The basic methods of sewage treatment mainly include physical treatment and biochemical treatment.
Physical treatment is mainly through physical means, such as sedimentation, filtration, separation, etc., to remove large impurities, suspended solids, inorganic substances, etc. in sewage, so as to prepare for subsequent biochemical treatment. Common physical treatment methods include grid filtration, sedimentation tanks, filtration tanks, etc.
Biochemical treatment is to decompose and transform the organic matter in the sewage through the metabolism of microorganisms, so that the sewage can be purified. Biochemical treatment is generally divided into two ways: aerobic treatment and anaerobic treatment. Aerobic treatment is the use of aerobic bacteria to convert organic matter in sewage into harmless substances such as carbon dioxide and water under aerobic conditionsAnaerobic treatment uses anaerobic bacteria to convert organic matter in sewage into gases such as methane and carbon dioxide under anaerobic conditions.
The basic process of sewage treatment is as follows:
1.After the sewage enters the sewage treatment plant, it is first filtered through the grid to remove large impurities.
2.After being filtered by the grid, the effluent enters the sedimentation tank, where suspended solids and inorganic particles are removed by natural sedimentation.
3.After sedimentation tank treatment, the sewage enters the biological treatment unit, and aerobic treatment or anaerobic treatment is selected according to the specific situation.
4.After biochemical treatment, the wastewater needs to be subjected to secondary sedimentation to further remove suspended solids and organic matter.
5.Finally, after disinfection, the purified water that meets the discharge standards can be discharged directly into natural water bodies or as reused water.
Sewage