Comparative Study on Different Processes and Ultrafiltration for Surface Water Treatment

The combined process of ultrafiltration and coagulation-sedimentation and the combined process of ultrafiltration,sand filtration and coagulation-sedimentation were used to treat Luanhe River raw water.The treatment efficiency of the two combined processes was investigated,and the economic evaluation of ultrafiltration technology was performed to provide a reference for reconstruction of existing traditional waterworks.The results show that ultrafiltration has excellent treatment efficiency in the two combined processes.The removal rates of turbidity,total bacteria and total coliform are more than 90%,up to 100% and 100% respectively.The effluent quality from the combined process of ultrafiltration,sand filtration and coagulation-sedimentation is better and steadier than that from the combined process of ultrafiltration and coagulation-sedimentation.In addition,the operation cost of the combined process of ultrafiltration,coagulation-sedimentation and sand filtration is lower than that of the combined process of ultrafiltration and coagulation-sedimentation.It can be decided whether sand filter should be applied after comprehensive comparison in the reconstruction of waterworks.