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Investigation was performed to obtain an optimized process for the treatment of landfill leachate from Chongyang County municipal solid waste landfill.The various kinds of treatment processes of landfill leachate were summerized. These processes were classified into four categories which included physical-chemical method, biological method, AOTs and other methods. The removal substance, advantages and disadvantages, efficiency and the using situations of the basic treatment processes and combined treatment processes were summerized.The optimial process of Chongyang County landfill leachate was chosen by Analytical Hierarchy Process(AHP), based on anvanced, complexity, costs, social benefits , eco-efficiency and so on. The maximum weight of treatment process was option three.The complete treatment process of the option is: Landfill leachate→Adjusting tank→Coagulating sedimentation tank→Collecting tank→Deamination tower→IC tower→SFA/O tank→Secondary settling tank (UF)→Two level enhanced wetlands→Three level ecological purification system→Effluent. The option combines the technologies of physical, chemical, activated sludge, plant and soil systems. Its outstanding advantages is low cost, high social and ecological benefits. Primary treatment included Coagulating sedimentation tank and deamination tower, the main fuction is to remove SS. Secondary treatment method included IC tower, SFA/O tank and secondary settling tank (UF), primarily to remove high concentration of organic matters and residual ammonia. Tertiary treatment included ewo level enhanced wetlands and three level ecological purification systems, to remove the residual various types of pollutants.Calculation obtained the characteristica and size of each processs, and the expected treatment efficiency of BOD5, COD, ammonia nitrogen, SS were 99.2%, 98.9%, 97.3%, and 95.3%, respectively.
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