Optimization Of Design For The Landfill Leachate Treatment Scheme In Lanzhou New District

As China’s fifth new National District, the new district of Lanzhou, will become an important growth stage in the western region. It is necessary to construct the basic sanitation facilities to match the needs of development. The landfill is located in new district in Lanzhou Wang Jiagou, about20km southeast of water-qin highway on the eastern side; Its daily average is520t/d, its service life is14years, the total amount of garbage treatment is2,650,000t and storage capacity is3,900,000m3; leachate treatment plant daily processing scale is120m3. New municipal solid waste landfill project has completed the preliminary design. Through on-the-spot investigation and research, the design of the landfill leachate treatment scheme has some flaws, about the reservoir engineering, flood control project and the leachate treatment scheme.It is well known that leachate treatment is one of the most important design of landfill, so this paper focus on choosing the most appropriate way to treat leachate. By comparing the original scheme which use two MBR+STRO technology with optimization method which use recirculation technology. Specifically, it analyse process principle, technological process, post-operation, the complexity of operation, economy and other aspects. Finally, recirculation technology should be adopted, because it is more scientific and more practical.According to our latest technology policy of leachate pollution control, we should follow "combine of source reduction, process control and treatment control, combine of technical measures and management measures, combine of practicability and economy" Consider weather characteristics and the specific situation of the landfill, leachate reduction control measures include:set a diversion dam, design5anchor platforms, set up drains on the platforms, the top anchor platforms cater to floodwater catching channel, Therefore, achieve the purpose of partition the landfill, separate rain and leachate, reducing leachate from the source. On this basis, combine the design of landfill, using the empirical formula method to calculate quantity of leachate, determine the yield of wastewater flows, design leachate recirculation cell and recirculation distribution system, then complete the design.In this paper, using recirculation to treat leachate of Lanzhou new district landfill is not only control the leachate contamination of the environment at the most extent, reduce leachate day capacity to60m3/d, but also greatly reduce the investment and space. New leachate treatment engineering embodies the combination of practicability and economy, has obvious social benefit, environmental benefit and economic benefit.