The function of water purifying agent in papermaking wastewater
TIME:2023-07-21 17:32:47SOURCE:admin
Water purifying agent has the following functions in papermaking wastewater.
1.Papermaking white water recovery: the waste water from the press is called papermaking white water. It is rich in fiber, inorganic filler and various chemical additives added in the pulp. Generally speaking, inorganic flocculant (polyaluminum chloride), anionic flocculant or cationic flocculant (cationic polyacrylamide CPAM) are used in the recovery of white water, and cationic (air flotation treatment) is usually used.
2.Pulping additives: at present, the retention and drainage aids are mainly polyacrylamide and starch modified products. Polyacrylamide is mostly imported cationic products, with powder and emulsion. At present, the powder polyacrylamide occupies the main market, and its biggest advantages are low transportation cost and high dosage. The disadvantage is that it should be dissolved with water before use.
3. Pulping wastewater treatment: the wastewater from pulping and papermaking process is generally divided into pulping wastewater, kraft pulp wastewater and semi chemical paper wastewater; the main pollutants are: ① suspended solids: mainly fiber and fiber fines; ② easily biodegradable organic matter: mainly low molecular weight hemicellulose, methanol, acetic acid, sugar, etc.; ③ refractory organic matter: mainly fiber raw materials It contains lignin and macromolecular carbohydrate; ④Acid and alkali substances.