Generally, polyacrylamide is used as a flocculant, including sedimentation, clarification, concentration and sludge dewatering processes. It is also widely used in industries. According to the source of sewage, it is mainly divided into two types: urban sewage and industrial wastewater.

    Urban sewage: refers to the collective name of sewage discharged into the urban sewage system. At the same time, urban sewage also includes domestic sewage and industrial sewage. When polyacrylamide is used as a flocculant for urban sewage, cationic polyacrylamide is generally used, and the ion degree is average. It is about 40%~60%. Of course, depending on the water quality, specific problems have to be analyzed in detail.

    Industrial wastewater: if classified according to the chemical properties of the main pollutants contained in industrial wastewater, it is mainly divided into: organic wastewater containing mainly organic pollutants, inorganic wastewater containing mainly inorganic pollutants, and organic and Mixed wastewater of inorganic substances, wastewater containing radioactive substances and cooling water polluted only by heat, and heavy metal wastewater. For example: wastewater from food or petroleum processing is organic wastewater, while wastewater from mineral processing and electroplating wastewater are inorganic wastewater. According to the classification of industrial processing objects, polyacrylamide can be divided into: metallurgical wastewater, textile wastewater, papermaking wastewater, tannery wastewater, pesticide wastewater, oil refining wastewater, mineral processing industry, dyeing industry and sugar industry, etc.

    Municipal sewage and industrial sewage are often treated with activated sludge. Activated sludge is often a highly hydrophilic colloid with high organic content and is extremely difficult to dehydrate. Treated with cationic polyacrylamide, less dosage, high dehydration efficiency, easy to separate.

    Alcohol factory wastewater, brewery wastewater, monosodium glutamate factory wastewater, sugar factory wastewater, meat factory wastewater, beverage factory wastewater, textile printing and dyeing factory wastewater, etc. use cationic polyacrylamide than anionic polyacrylamide, nonionic polyacrylamide Or the effect of inorganic salts is several times or tens of times higher. Because this type of wastewater generally has a negative charge.