Study Of Sewage Sludge Of Chong Qing Used As Daily Cover Material In MSW Landfill

Along with development of drainage project and synchronous increase of drainage quantitative and treat efficiency, Currently, the output of sewage sludge has been increased . However, eventual disposal of sewage sludge has not been settled. Sewage sludge effectivly disposedl,especially sewage sludge reused has become a urgent problem.The paper elaborated the problem of sewage sludge and the main disposal technologies in China ,especially in ChongQing. It pointed out the necessity and possibility that sludge could be used as daily cover materials in MSW landfill and builded research techno-way that sewage sludge modified used as daily cover materials for MSW landfill. It also reviewed the research advances and affecting factors that sludge modified used as daily cover materials for MSW landfill at home and abroad.Bei bei sewage treatment plant'un-digested sludge anda Tang jia qiao sewage treatment plant'digested sludge were used as research subjects in laboratory research in this paper.The results show that fresh un-digested sludge and digested sludge will bring a great influence for landfill manipulation and increase the output of landfill leachate as moisture content is high. Fresh sewage sludge is not suit for daily cover materials in MSW landfill and it must be modified.The experiment of sluge modified adopted additives which were desiccarion, calcium oxide and refuse burning ash. Sewage sluge blend with additive or sludge blend with different ratios of additives in order to meet the requirements for landfilling. The permeability coefficient of different mixed samples was also measured using simulate rain experiment .The character of the leachate produced from mixed samples was studied in order to find our factors that sewage sludge modified used as daily cover materials may bring forthe leachate of landfill.The experiment which the sludge drying used as daily cover materials shows that the moisture content of samples has been reduced effectivly,but the effect for the organic matter content is not obvious. The permeability coefficient of drying sludge has relation with moisture content. The antiseepage of drying sludge is not good as soil, it will increase water quantity of laystall in rainy season,the leachate produced from the drying sludge has a higher concentration of CODcr,which will increase contaminated load of MSW landfill. Using calcium oxide and refuse burning ash as additives shows that the moisture content reduces as additives increases, the permeability coeficient of diferent mixed samples is improved, the moisture content may meet requirements of landfill, at same time the leachate produced from the mixed sample will not bring pollution. Sludge modified using calcium oxide and refuse burning ash as additives can be used as daily cover materials for the landfill. The integrated effect of refuse burning ash as additives is better than calcium oxide as additive because this way can achieved the disposition of refuse burning ash.The creative point of this paper is that it is first time using refuse burning ash as additive mixed with sludge for daily cover materials for the landfill. It provides the new way for comprehensive exploitation of refuse burning ash and sludge , saves the soil resources at the same time.The unification of the resources, environment, benefit could be acheieved, the purpose of waste treated by waste was attained.