Application Of Membrane Bioreactor Combined With Low Pressure Nanofiltration Membrane In Advanced Treatment Of Wastewater

Water is the source of life and an indispensable resource for people's life and production.Advanced treatment and reuse of sewage is an important way to solve the problem of water shortage in China.In recent years,more and more membrane processes were used in the selection of wastewater treatment and recycling processes at home and abroad,It is not only efficient,low-cost,economical,but also has a removal rate of more than 97% for many pollutants.The result showed that Membrane Bioreactor combined with Low Pressure Nanofiltration Membrane is feasible for deep treatment and reuse of wastewater,and the reclaimed water discharge sewage will be upgraded to the Beijing Water Pollutant Comprehensive Emission Standard(DB11/307-2013) B standard;The high-quality reclaimed water will be upgraded to the surface class ? that meets the Surface Water Environmental Quality Standard(GB3838-2002).The main research results are as follows:(1)Renovation of Cuihu Reclaimed Water Plant by Membrane Bioreactor combined with Low Pressure Nanofiltration Process.Not increase the existing water plant land and the processing scale was expanded from 10,000m~3/d to 20,000m~3/d.and added 10,000 m~3/d high-quality reclaimed water,It capacity to achieve 7,000 m3 of high-quality reclaimed water per day.(2)By comparing of water quality through Membrane Bioreactor combined with Low-Pressure Nanofiltration Process to realizing the upgrade from low-end reclaimed water to high-quality reclaimed water,and treat the tail water of the sewage treatment plant in one step to meet the centralized drinking water quality index.In addition,Membrane Bioreactor effluent (including Low-Pressure Nanofiltration concentrated water) stabilizes to meet the Beijing Water Pollution Comprehensive Emission Standard(DB11/307-2013) B standard;The Low-Pressure Nanofiltration effluent stabilizes to meet the Class ? standard in the Surface Water and Water Environmental Quality Standard(GB3838-2002),and the overall pollutant removal rate can be stabilized above97%.7000 m~3 high quality reclaimed water will be used for industrial circulating make-up water,emergency water source and hydration of Cuihu Wetland.Building national water quality standards for wetland parks and promoting a good ecological system for the restoration of water environment in Cuihu Wetland.(3)By analyzing the total investment and operating cost of the Membrane Bioreactor combined with the Low Pressure Nanofiltration Process,Calculated that the total investment is lower than the traditional process,In addition,its core process low-pressure nanofiltration system has a water consumption of only 1kwh,the total processing cost is only 1.06 yuan/m3,which saves a lot compared with the traditional process.