According to the statistics of China's highway network, as of December 2015, the expressway opened to traffic nationwide was 125,000 kilometers, and it was equipped with a large number of high-speed service areas. Employees in the service areas would have a large amount of sewage, such as washing, car repairs, and public toilets. If the sewage is discharged directly without treatment, it will pollute the surrounding environment and seriously damage people's living environment. Taking effective measures to treat these sewages is of great significance for improving the living environment and ecological environment safety around the service area.
Since the highway is far from the city, the sewage produced by it is far away from the urban sewage collection pipe network, and a separate small-scale treatment facility is required to treat the sewage.
The septic tank of the highway service area is mainly used for simple treatment of sewage, but the treatment effect of the septic tank is not very satisfactory. The quality of the treated water is unstable and it is easy to cause groundwater pollution. According to the actual situation of sewage treatment in high-speed service area, the development of new sewage treatment equipment with simple operation, reasonable structure and low operating cost is of great significance for sewage treatment in highway service area.
The main polluting molecules of sewage in the highway service area are mainly floating matter, colloid, dissolved organic matter, grease and various germs. The sewage treatment equipment developed by Weijia Environmental Protection has shown strong practicability in the application of decentralized sewage source points in highway service areas. The sewage first passes through the grid to remove solid waste and grease. Separation of the suspended matter by precipitation. Sewage can remove macromolecule organic matter when passing through the anaerobic tank filler. The supernatant after the precipitation and separation is treated with hydrolytic acidification bacteria in a hydrolytic acidification tank to degrade the macromolecular organic compounds in the water into small molecular organic compounds. In the next aeration tank, the aerobic bacteria are adsorbed, absorbed, and oxidized to make it simple. Inorganic substances such as CO2, H2O, etc., have achieved the purpose of removing organic matter; at the same time, due to the metabolism of the biofilm, part of the aging film has fallen off to form suspended matter in the water. After the sedimentation tank, the particles are freely precipitated. The overflow enters the disinfection tank, and the purpose of disinfection is achieved by adding sodium hypochlorite, so that the sewage treatment can be discharged. All indicators of sewage treated by Weijia Environmental Protection Sewage Treatment Equipment can meet the national level 2 or higher discharge standards.
With the gradual increase of people's awareness of environmental protection, the state's efforts to treat sewage have been further strengthened. In addition, many service areas of domestic expressways do not have well-operated sewage treatment facilities. Weijia environmental protection sewage treatment equipment itself has many characteristics such as convenient installation, stable operation, and simple operation. It is suitable for decentralized sewage treatment such as expressways. It has practical and practical significance in the future sewage service application of highway service areas.