| Municipal Solid Waste (MSW) has increased rapidly with the development of economic and the improvement of living standards. And meanwhile MSW composition has also changed. The composition of plastics and textiles are increasing every year. The component of food residue is about 50%. The organic component and the thermal value are increasing evidently. Having the advantages of remarkable Volume-reduction, weight-reduction and energy-recovery, disposal of MSW by incineration is being popularized worldwide in resident years.Because the component of MSW is very complex, heavy metals and organic combustion by-produces may be generated during MSW incineration. And if the combustion by-produces were not managed properly, it might cause secondary pollution, and MSW incineration fly ash is usually defined as hazardous waste. In order to realized non-hazardous' treatment technology of MSW incineration. To understand the generation mechanism and control technology is very important during MSW non-hazardous treatment. The transfer mechanism of heavy metals during MSW incineration and leaching characteristic of heavy metals in MSW fly ash were investigated in this thesis. In addition the possible application of MSW fly ash was discussed. And it established bases on reducing the toxicity of heavy metals in MSW incineration.The effects of temperature, chlorine and water on the partitioning of heavy metals were studied using a laboratory fluid bed furnace on the basis of heavy metals content analysis of the mean physical compositions of MSW. The experiment results showed that temperature and chloride content in the feed had significant influence on the volatile of heavy metals, and the influence of water was slight. The results also indicated the initial metal concentration in the feed was not a significant parameter affecting characteristics during incineration.The physical and heavy metals content were researched of fly ashes from different type ofMSW incinerator--pure MSW grate incinerator and MSW-coal CFB incinerator. The resultsindicated the content of heavy metals in fly ash from grate incinerator was higher than that of CFB incinerator, and the leaching amount of heavy metals in fly ash from grate incinerator was also higher than that of CFB incinerator. Heavy metals content in fly ashes increased with size decreasing of fly ashes. The leaching characteristic of Cr, Cd, Cu, Zn slight increased as size decreasing of fly ashes. And other heavy metals hadn't clear relationship with the size of fly ashes. The content of Zn and Pb were the highest and the content of Cd was very lower. And the leachingrate of Cd was very higher.The experiment results showed that the leaching rate of heavy metals of cement stabiliazation of MSW fly ashes were very lower, especially for Cd, Pb, Zn. From the point of using waste to treat waste, FCA (fluidized bed combustion coal fly ash) as a MSW fly ash stabilizer could reduce the leachate concentrations of heavy metals, and the multiple use of FCA and cement resulted in effective containment of heavy metals.The evaporation properties of heavy metals were studied use tube furnace. The result indicated the evaporation of heavy metals was very high around 900 C. And meanwhile the influence of CaCl2 on heavy metals' evaporation was studied. The result shown the evaporation for Pb, Cu, Zn and Cd were as high as above 90% when some chlorination agent was added. The toxicity of fly ash was markedly decreased.Neural network models, to predict the acid neutralization capacity and the leaching characteristic of heavy metals of mixture of cement and MSW fly ash were constructed. The construction of the two models were 13X7X1, 9X12X4 respectively. The work has shown that development of good empirical predictive models for solidified product leachate pH and heavy metals leaching were feasible. This work provided a convenient instruction for the solidification/stabilization of MSW fly ash.
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