In recent years, Taiwan's environmental awareness has risen and environmental issues have received increasing attention. The population in the metropolitan area is concentrated and the demand for car washing has increased significantly. The detergent used to wash the vehicle is discharged into the sewer systems with the wastewater from the car wash, causing a certain degree of pollution. The car wash can be roughly divided into mechanical car wash and manual or self-service car wash. And because the scale of car wash is relatively small, most of them do not have wastewater treatment facilities. Its maximum daily wastewater production can be slightly separated by 20 CMD. If the car wash wastewater is not properly treated, it will not only negatively affect urban appearance of the city, but also pollute the water quality. The current law stipulates that automatic car washing companies that produce more than 20 CMD of wastewater with automatic car washing equipment and need to apply for a discharge permit. The emerging car wash industry is currently small in scale and difficult to manage. Therefore, this project plans to develop wastewater treatment equipment to recover car wash wastewater generated by small and medium-sized car wash companies. It is hoped that the economic benefits of recycling will solve the problem of insufficient land, reduce the cost of wastewater treatment that small and medium-sized car wash companies can not manage. The project is to promote small and medium-sized car wash companies to use this technology to solve the current problems in the car wash industry. The combination of on-site test cyclo-flow filtration technology and electric coagulation flotation technology can treat car wash wastewater to meet the discharge water standard. Other necessary facilities, including raw wastewater collective ditch, water pumping and storage equipment have also been set up at the self-service car wash site. Four testing moduls that the two technologies are used alone or in series were verified, indicating the combined moduls obtained better results. The method of first electric coagulation flotation will produce slightly more sludge, but the lifetime of the filter material can be prolonged, and the quality of the treated water obtained is better; the method of first cyclo-flow filtration produce less sludge, while the water quality after treatment is slightly worse. However, the difference between two in-serial modules was not significant. The owner could adapt different modules based on the condition of the car wash factory.

electrocoagulation, car wash wastewater, filtration