次氯酸钠有效氯的衰减特性与氯酸盐生成规律

Attenuation Characteristics of Available Chlorine and Chlorate Formation Rules of Sodium Hypochlorite

研究了水厂在夏冬两季及不同的环境储存温度下使用次氯酸钠,有效氯的衰减特性与氯酸盐生成规律。结果表明,次氯酸钠在夏冬两季使用过程中,有效氯呈现总体下降、氯酸盐呈现总体上升趋势。较高浓度的次氯酸钠中,有效氯下降率更高,氯酸盐生成量更大。而储存温度高于40℃且储存时间超过5 d时,有效氯的衰减才较为显著,温度对氯酸盐生成的影响更大,不同储存温度下氯酸盐的生成量差别明显,温度越高,氯酸盐的生成量越多。当储存温度低于33℃、使用周期在10 d以内时,出厂水中氯酸盐含量基本稳定在0.035 mg/L左右,次氯酸钠有效氯的降低和氯酸盐副产物的生成对出厂水水质的影响较小,尚不足以对饮水安全构成威胁。

Attenuation characteristics of available chlorine and chlorate formation rules by using sodium hypochlorite for water treatment plants(WTP)in summer and winter as well as under different environmental storage temperatures were studied.Results showed that an overall decrease in available chlorine concentration and an overall increase in chlorate concentration were observed both in summer and winter.Higher concentration of sodium hypochlorite had a higher reduction rate of available chlorine and more chlorate production.Attenuation of available chlorine was more significant when the temperature was higher than 40℃and the storage time exceeded 5 days,the temperature had a greater impact on the formation of chlorate.Amount of chlorate generated under different storage temperatures was significantly different and the higher temperature,the greater the amount of chlorate produced.When storage temperature was lower than 33℃and use period was within 10 days,the chlorate content in the factory water was basically stable at about 0.035 mg/L.Reduction of available chlorine and the formation of chlorate during the use of sodium hypochlorite had little impact on the quality of factory water,which was not enough to pose a threat to drinking water safety.