Sewage treatment which can be divided according to their role in accordance with its role in three sewage treatment can be divided into three physical, biological and chemical methods. ① physical method: The main advantage of the physical effects of the non-separation of dissolved substances in wastewater municipal sewage treatment works, the process does not change the chemical properties. Conventional gravity separation, centrifugal separation, reverse osmosis, flotation and the like. Treatment physical structure is relatively simple, economical, large towns and villages for water capacity, strong self-purification capacity, sewage treatment less demanding degree. ② biological method: the use of microbial metabolism, the sewage was dissolved or colloidal state of decomposition of organic matter is oxidized to stable inorganic substances, sewage purification. Commonly used activated sludge and biofilm. Biological treatment level is higher than the physical law. ③ chemical method: the role of chemical reactions to disposal or recycling of sewage colloidal substances dissolved substances or methods of sewage treatment works, and more for industrial wastewater. Commonly used coagulation method, neutralization, oxidation-reduction, ion exchange method. Treatment effects of chemical treatment, high costs, and more for the water after biochemical treatment, further treatment to improve water quality. Many people know the sewage is: turbid water is sewage. In fact, is not comprehensive, for sewage, GB has clearly defined. Xiao Bian today as we speak effluent standards under division. In GB, the drainage is divided into three criteria, namely GB one, two GB, GB three slaughter process sewage treatment works, GB one is divided into an A and a B, water emission standards around the provision may be different, and some require two, and some require three, of course, there are no provisions in force areas exist. China has not yet heard of the city as a standard provision of drainage, sewage treatment situation of Shanghai is the best city, is also only plan to existing sewage treatment plants all transformed into a B standard. Water sewage treatment is how to divide it, there are five general inspection standards, COD, BOD, SS, NH3-N, TP, COD: Chemical oxygen demand BOD: Biochemical Oxygen Demand SS: suspended particles NH3-N: ammonia Content TP: phosphorus content of an A --COD: 50 Shanxi sewage treatment works, BOD: 10, SS: 10 a B - COD: 60, BOD: 20, SS: 20 two --COD: 100, BOD : 30, SS: 30 three --COD: 120, BOD: 60, SS: 50 Shanxi sewage treatment works, sewage treatment works, environmental protection provided by the Run-Run-Environmental Engineering Co., Ltd., Shanxi. "Sewage treatment, waste gas treatment, dust processing the" preferred Runtong Shanxi Environmental Protection Engineering Co. (2), the company is located at: Taiyuan, Changzhi Road Man Wah Area C, over the years, Runtong environmental protection to provide customers the best quality service Contact: on behalf of the manager. Welcome to the new and old customers call, letter, visit the guide, business negotiations. Run-green look forward to be your long-term partner!