Study On Physicochemical Technology And Its Mechanism For Treating The Leachate From MSW Incineration Cite

Nowadays, incineration and power generation is popular way in municipal solid waste (MSW) disposal in megapolis, which shows great advantage in pollutant minimization, resource ruse and detoxification of MSW and so on. However, it has to be mentioned that there also some problem would be coming to being during the process, for example dioxins produce, dust pollution, leachate from MSW dumpsite and so on. As a matter of fact, characteristics of leachate from incineration MSW dumpsite are quite different from that from landfill due to high organics contents, toxicity and biodegradability. There still have much refractory contaminant in the leachate after the biochemical treatment, which results in the fail of national discharge standards. As a result, post-treatment has to be used in this kind leachate control. It has to be presented that there are few study on the leachate from MSW incineration not only in China but also in developed countries. In order to effectively control this kind of new pollution, this thesis was studied and founded by national 863 (Hi-Tech Research and Development Program of China) and belongs to the program of "Municipapl solid waste incineration and pollution control". The leachate from biochemical treatments was used in Linjiang incineration plant of Wenzhou city and the combination process including coagulation and electrolysis (electro-fenton) were employed for advanced treatment in our experiments. Meanwhile, the technologies and mechanisms of physiochemical treatments were investigated in detail in this thesis.In order to screen out the efficient coagulant and appropriate unit to use coagulation process, eight kinds of coagulant such as polymer, inorganic salt, macromolecule coagulant aid and so on were used to treat the leachates effluent from biochemical treatment. As a result, polymeric aluminium and ferrous sulphate(PAFC), sulphate aluminium(AS), and cationic polyacrylamide(PAM) shows high efficiency in the coagulation than other kinds of coagulant. Moreover, to enhance the removal rate and save running cost, mixture coagulant were studied ulteriorly. It was shown that mixture coagulant had excellent pollutant removal effect in the leachate. For 1000mg/L of COD in leachate, with the dosage of aluminium sulphate polymericferrous and sulphate aluminium was 500mg/L and 200mg/L, the removal efficiency could be measure up to 40% of COD, 70% of color and 80% of turbidity in...