Research On Influence Factors Of Chemical Stability Of Water In Drinking Water Supply Pipe Networks On Urban And Rural Areas

In recent years, as our country pays more attention on the development of rural areas, all regions have introduced policies to develop the urban and rural areas as a whole, and take the implementation of urban and rural integration as a development goal. Water quality issues are important support element of urban and rural regional development, and have a significant impact on production and life of residents. Existing study on the quality of the urban and rural areas mostly concentrates on the analysis of water quality indexes, but few focus on chemical stability of water in drinking water supply pipe networks. In order to ensure the standard of user's trap water quality, a research about chemical stability of water in drinking water supply pipe networks is looming ahead, which is important to improve network quality.This paper summarizes the research on chemical stability of water in drinking water supply pipe networks at home and abroad, and sets up pilot sites in Yancheng city, to research, and analysis status quo of chemical stability of water in this region. On this basis, to use a pilot test device of Water Quality Control Simulation newly built, and combined with the small scale experiments under different water conditions, the chemical stability of water quality status of water distribution systems. The main contents are as follows:(1) The survey for chemical stability of water in Yancheng drinking water supply pipe networks; (2) The iron release phenomenon in drinking water supply pipe networks; (3) Influence factors of chemical stability of water in drinking water supply pipe networks.In order to understand the chemical stability of water in Yancheng water distribution systems, this article conducts water quality investigation of water distribution systems in the area. According to the water supply coverage of Chengdong water plant and west water plant in Yancheng, select two waterworks factory water, and four-point chip area of water distribution systems as the research object of this paper, to analyze and summarize Yancheng Water Chemical stability condition. Investigation learned that water factory in Yancheng water pipe network of water has a certain corrosive, corrosive of water in summer and autumn is less than that in winter and spring, and each year about from August to October, water quality is less corrosive, it may also have fouling tendency. In addition, the area used for water pipe mostly cast iron pipe, some of the ions present in the water will destroy the pipe wall, causing corrosion of the wall and the release of iron, leading to "yellow water" and other water quality problems.To study the phenomenon of iron release in drinking water supply pipe networks, this article uses the single factor experiment method, study on pH, alkalinity, the initial concentration of chlorine, pipes, water pipes turbidity on iron release phenomena. Study found that the higher the pH, the greater alkalinity, increasing concentrations of chlorine, iron release will be relatively lower. For the old cast iron pipe and old galvanized steel pipe corrosion, as the reaction time, the release of iron will gradually increase. In the water, iron content increased, the turbidity will increase, so the iron pipe, turbidity can determine the iron content in the water is exceeded in a rough indicator. Using SPSS software for correlation analysis, to draw the order of factors affecting the iron release:turbidity>Cl->SO42->UV254 >alkalinity>chlorine concentration> pH.In order to study the factors of chemical stability in drinking water supply pipe networks, use of water quality control simulation test device, combined with the pilot plant to study the impact on the chemical stability of water, such as pH, alkalinity, chlorine initial concentration. pipe, flow rate. It found that by adjusting the pH and alkalinity, dosing disinfectant method can achieve the purpose of improving chemical stability of water. For the experiments several pipes, IL range is-1.00 to 0.20, the value of IR ranged between 7.30 to 8.60, as the reaction time will be, the value of IL is gradually increased, the value of IR decreased water quality corrosion waning. The chemical stability of steel pipe, UPVC pipe and PE pipe is better than cast iron pipe and galvanized steel pipe. At different flow rates, as the reaction time, the value of IL will gradually rise, the value of IR is gradually reduced, water corrosivity waning. When the flow rate ranges from 0.28 to 0.69 m/s, as the velocity increases, IL becomes more close to zero, IR is near to small, and the corrosion of water is weakend.