预氧化剂投加方式对北江原水消毒副产物生成情况的影响

Effect of Adding Way of Pre-oxidant on The Formation of Disinfection By-products in Beijiang Raw Water

本试验通过改变预氧化剂的投加种类、投加方式、投加量、投加顺序,探讨其对北江原水消毒副产物前体物的去除情况影响,进而指导水厂生产实践。结果表明:三氯甲烷含量先随时间的增加有所上升,在20h左右升至最高,随后呈现下降趋势;预氧化效果优于预混凝效果,部分消毒副产物前体物在预氧化阶段反应比较充分;当二氧化氯投加量较低时,不能抑制三氯甲烷的生成,随着投加浓度的增加,对消毒副产物的去除效果得以提升;三氯甲烷生成潜能随腐殖酸浓度的增加而出现不同程度的增加;北江原水中三卤甲烷类消毒副产物前体物含量较低,投加过量次氯酸钠,反应较长时间,检测结果均低于国标限值。

In this experiment, the effects of pre-oxidants on the removal of precursors of disinfection by-products in Beijiang raw water were discussed by changing the type, method, dosage and order of pre-oxidants, so as to guide the production practice of water plants. The results showed that the content of trichloromethane increased with time, reached the highest at 20 h, and then decreased. The pre-oxidation effect was better than the pre-coagulation effect, and some disinfection by-product precursors had sufficient reaction in the pre-oxidation stage. When the dosage of chlorine dioxide was low, it could not inhibit the formation of trichloromethane. With the increase of dosage, the removal efficiency of disinfection by-products could be improved;the formation potential of trichloromethane increased with the increase of humic acid concentration. The content of disinfection by-products precursors of trihalomethanes in raw water of Beijiang river was low and excessive sodium hypochlorite was added and reacted with a long time, the detection results were all lower than the national standard limit.