|其他摘要||The Economic Belt on the North Slope of the Tianshan Mountain is the most economic area of Xinjiang. However, due to frequent human activities, water pollution and organic pollution are increasingly worsening. Disinfection of drinking water is a key problem to be concerned. This study focused on surface water of important water sources on the Economic Belt on the Northern Slope of Xinjiang, with Guangdong Province as a comparison. Disinfection byproducts (DBPs) via chlorination or chloramination including trihalomethanes (THMs), haloacetic acids (HAAs), halogenated nitromethane (HNMs), haloacetonitriles (HANs) and haloketones (HKs) were determined. Statistical analyses were conducted using SPSS in order to investigate DBPs formation in the two disinfection processes and the above-mentioned environmental factors within confidence intervals. The results are listed below.
1 DOC and chlorination DBPs in Xinjiang and Guangdong waters are related to different environmental factors. In dry and summers in Xinjiang, DOC and chlorination DBPs have correlations with total phosphorus, total nitrogen and ammonia nitrogen. In summer, DOC is a significant contributor to TOC and UV254, but the contribution of neither UV254 to TOC nor chlorophyll to DOC or TOC is clear. In winter, UV254 contributes a lot to TOC, meanwhile chlorophyll has some contribution to UV254, which implies that DOC and DBPs are mainly related to nutritious elements in Xinjiang, especially in the summer of high temperature and more sunlight and rainfall and/or glacier melt water. Organic matters in water is generally eXogenous. Total phosphorus determines the quantity of algal organic matters, which cannot indicates the total organic matters in water in summer. Contrarily, it shows to a certain eXtend of indication when in winter the rainfall is eXtremely scarce. Aromatic organic matters is an important part of the total organic matters, which relates to ammonium or nitrate concentration level. In Guangdong water samples, DOC is related to chlorophyll amount, and chlorination total DBPs is also related to DOC and chlorophylls. This implies algae or water eutrophication has a great impact on DOC or DBPs formation that coincides with the weather and the developed industry in this area.
2 Results of comparing between dry and summers of Xinjiang showed that different disinfection methods could be adopted in water treatment in different seasons, due to sources and levels of DOC and the DBPs formation. In winter, chloramination could be applied, while chlorination in summer. In general, the two disinfection processes have no difference in the regression model of DBPs formation. DBPs formation has a significant relationship with organic matter level in the source water. For DBPs of the chlorination process in Xinjiang, the formation is more related to DOC in summer, while more related to UV254 in winter. Comparing Xinjiang and Guangdong, the DBPs formation via chlorination is more correlated to aromatic organic matters in Xinjiang, while in Guangdong significantly related to DOC for both disinfection methods.
3 The regression model built on significant level can work as an important reference for future water authorities to control the DBPs formation. For Xinjiang, the low eutrophication level of waters is beneficial. Although the pH levels of Xinjiang surface waters are generally as high as 8.5 to above 9.0, there is no significant effect of pH on DBPs formation as reflected in the regression model. The direct contributor of DBPs formation is the DOC level in water, therefore, artificial wastewater drainage needs to be controlled in order to decrease the organic matter level in waters.|