Research On Treatment Of Landfill Leachate By Combination Of Coagulating Sedimentation And The Biochemical Process Of Strengthened SBR

Landfill leachate is a kind of complex wastewater that contains many kinds of poisonous and damaging organic matter,which is usually a hard treatment.The quality of it is very bad because of it changes frequently.By now,there has not been a technology which is both economic and effective.To resolve the problem above,The experiment implies the technics of coagulation precipitate firstly,then treatment by biochemistry added sludge activated carbon is chosed.The analysis of treatment effects by many kinds of coagulation and mixture of three kinds of coagulation-flocculation has been considered.The landfill leachate having been precipitation is treated by Sequencing Batch Reactor(SBR) added sludge activated carbon.The method is optimized through adding different quality of sludge activated carbon and change the condition of treating.The condition of madding sludge activated carbon has improved.The main research results are as fellows:The mixture of three kinds of coagulation-flocculation of polymerization aluminum chloride(PAC),the polymerization iron sulfate(PFS) and the polyacrylamide(PAM) have been used to deal with landfill leachate.The comparatively treatment effect of the latter is much better than single coagulation-flocculation treating.The removing rate of COD_Cr is 68.2%and NH₃-N is about 20%.The landfill leachate of precipitation treating is treated by adding sludge activated carbon SBR.If the thickness of adding sludge activated carbon is 1.2 g/L,the volume loading is 0.5～1.5 kgBOD₅/(m3·d),the time of water is 1.0 h,aeration is 10.0 h,precipitate is 1.5 h,draining and idling is 1.5 h,the removing rate of COD_Cr is 85%and NH₃-N is 90%.The raw material of madding sludge activated carbon is compression sludge deprived from secondary sedimentation tank.The method is physical chemistry,the thickness of activating agent is 3 mol/L,the ratio of activating agent and drying sludge is 3:1,the aperture of sludge activated carbon is 24.2 nm,the pore volume is 7.1×10^-2 m³,the specific surface area is 436 m²/g, the yield is 37.2%,the iodine value is 385 mg/g,the methylene blue value is 390 mg/g.Comparing the common SBR,the adding sludge activated carbon SBR removing rate of COD_Cr raise 10%and NH₃-N raise 30%.Especially,the stability of adding sludge activated carbon SBR is better than the conmmon SBR,the effect of environment changing is less severe.The charge of treating a tonnage landfill leachate is 6.34 yuan,which is lower than any other methods.