Working Principle of Coagulation Sedimentation Tank

The sedimentation tank for coagulation is an important component of the sewage treatment system, usually located in the primary treatment stage of the sewage treatment process. Its main function is to remove suspended solids, silt, organic matter, heavy metals and other pollutants in the water through the coagulation and sedimentation process, thereby improving the purification effect of water quality. In the sedimentation tank for coagulation, sewage undergoes a series of treatment steps, and the suspended and turbid substances in the sewage are transformed into sediment through physical and chemical methods to achieve the purpose of purifying water bodies. The working principle of the sedimentation tank for coagulation mainly includes the following aspects.

1. Coagulation. In the coagulation sedimentation tank, a certain concentration tank, a certain concentration of coagulant is added to the sewage, and the coagulant such as polyaluminum and polyiron. The main function of coagulant is to combine the suspended matter and muddy matter in sewage to form a large flocculant.

2. Flocculation. After the coagulant combines with the suspended substances in the sewage, many tiny flocs will be formed, and these flocs will aggregate with each other to form larger flocs. These larger flocs are better able to settle down, allowing for the separation of suspended substances from the sewage.

3. Precipitation. In the coagulation sedimentation tank, because the particulate matter in the sewage is large, it will sink to the bottom of the pool by itself under the action of gravity. At this time, the suspended substances in the sewage are deposited to the bottom of the pool, so that the upper water becomes clearer.

4. Clarification. After the first few stages of treatment, most of the suspended substances in the sewage have been precipitated, and at this time , the upper clear water can be further clarified. Under normal circumstances, the water body can be further separated by setting up inclined plates, partition plates, etc.

Coagulation sedimentation tank has a wide application prospect because of its simple and clear working principle and reasonable structure. In the future environmental protection and water resources management, the coagulation sedimentation tank will play a more important role in improving water quality and protecting the ecological environment.