改良混凝条件对降低饮用水致突变性前体物的效果研究

A STUDY OF THE REMOVAL OF MUTATIONAL PRECURSORS IN DRINKING WATER BY IMPROVING COAGULATION CONDITION

以浊度、耗氧量(COD)和紫外线吸光度(UVA)为指标,用碱式氯化铝、聚合硫酸铁和三氯化铁等三种常用混凝剂对成都市自来水五厂原水进行了烧杯试验,以确定兼顾去除原水浊度和致突变性前体物的适宜pH和混凝剂投加量。研究结果表明:原水pH6～10是适宜pH范围,碱铝、聚合铁和三氯化铁的适宜投加量分别为3、15、5mg/L,通过成本—效益分析得知,碱铝是一种较为理想的混凝剂。

Alkali aluminum chloride, ferric chloride and polyferric sulfate wereused to jar test raw water samples from the Chengdu Fifth Water Plant tofind a suitable water pH and dosage of coagulant to simultaneously removeturbidity and mutational preeursors. The turbidity, chemical oxygen demandand ultraviolet radiation absorbance of the treated water samples were determined. Under the conditions of the study, the suitable water pH values ofthe coagulants were found to be 6-10, and the appropriate dosage of alkalialuminum chloride, ferric chloride or polyferric sulfate were found to be 3,15 and Smg/L respectively. The cost-benefit of the three coagulants was alsoanalysed, and the alkali aluminum chloride was found to be less expensiveand more effective than other two coagulants.