Study On Treatment Technology Of Xiaojianxi Leachate Extension Project

Along with the development of urbanization,the number of urban residents continues to increase,while the level of people’s material life rises steadily,coupled with the orderly improvement of urban and rural garbage collection and transportation system,resulting in the continuous growth of domestic garbage in cities and surrounding towns,making the collection and disposal of urban garbage become a key content of urban management..At present,most cities,such as Beijing,Shenzhen,Hefei,Changsha,Qingdao,Yangzhou and so on,use garbage collection trucks to collect the garbage centrally,then transport the garbage to the garbage transfer station,and finally transport the garbage to the landfill or incineration power plant of the garbage disposal site by large-scale garbage transport vehicles.The way of burning is treated.Landfill leachate is produced in the process of refuse collection,transit,landfill or incineration.Thus,landfill leachate treatment has become one of the important topics of garbage disposal.The Xiaojianxi domestic waste disposal Park was built in 2001,mainly undertaking the garbage disposal task in Qingdao.In the early stage of construction,the landfill site with 1500 tons disposal per day was used for landfill disposal.In 2007,a biochemical plant with 300 tons of garbage disposal per day was built in the park.In 2009,an incineration power plant with 1500 tons of garbage disposal per day was built(about 1800 t/d is actually disposed at present).Due to the increasing production of solid waste in Qingdao,the actual daily disposal capacity of the park is more than 4000 tons.Due to the rapid growth of domestic waste disposal in the park,the existing 700 m3/d leachate treatment facilities are difficult to meet the needs of the park,resulting in a serious backlog of leachate in the park,which requires further expansion of the park leachate treatment facilities.Based on the analysis of the quantity and quality of leachate produced in the first stage of landfill,the second stage of landfill and the first stage of incineration power plant,the future leachate production of Xiaojianxi domestic waste disposal park is predicted.The design scale of the reconstruction and expansion project is determined,and the process adopted for leachate treatment in China is analyzed.At the same time,the optimum process combination is determined in combination with the Xiaojianxi Leachate Phase I Project.The design schemes of leachate treatment units in Xiaojianxi Leachate Reconstruction and Extension Project are determined.The technological parameters of MBR+DTRO design section are studied,and the removal of pollutants and water volume transformation in each section are analyzed.To study the initial operation of the reconstruction and expansion project,analyze the test data and determine the operation control parameters.The completion of Xiaojianxi Leachate Revamping and Extension Project has made the final product of Leachate Disposal reusable standard water and landfill incinerated salt mud,thoroughly solved the problems of leachate accumulation in the park,high pressure of sewage treatment and difficult disposal of concentrated liquid,alleviated the pressure of garbage disposal in the park,and realized the recycling of resources in the park.It is expected that the centralized method will still be used in the collection and disposal of domestic waste for a considerable period of time in China.The pressure of disposal in various garbage dumps or incinerators is high.The leachate produced by centralized disposal of domestic waste is complex in composition and high in organic matter content,which requires reliable and stable leachate treatment methods.With the increasing demands of people on environmental quality,the treatment standard of leachate is also getting higher and higher.The Xiaojianxi Leachate Revamping and Extension Project adopts the process of anaerobic+MBR+DTRO to treat leachate.At the same time,the process of pretreatment+MVR evaporation+pickling+drying is used to treat concentrated liquor.The treatment standard has reached the surface water V standard and has achieved continuous and stable operation.The relevant experience can be used as a reference for the leachate treatment projects currently operating or constructing in China.