水中单宁酸对强化混凝除污染的影响研究

研究了水中单宁酸在聚合氯化铝做混凝剂时对常规混凝、高锰酸钾预氧化强化混凝以及预氯化强化混凝的影响。结果表明，常规混凝下单宁酸含量的增加对混凝除浊有一定的效果，随着单宁酸投加量从0增加到5mg／L，滤后水的浊度呈现下降趋势，最低可达0．56NTU，但对于有机物的去除影响不大。高锰酸钾预氧化条件下当单宁酸投量小于2mg／L时，增大单宁酸投量有助于浊度的去除，过多则不利于混凝。预氯化下增加单宁酸投加量有助于浊度的去除，但对出水UV25。影响不大；随着单宁酸投加量从0增加到5mg/L，出水的CODMn鼻隆低白谁如，

Effect of Tannic Acid of Water on Enhanced Coagulation

The study aimed at the effect of tannic acid on normal coagulation,preoxidation by potassium permanganate and prechlorination enhanced coagulation （EC）. The results showed that in the condition of normal coagulation, the increase of tannic acid was good for turbidity removal, and with the increase of tannic acid from 0 to 5 mg/L, turbidity of filtered water declined to 0.56 NTU, but the increase of tannic acid had no significant effect on organic matter removal. In the condition of preoxidation by potassium permanganate, more tannic acid was good for turbidity removal when it was less than 2 mg/L, but too much tannic acid was bad for coagulation. In the condition of prechlofination, more tannic acid was good for turbidity removal, but had no significant effect on UV2s4 ; with the increase of tannic acid from 0 to 5 mg/L, CODMn first declined, then rose.