采用"混凝—沉淀—超滤"和"混凝—超滤"2 种超滤膜快速处理工艺对初期雨水进行中试试验研究,试验结果表明超滤膜工艺对初期雨水中的CODCr、TP和SS等污染物具有较好的去除效果.同时超滤膜快速处理工艺用于处理污染雨水,具有占地小、启动快、可间歇运行、对初期雨水中污染物去除率高等综合优势,非常适合需要高效、快速治理污染雨水的项目.通过对超滤膜快速处理工艺不同参数设置研究发现,絮凝剂投加浓度存在明显拐点,当投加浓度超过拐点后,随着投加浓度的增加,污染物去除率并无明显增加;运行膜通量的高低对去除效果并无明显影响;"混凝—沉淀—超滤"工艺与短流程"混凝—超滤"工艺相比,对初期雨水中污染物浓度的去除效率相差不大.
Two ultrafiltration membrane rapid treatment processes,coagulation sedimentation ultrafiltration and coagulation ultrafiltration,were used to conduct pilot experiments on initial rainwater.The experimental results showed that the ultrafiltration membrane process had good removal effects on pollutants such as CODCr,TP,and SS in initial rainwater.At the same time,the ultrafiltration membrane rapid treatment process is used to treat polluted rainwater,which has comprehensive advantages such as small footprint,fast start-up,intermittent operation,and high removal rate of pollutants in initial rainwater.It is very suitable for projects that require efficient and rapid treatment of polluted rainwater.Through the study of different parameter settings in the rapid treatment process of ultrafiltration membranes,it was found that there is a significant turning point in the concentration of flocculants added.When the concentration exceeds the turning point,the pollutant removal rate does not increase significantly with the increase of added concentration.The high or low membrane flux during operation has no significant impact on the removal efficiency.Compared with the short process coagulation ultrafiltration process,the removal efficiency of pollutants in initial rainwater by the coagulation sedimentation ultrafiltration process is not significantly different.