混凝沉淀法污水深度处理条件优化

Optimization of Conditions for Advanced Wastewater Treatment with Coagulation and Sedimentation Processes

采用混凝沉淀法处理二沉池出水,进一步去除水样中的有机物、磷和细菌。通过投加消石灰、聚合氯化铝(PAC)、三氯化铁等试剂,分析了pH值、总磷(TP)、化学需氧量(COD)和细菌指标,找到最佳的处理试剂及其投加量。结果表明:单独投加消石灰的最佳投加量为500 mg/L,综合考虑处理效果和经济因素投加量为500 mg/L的消石灰与15 mg/L的三氯化铁联合投加为最佳。经过处理出水水质达到了景观环境用水水质(GB/T 18921—2002)的标准。

Secondary sedimentation tank effluent was treated by flocculation,which could remove organics,phosphorus and bacteria further from wastewater.pH,total phosphorus（TP）,COD and bacterial index were analyzed through addition of hydrated lime,polyaluminum chloride and FeCl3,and optimum reagent and dosage were researched.The results indicate the optimum dosage only with hydrated lime is 500 mg/L.Considering treatment effect and cost,combination addition of 500 mg/L hydrated lime and 15 mg/L FeCl3 is optimum,which makes effluent quality meet the water standard of landscape environment（GB/T 1981—2002）.