优化混凝沉淀减少残余铝的小试试验研究

Research on the Optimization of Coagulation Sedimentation to Reduce Residual Aluminum

针对饮用水中残余铝的问题,研究市场上低残余铝的混凝剂及助凝剂对控铝的效果。结果表明复合铝混凝剂控铝效果较差,低残铝聚硫氯化铝混凝剂有一定的控铝效果,在原水pH为9的情况下,沉后水残铝能控制在0.15 mg几以下,但对沉后水pH基本无调节作用,当原水pH>8.5时,沉后水pH就存在超标风险。此外,和聚硫氯化铝相比,硫酸铝引入助凝剂PAM后,有一定的提高除浊和控铝的效果。

In order to solve the problem of residual aluminum in drinking water, the effect of low residual aluminum coagulant and coagulant aid on aluminum control was studied. The results show that the composite aluminum coagulant is poor on controlling alu- minum. Low residual aluminum polysulfide aluminum chloride coagulant has certain effeet on controlling aluminum. When pH of raw water is 9, the precipitated water residual aluminum can be controlled below 0.15 mg/L. But when pH of raw water is over 8.5,there is excessive risk of pH in coagulation sedimentation effluent. In addition, compared with polyaluminium chloride, aluminum sulfate could improve the effect of removing turbidity and aluminum after introducing into coagulant aid PAM.