The Comparative Research On Biological Treatment Of Small Town Wastewater

With economic development, water pollution is serious, deteriorating water quality. Since the 70's, Our country began to carry out the protection of water resources. However, with the development of economic construction, population growth, the development of small town enterprises is not only a substantial increase in water consumption and sewage is also a corresponding increase in emissions, the National Water Environment was the deterioration of the overall trend.At present, small town are faced with widespread pollution of water resources, environmental degradation trends, by 2010 the volume of urban sewage might have to increase to 30 billion. The level of small town as a result of the relative economic backwardness, lack of funds, lack of investment, if applied to simple and medium-sized cities in our country used the traditional sewage treatment technologies and processes, and its general infrastructure costs 1000～1200 yuan/(m3 ? d), to deal with the total cost of 0.60～0.70 yuan/m3, in many small town affected by economic constraints and can not afford. Therefore, the application of research and development of small town wastewater treatment in our country's economic and technology-based processing technology is imperative.In this paper, our country's small town for sewage treatment problems, the existing biological wastewater treatment process, from a technical and economic conditions are analyzed and compared to determine the small town sewage treatment process:(1) When the small town with a natural wetland or natural pond waste, wasteland, low-lying land, priority should be given the appropriate selection of artificial wetlands or stabilization pond law, save construction costs and reduce the use of arable land; dry region of small town can be stable Tong law; located in scenic resort, lakes, and Harbor areas of small town, to be used in SBR method, to ensure stable and reliable water quality, nutrition and the prevention of water body.(2) When the small town have a sewage treatment plant, but the need for the expansion and transformation, they can consider the A2/O method and the SBR method, two kinds of methods that can be in the original sewage treatment plant based on the transformation of the building.(3) When small town do not have the above-mentioned conditions, according to the local economy, technology, climate and other conditions, choose the right sewage treatment process, the proposed preferred oxidation ditch and SBR method, from a comparative analysis we can see that this two kinds of methods are suitable for small towns in general, integrated process than other methods conditions higher.