There are more types of cesspools, according to the place can be divided into indoor, semi-open-air and open-air, according to the type of sewage: electroplating and circuit board type production enterprise sewage, printing and dyeing and other enterprises of sewage, sewage and other types of sewage life. In the face of various types of sewage, sewage treatment methods are more diverse. Coagulation and precipitation method is the use of coagulants to purify industrial wastewater treatment method, can be used to deal with drinking water, industrial water, domestic water quality treatment.

Foam generation and sewage organic pollutants and surface-active substances related to the surface-active substances on the polar groups selectively adsorbed by the hydrophilic substances, converted into hydrophobic substances and adhered to the bubble water film, resulting in bubbles; due to the mixing operation of sewage treatment equipment has led to a large number of air involved in the sewage, resulting in the combination of gas-liquid combination of the two, resulting in bubbles; In addition, the sewage microorganisms in anomalous In addition, the microorganisms in the sewage abnormal reproduction, and contains lipids, resulting in an increase in the surface tension of the water body, the bubble is not easy to rupture.