饮用水源中重金属镉去除的工艺技术试验

Technological Experiment of Cadmium Removal Processing for Raw Water from Drinking Water Source

以模拟受重金属镉污染的饮用源水为研究对象，观察了常规混凝沉淀技术、化学沉淀与常规混凝沉淀联用技术以及化学沉淀与强化混凝沉淀联用技术对镉污染源水的处理效果。结果表明常规混凝沉淀技术通过吸附作用对镉的去除率仅有62．8％-67．9％，难以达到国标要求；化学沉淀与常规混凝沉淀联用技术对镉的去除有较好的效果，但随着石灰投加量的增加会增加待滤水浊度，致使水体中吸附镉的悬浮胶体难以脱稳沉淀以及铝盐混凝剂存有解吸现象，导致镉的去除率下降；化学沉淀与强化混凝联用技术通过有效降低水体中含镉的悬浮胶体，很好地解决含镉污染高浊度源水的镉去除问题。

Taking the source water polluted by cadmium as research object, the removal effect of cadmium was investigated by conventional coagulation technique, chemical precipitation and conventional coagulation combined processes, chemical precipitation and enhanced coagulation combined processes. The results indicate that the removal rate of cadmium by the conventional coagulation technique is 62.89 % - 67.9 %, which is difficult to meet the national standard requirement. The removal effect of cadmium by chemical precipitation and conventional coagulation combined processes is good. But with the increase of lime dosage, water turbidity increases. Suspended solids adsorption of cadmium in water is hard to precipitate and coagulants exhibit desorption phenomena, causing cadmium removal rate decreased. By reducing suspension containing cadmium in water, chemical precipitation and enhanced coagulation combined processes is good at high turbidity raw water for cadmium removal.