二氧化氯消毒饮用水中亚氯酸盐污染的初步研究

目的]了解二氧化氯消毒饮用水产生的亚氯酸盐（ClO2^-)污染现状，并探讨其成因和对策。方法]选择2个自来水厂，其中水厂以受轻度有机物污染的地面水为水源，乙水厂以未受有机物污染的地下水为水源，两个水厂均使用二氧化氯发生器，主要原料甲厂为亚氯酸盐，乙厂为氯酸盐。采用电流滴定仪法测定这2个水厂出厂水中ClO2^-浓度。结果]出厂水ClO2^-浓度：甲厂0．530－0．760mg/L，为标准值的2．6－3．8倍，超标率100％；乙厂0．100－0．733mg/L，其中超标浓度值范围0．257－0．733mg/L，为标准值的1．3－3．7倍，超标率83．3％。结论]甲、乙自来水厂出厂水中由二氧化氯消毒产生的消毒副产物亚氯酸盐污染较严重。

Priliminary Study on Chlorite Pollution of Drinking Water Disinfected by Chlorine Dioxide

Objective]To explore the status of chlorite pollution in drinking water due to chlorine dioxide ,as well as its causes and counter measures.Methods]A water plant collecting surface water as raw water slightly polluted by organic compounds and B water plant collecting ground water without organic compounds pollution were selected as observed objectives.Chlorine dioxide generators were used in both of A and B water plants,their raw materials was chlorite for A plant and chlorate for B plant.The levels of chlorite in treated water from these two water plants were determined by amperometric titration.Results]The levels of chlorite in treated water of A water plant ranged 0530~0760 mg/L, 26~38 times of the standard value,with a over standard rate of 100%,the levels of B water plant range 0257~0733 mg/L,13~3.7 times of the standard value ,with a over standard rate of 83.3%Conclusion]The treated water of A and B water plants presented higher pollution by chlorite,the by-product of chlorine dioxide disinfection