pH值对强化混凝去除水中微量有机物的影响

通过烧杯试验,分别以聚合氯化铝(PAC)和FeCl3为混凝剂研究了pH值对水中有机物去除的影响。研究结果表明:PAC的最佳投加量为8 mg/L,此时有机物和浊度的去除率分别为51.8%和93.6%;FeCl3的最佳投加量为50 mg/L,此时有机物和浊度的去除率分别为57.8%和95.0%。有机物去除的最佳pH值范围为5.5～6.5,浊度去除的最佳pH值范围为7～8;相对于原水而言,调节pH值能够使有机物的去除率提高10%左右,因此调节pH值是一种经济有效的去除水中有机物的强化混凝方法。

Effect of pH value on removal of trace organic compounds in water by enhanced coagulation process

Using polymeric aluminum chloride(PAC) and FeCl3 as coagulants,the effect of pH value on the removal of organic compounds in water was studied through the jar test.The results showed that,the optimal dosage of PAC was 8 mg/L,the removal rates of organic compounds and turbidity were 51.8% and 93.6% respectively at the concentration;for FeCl3,the optimal dosage was 50 mg/L and the removal rates of organic compolunds and turbidity were 57.8% and 95.0% respectively.The optimal pH value was in the range of 5.5-6.5 for the removal of organic compounds and 7-8 for the removal of turbidity.In view of the raw water,the removal rate of organic compounds could be improved by 10% through adjusting pH value;therefore,pH adjustment could be an economical and effective measure of enhanced coagulation for the removal of organic compounds in water.