氯气灭活饮用水中隐孢子虫的影响因素

应用荧光活体染色法研究Cl2在水体中杀灭隐孢子虫的效果,并探讨投加量、作用时间、浑浊度、pH值、温度、有机物含量等对Cl2灭活隐孢子虫效果的影响规律,找出最佳投加量和作用时间.结果显示,隐孢子虫浓度1×106个/mL,温度22℃,pH7.0,浊度为1.0NTU,氯气投加量大于6.3mg/L,反应时间360min,隐孢子虫的灭活率可以达到预期灭活效果(灭活率﹥99.0%).隐孢子虫的灭活率与氯气投加量和作用时间成正相关;灭活率随着浑浊度增加逐渐下降,浑浊度0.1~20.0NTU范围内,氯气投加量为6.3mg/L,作用时间大于900min,即可保证隐孢子虫的灭活率符合预定要求;在弱酸性条件下氯气灭活隐孢子虫能力强于碱性条件,反应温度(5.0~35.0℃)范围内,隐孢子虫的灭活率与温度成正相关;HA浓度0~10.0mg/L,作用时间为360min时,灭活率随有机物浓度增加而降低.当作用时间为900min时,水中隐孢子虫的灭活率均大于99.0%.

Effect of various factors on chlorine inactivating Cryptosporidium in water

In order to study the effect of Cl2 inactivating Cryptosporidium in water, different factors as Cl2 concentration, contact time, pH, temperature, turbidity and organic content which might influence the inactivation were studied by using fluorescence staining method. With the Cryptosporidium concentration was 1×106/mL, turbidity 1.0NTU, temperature 22℃, pH 7.0, and after 360 min reaction, under the condition that the Cl2 concentrations was 6.3mg/L, the inactivation ratio could be more than 99%. The lower turbidity was, the higher inactivating ratio could be received. If the inactivating time achieved 900min, it could meet the presetting inactivation ratio with turbidity 0.1~20.0 NTU. The ability of Cl2 inactivating Cryptosporidium was stronger under acidic condition than that in alkali circumstance. With the increasing temperature, the inactivating effect was increased. When the reaction system contained different concentration of organics(0~10.0 mg/L) and the inactivating time 360min, the inactivation ratio reduced with concentration increasing. Besides, when the inactivating time achieved 900min, the inactivation ratio could achieve 99%.