Research on Combined Process of Coagulation,Sand Filtration,GAC and UF for Car Washing Wastewater Treatment

The combined process of coagulation, sedimentation, sand filtration, GAC and UF was applied for car washing wastewater treatment. The results show that this process has favorable treatment effect, and the effluent quality can reach the requirement for car washing wastewater reuse. The pretreatment including coagulation, sedimentation and sand filtration can effectively remove turbidity, LAS and NH3-N, considerably mitigate the load of subsequent advanced treatment processes and lessen the blockage of GAC and UF reactors. The removal rate of LAS by GAC is more than 70%, and the turbidity removal rate by UF is more than 90%. Using the combined process for car washing wastewater treatment and reuse can save 12 000 Yuan per year.