城市污水Al盐化学除磷的试验研究

针对新疆地区污水厂总磷去除效率有限,出水总磷存在超标排放风险的问题。试验中采用自配不同总磷含量的生活污水,通过小试试验,投加AlCl3进行试验室模拟化学除磷试验。研究结果表明:进水总磷浓度为2～4mg/L时,投加AlCl3/TP质量比为8.6;进水总磷浓度为6mg/L时,投加AlCl3/TP质量比上升到13.1,出水总磷浓度均<0.5mg/L,AlCl3投加不会改变污水的pH值,化学沉淀最佳时间为30min。建议设计除磷沉淀池的停留时间为25min～30min。

Study on Phosphorus Removal by Aluminum Salt in City Sewage

Some effluent concentrations of total phosphorus（TP） could not qualified the discharge standard because of the limited removal efficiency of TP in sewage treatment plants in Xinjiang.In this study,the simulation experiments on chemical phosphorus removal by AlCl3 had been carried out in the laboratory.The simulated domestic sewage with different TP concentrations was utilized.The results showed that when the influent concentration of TP was 2 ～ 4mg / L,the dosage mass ratio of AlCl3/TP was 8.6,which was up to 13.1 with an influent TP concentration of 6mg/L.When the effluent concentration of TP was under 0.5mg/L,the pH value of the treated water would not be changed by the dosage of AlCl3.The optimal sedimentation time for chemical precipitation was 30min.It＇s suggested that the residence time of phosphorus removal sedimentation tank was 25min～30min.