中国六城市饮用水中氯化消毒副产物分布的研究

目的探讨饮用水中消毒副产物(DBPs)的分布及其分布规律,同时研究消毒副产物随季节变化及地带性分布规律。方法选取大庆、北京、天津、郑州、长沙和深圳6个城市,对其市政供水中水源、水处理等供水情况进行调查,同时对饮用水中主要消毒副产物三卤甲烷(THMs)及卤乙酸(HAAs)指标,以及天然有机物、pH、投氯量和水温进行监测。结果6个城市饮用水中三卤甲烷的范围为:未检出~92.8μg/L,卤乙酸范围:未检出~40.0μg/L。每种消毒副产物污染水平均在《生活饮用水卫生标准》GB5749-2006规定的限值范围内,但是其中2个水厂涉及3个末梢水三卤甲烷总量指标略高于标准限值。三卤甲烷分布为:郑州>天津>大庆>北京>深圳>长沙,其中郑州和天津2个地区水中三卤甲烷明显高于其他4个地区;卤乙酸的分布为:长沙>天津>深圳>大庆>郑州>北京,其中长沙、天津和深圳3个地区明显高于其他3个地区。此外,消毒副产物污染程度夏季明显高于冬季。结论目前中国饮用水中消毒副产物的分布处于较低水平;消毒副产物的产生呈明显的季节性,夏季最高;三卤甲烷主要分布在中国的北方地区,而卤乙酸主要分布在南方地区。

Study for distribution level of disinfection byproducts in drinking water from six cities in China

OBJECTIVE: To find the distribution level and geographical variations of disinfection by-products (DBPs) in drinking water. METHODS: The samples were selected from water utilities in six cities (Daqing, Beijing, Tianjin, Zhengzhou, Changsha and Shenzhen) of China. The water source and technology of water treatment were investigated and the indices including trihalomethanes (THMs) and haloacetic acids (HAAs) in main DBPs and natural organic materials (NOM), pH, chlorine dosage and temperature were determined. RESULTS: In six cities the highest concentrations of TTHMs and THAAs in the distribution system were 92.8 microg/L and 40.0 microg/L, respectively. The concentration of every compound of THMs and HAAs was under the limit of standards for drinking water quality, but the concentrations of 'TTHMs at some samples were higher than the maximum acceptable level (MAC) defined by standards for drinking water quality. The geographical variations of THMs and HAAs in six cities were Zhengzhou > Tianjin > Daqing > Beijing > Shenzhen > Changsha and Changsha > Tianjin > Shenzhen > Daqing > Zhengzhou > Beijing, respectively. The levels of THMs of drinking water at Tianjin and Zhengzhou were higher than the others and the levels of HAAs of drinking water at Changsha, Tianjin and Shenzhen were higher than the others. The seasonal variations of both groups of THMs and HAAs were high in summer and low in winter. CONCLUSION: The pollution level of DBPs in drinking water from Chinese six cities were low. The concentration of DBPs related to seasonal. THMs distributed mainly to the North and HAAs distributed mainly to the South.