Study On The Method Of Two-level Nitrification-Denitrification And Ultrafiltration To Deal With Ammonia Nitrogen Of The Waste Leachate

With the development of urbanization in our country,quantity of waste produced from city life has increasing with each passing day.As the waste disposal filling become the predominant way of municipal refuse disposal at the present stage, the number of waste disposal filling site is increasing with years.Waste Leachate is the inevitable outcome in the course of operation of waste disposal filling site.As our nation is increasing of waste leachate effluent standard,how to carry out effective disposal of waste leachate water, especially waste leachate ammonia nitrogen removal,in order to prevent surrounding groundwater,soil and life- form,etc from coursing serious pollution has become an important issue that needs immediate resolution.The thesis first introduced the physical method,chemical method and biological method in the treatment of waste leachate,the application of ammonia nitrogen.O n the basis of comprehensive analysis and comparison of each process,put forward using the “two levels of nitrification and denitrification + ultrafitration process to remove ammonia nitrogen in waste leachate,thesis this technology was applied to practical engineering,for some county in shanxi guanzhong landfill leachate treatment process parameters were determined.The thesis studied the two levels of nitrification- denitrification + ultrafiltration process of removing the ammonia nitrogen in landfill leachate of various factors, and to determine the appropriate scope of various factors.Its scope is:①Temperature should be between 20℃~30℃;②pH should be between 7.5~8.5;③DO not less than 2.0 mg/L, general is 2.0~3.0 mg/L;④The C/N ratio should be between 5~7;⑤Reflux ratio should not be commonly less than 200%;⑥Hydraulic retention time generally take 12h~3d, the older leachate, up to 20d;⑦All landowners ultrafiltration velocity of 4m/s, operating pressure is 0.8Mpa.The thesis using the method of dynamics of "two levels of nitrification-denitrification + ultrafiltration process of structure size and ultra filtration operation parameters are determined.Structure size parametres:The first level nitrification – denitrification,the total volume of 1136.7m3,including first level of nitrifying pool volume of 909.36m3,first level of denitrifying pool volume of 227.34m3;The second level nitrification – denitrification,the total volume of 197.9m3,including second level of nitrifying pool volume of 158.32m3,second level of denitrifying pool volume of 39.6m3.Ultrafiltration membrane system running parameters:The membrane flux for 65L/h·m2, Single area of ultrafiltration membrane for 15m2,Water sludge concentration for 15kg/m3, Cleaning flow for 60m3/h.The length of the membrane module for 3000 mm, components outside diameter for 160 mm.