| Along with China's urbanization and the faster pace of city's rapid economic development, urban garbage problem is becoming increasingly prominent. Ecology health landfill of domestic garbage is a main method in processing the town garbage in our country at present and even on a long period of times. A large quantity of leachate can be produced in the degradation of the garbage in landfill, the density of BOD5, CODCr and NH3-N of leachate is very high , which can easily pollute the surface water and ground water environment seriously. The leachate of Landfill contains a variety of pollutants such as organic matter, ammonia, heavy metals, which are high in concentration and often changed by time, weather etc. These lead to the difficulty in treating landfill leachate at home and abroad.Based on the systematic analysis of the forming processes of the leachate, the water characteristics, the component and its treatment methods at home and abroad, the study researched the leachate of the Er fei Shan landfill in Wuhan city. This paper put forward "air stripping + UASB" techniques to treat the leachate.The high concentration of ammonia is a notable feature of landfill leachate. It can Create the suppression to the following biochemistry processing. Therefore the direct use of conventional biological treatment to high concentrated ammonia wastewater is very difficult. At first, air stripping as the pretreatment is carried on for landfill leachate. By adding the lime to adjust the pH of the leachate, and taking the pH, the temperature, the stripping time as the parameters to conduct a series of experimental study, it obtained the proper stripping treatment proess design parameters. The results showed that stripping results were better when the water temperature is 20℃above, pH was 10.5 and stripping time was 8 hours. The efficiency of NH3-N stripping added up to 71.4%. What's more, the process could remove 14.5% COD, and pH fell down to 9.65 after a long time of stripping. The sewage biochemistry enhanced because the C/N ratio is bigger than 9 after the stripping. The inoculation sludge of UASB (Upflow Anaerobic Sludge Blanket) took from Wuhan sewage disposal plant. Some powdered activated charcoal with the size of 0.16-0.2 mm was added to the sludge. The parameters such as start-up period, organic loading rate, and organic removing rate in UASB reactor influence were explored in detail. The wastewater, which had been stripped off, was taken as inlet of UASB reactor. It operated great, and spate lamination appeared quickly. 62 days later, the maximum organic loading rate of the reactor came to 18.94kgCOD/ (m3.d) , the start-up period of UASB reactor could be shorten by 1/3.
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