Research Of Shuangkou Solid Waste Sanitary Landfill Leachate Treatment Engineering In Tianjin

In recent years，with the development of national economy and the acceleration ofurbanization．China’s municipal domestic waste has been generating by around10%peryear growth rate which shows an increasing trend．As an inevitable product in the processof garbage harmless disposal, landfill leachate should be degraded effectively in time. Ifnot, there would be a tremendously potential pollution to ecological environment．Tianjin Shuangkou landfill site has run for nearly thirteen years，and whose landfillleachate belongs to medium leachate whose readily biodegradable component wasdecreased，but organic compounds of stable structure has been increased．Original“anaerobic+aerobic” combination of leachate treatment technology has been unable toreach the effluent index of landfill pollution control standard (GB16889-2008) issuedby Environmental Protection Department．At the same time，the mothod of dealing withthe landfill leachate of Shuangkou has already been listed by Tianjin municipalgovernment for building a state-level hygiene model city in2005．Consequently，in orderto reach the requirements of reexamination of building a model city and the new nationalstandards， the original process of Shuangkou landfill leachate treatment must beupgraded．The new process design ideas focus on improving the biochemistry of raw water and thebiodegradability carbon which is needed in decarburization．Consequently，the concept oftwo-level biochemistry has been brought．Firstly raw water enters the hydrolysis tank forhydrolysis and acidification which improves water quality biodegradability，Next，itenters the A/O nitrogen removal system．Due to the discrepancy of microbial populationand the limitations of backflow，the effluent of A/O should enter the secondary A/O poolfor denitrification in order to stabilize the total nitrogen requirements ofeffluent．Nitrification liquid enters through the solid-liquid separation membrane in MBRsystem for solid-liquid separation．Most particles and colloidal organic matter can betrapped by ultrafiltration system.Finally，the effluent achieved national sewage dischargestandard by NF and RO． After three months of debugging and operation， leachate through the process of“hydrolytic acidification+A/O/S+A/O+MBR+NF+RO” effluent conforms to thedischarge requirements of the landfill pollution control standard (GB16889-2008).