, waste incineration has gradually become a main way for harmless treatment of urban domestic waste, but the produced fly ash, due to its high leaching toxicity and high heavy metal concentration, is classified as a hazardous waste. The harmless disposal and recycling of incineration fly ash have become a social focus. In this paper, the source, harm and current situation of production and discharge of fly ash were discussed; the focus was given on the harmless disposal technologies and recycling methods of fly ash, involving solidification/stabilization technology, separation and extraction technology, heat treatment technology and collaborative disposal technology, etc. The advantages and disadvantages of these technologies were comprehensively analyzed. Moreover, based on the existing pain points of fly ash disposal, a new idea of multi-technology combination was put forward, including two processes: one-step solution of main problems, supported by multiple methods, and sequential multi-step solution of problems. At last, suggestions and prospects for harmless disposal and recycling of fly ash were provided.