In our daily life, paper is being consumed in a large amount. And polyacrylamide is largely used in paper mills process of papermaking. Polyacrylamide in paper mill has good flocculation and can reduce frictional resistance between liquids. Polyacrylamide (PAM) in paper industry is widely used as retention agent, filter aid, homogenizer, and water treatment agent and so on. Its function is to improve the quality of paper, improve the pulp dehydration performance, improve the retention of fine fibers and fillers, and reduce the consumption of raw materials and environmental pollution.
Polyacrylamide could be used as paper dispersant, paper residence filter aid. The paper fibers and fillers in pulp are hydrophobic and tend to flocculate into clusters. It is difficult to produce paper with uniform properties and good strength. The addition of polyacrylamide promotes the dispersion of paper fibers and the formation of paper. Polyacrylamide flocculant is mainly used in pulping wastewater treatment and white water recovery. Other aspects are mainly used for pulping additives and their improvement of dry strength, wet strength and filler retention, thereby enhancing the flexibility of paper.
The main pollutants in pulping wastewater treatment are as follows: floats are mainly fiber and fiber fines; biodegradable organic compounds: hemicellulose, methanol, acetic acid, sugar, etc. with low molecular weight; refractory organic compounds: lignin and macromolecular carbohydrates mainly contained in fiber raw materials. At this time, the pulping wastewater is usually treated with inorganic flocculant aluminum sulfate and anionic polyacrylamide, and cationic polyacrylamide is usually used in the process of sludge thickening and dewatering.
Our flocculants could also be used in white water reuse: The effluent from the press section is called white water, which is rich in fiber, inorganic filler and various chemical additives added to the pulp. Polyaluminium chloride, anionic or cationic polyacrylamide are commonly used in the recovery of white water from papermaking, while cationic polyacrylamide is commonly used in air flotation treatment.