Study On The Variation Trend And Improvement Method Of Raw Water And Supply Water In Yangtze River Valley

Recently, with the rapid development of industry,farming manufacture and municipal construction, a large amount of domestic and pollutedindustrial sewage are poured into the Yangtze River. The major impact is that with the water level is elevated and water flow slows down, the Three George Dam is hampering the dilution process of pollutant, accordingly the shore pollution zone has been expanded.A gradually increased-severity trend in the organic pollution in the Yangtze River can be seen from upstream to downstream. The annually deterioration of the water quality of the Yangtze River can be clearly discoverd, which characterizes pollution mainly between Type II and Type III, excessive BOD5, NH3-N and phenol in a long period.as the standard of living and health consciousness increase, people are demanding a better drinking water quality. Current mandatory national standard, "Drinking Water Standards" promulgated in 1985, regulates Only 35 items, and includes conventional analysis focusing only on residual chlorine, turbidity, bacteria, E. coli these 4 indicators. From July 1, 2007, China will implement a new "drinking water health standards". At the same time, the old version of the standard will formally withdraw from the historical stage. And the new standard indicators have been increased to 106. The current drinking water deep treatment technology has made considerable progress. And a variety of economical and practical deep process technology is gradually becoming widely used. In recent years, deep processing technologies have been developed both domestically and internationally. And they can be divided into enhanced "Coagulation - sedimentation - filtration" technology, adsorption technology, oxidation technology, photochemical processing technology, biological pre-treatment technology, ion-exchange technology and membrane separation technology, etc.Through a large number of collection and analysis of all aspects of relevant information, as well as upstream and downstream of the Yangtze River field trips, this study summarized the Yangtze River's upstream and downstream water qualities of water sources, specifically analyzed the quality of municipal source waters from a chosen section in upstream from 2001 to 2008, and another section in downstream from 2005 to 2006, specially studied the effect of the Three Gorges Project on the Yangtze River source water quality, and analyzed the trend of the source water quality based on the above information acquired, and suggest some improvements.This study introduced several drinking water deep treatment technologies based on the pollution status and the changing requirement of the national water treatment. Through careful research on several representative waterworks along the Yangtze River, appropriate suggestions which is based on their current technical conditions have been made on the processes of these waterworks. Finally, this study concluded that improving traditional process and completing new technologies are the future developing trend and the guarantee of improving water quality.The results of this study provides basis for the development of water supplying business along the Yangtze River, serves as an important reference for follow-up study, conversion of old waterworks and implementation of new waterworks.