饮用水中的磷及其在常规处理工艺中的去除

Phosphorus in drinking water and it's removal in conventional treatment process

对某市某水厂水源水和出厂水中磷的存在形式、常规处理工艺对总磷 (TP)和微生物可利用磷 (MAP)的去除进行了研究 .结果表明 :①水源水中的磷主要以非溶解性形式存在 ,溶解性总磷酸盐约占总磷 30 % ;溶解性正磷酸盐只在个别月份检出 ,且浓度很低 ;②水源水中微生物可利用磷浓度一般高于溶解性总磷酸盐浓度 ,说明微生物也可以利用非溶解性磷 ;③出厂水中溶解性总磷酸盐占总磷的比例较水源水中溶解性总磷酸盐占总磷的比例升高 ,说明其去除较非溶解性的磷困难 ;④常规处理工艺对总磷和微生物可利用磷去除效果较好 ,平均去除率分别为 6 6 %和 6 9% ,混凝沉淀单元和过滤单元对总磷去除效果均较好 .强化混凝工艺 ,降低出厂水中的MAP 。

Chemical forms of phosphorus in source and treated drinking water were studied in this paper. Removal of total phosphorus (TP) and microbially available phosphorus (MAP) by conventional treatment process of drinking water was examined. The results showed that particulate phosphorus constituted of most TP in source water. Content of total soluble phosphate (TSP) was about 30% of TP. Soluble reactive phosphate (SRP) can be measured in a few months during a year and its content was very low. Content of MAP was higher than content of TSP in source water, which showed that microbe can also use particle phosphorus. Ratio of TSP to TP increased evidently in treated water. This demonstrated that removal of TSP was more difficult than particulate phosphorus in conventional treatment process for drinking water. Removal of TP and MAP in conventional treatment process of drinking water was effective, with averaged removal efficiency of 66% and 69%, respectively. Coagulation-sedimentation and filtration removed TP efficiently. Enhanced coagulation may increases removal efficiency of MAP. Lower content of MAP can control biostability of drinking water.