Study On The Early Warning System For Xijiang River Source Water Quality Associated With Water Plant

With the deterioration of surface water quality and sustained occurrence of sudden water pollution, the raw water quality early warning system as the effective measures of water quality safety, has been applied and promoted in domestic and abroad. At present, the water quality safety warning is still in the initial stage in the lower reaches of the West River Basin. This paper taking 2014.02-2015.01 as a research cycle, to monitor and analyz the water quality of West River raw water and the whole water treatment process,studied the removal efficiency of pollutants under the conventional treatment process, and on this basis, proposed the early warning level of pollution index and early warning monitoring points according to the water quality of West River, and experiments were carried out to study the corresponding emergency measures of turbidity, ammonia, CODMn, to provide effective guidance and scientific regulation for the urban water supply security.The results showed that:(1) the water quality of the lower reaches of the West River was overall good, basically achieving the class Ⅱ of national surface quality standard(GB3838-2002). the main standard indicators were DO, CODMn, TN, ammonia nitrogen. algae content was high and the odor substances were occasionally detected. The reservoir quality was better than the West River,and TN,algae content was high. (2)According to the analysis of the seasonal and vertical changes of water quality index, the seasonal variation of water temperature, pH, conductivity, algae were obvious, and turbidity, CODMn, TP, algae were obvious stratification phenomenon, showing lower levels were higher. (3) According to the analysis of the correlation between water quality index, there were significant correlation between the organic matter, nitrogen, algae, odor and the conventional indicators(DO,pH,water temperature, turbidity, conductivity), and the nitrogen forms (ammonia nitrogen, nitrite nitrogen, nitrate nitrogen) conversion relationship were obvious, and obtained the regression equations of CODMn, TN, ammonia nitrogen, chlorophyll a,2-MIB.(4) The average removal rate of turbidity, TOC, UV254, CODMn, ammonia nitrogen, nitrite nitrogen, chlorophyll a were about 94.04%、21.34%、31.25%、33.9%、76.18%、88.21%、91.29% under the conventional process, but the chloride, TN, DOC and the odor substances were substantially free removal.(5) It was recommended that turbidity, pH, DO, conductivity, temperature, total nitrogen, CODMn, ammonia nitrogen, chlorophyll a could be used as the early warning indicators, and three sites including sluice outlet of pock rush, water intake pumping station, and the water plant inlet could be selected as the early warning monitoring points.