Our country is a country with a shortage of water resources, urban water shortage problem is particularly prominent. Back flush filter the emergence of urban sewage is the effective and reasonable use. Back flush filter effluent is stable, low operating cost obtained people's consistent high praise.

　　According to statistics, there are 11 provinces (cities) of 103 urban water supply shortages at or above the county level, the serious water shortage city accounted for 56%. Many urban water production and living difficulties, urban water supply security is threatened. At the same time, because of the relative lag of cure of water pollution control and the contaminated water increases year by year, the shortage of water resources have been intensified.

　　Due to the water environmental pollution, much water in south China region has appeared the trend of water shortage, some cities face ShuiNan with dilemma. In the north, many cities plagued by resources shortage and water shortage. Water resources shortage and serious water pollution has become an important factor of restricting urban sustainable development, in some places water shortages even became the most important factors which restrict the development of the city.

　　Back flush filter using filter harmful substance in the water body effectively intercept, so as to achieve the purpose of purifying water, improve water quality. After back flush filter treatment of water quality is not only up to the national wastewater discharge standard, and after back flush filter treatment water repeatable, effective energy saving water recycling.

　　To sum up, in the back flush filter under the effective governance of urban sewage has been effectively solve. Now, back flush filter was vigorously promotion and application.