| The amount of municipal solid waste is increasing every year in china but the fly ash whose amount is equal to 3% of the MSW (municipal solid waste) has not been well treated so far. The MSWI fly ash that contains toxic heavy metals and dioxin is recognized as hazard waste and must be well treated. Thermal treatment has the advantages of good treating effect and reducing the amount of fly ash and it becomes a tendency of fly ash treating in the world.This study researched the migration characteristics of heavy metals during thermal treatment of MSWI fly ash. The muffle kiln was used in the small scale experiment of sintering, and the atomic-absorption spectrophotometer was used to determine the contents of heavy metals in the samples. This study investigated the migration characteristics of 6 heavy metals (Cd, Pb, Cu, Ni, Cr and Zn) in the sintering process of MSWI fly ash, and analyzed the influence of temperature, residence time, modeling pressure, additive and etc. onto the migration characteristics of heavy metals. The muffle kiln was also used in the experiment of calcining of MSWI fly ash. This study investigated the migration characteristics of 4 heavy metals (Cd, Cu, Cr and Zn) in the process of calcining and established vaporescence kinetics models of heavy metals. This study also deeply researched the technology of melting of MSWI fly ash, which is very popular in the world nowadays, and investigated the migration characteristics of 6 heavy metals (Cd, Pb, Cu, Ni, Cr and Zn) in the melting process of MSWI fly ash. At last, this study established pollution control evaluation models of heavy metals during the process of thermal treatment of MSWI fly ash, which was used in the experiment of sintering, and provided an effective way to the evaluation of stabilization effects of heavy metals during the thermal treatment of MSWI fly ash.
|
PDF Full Text Request