Cationic polyacrylamide is one of the commonly used agents for sewage treatment and sludge dehydration, and its role is self-evident, who knows who uses it. Some customers often encounter the use of cationic polyacrylamide is not good situation, what is the reason?
It is necessary to choose the right PAM, anions and cations cannot be replaced. Ensure that the characteristics of sewage and sludge do not change. If the above problems have been determined or not solved, please continue to look at the following reasons will affect the use of cationic polyacrylamide effect:
1, the key factor that determines the solubility of cationic polyacrylamide is its dissolution time, and directly affects the use effect. Cationic polyacrylamide should be dissolved by stirring heating measures, so that the product slowly added to the container, to avoid caking, the solution should be prepared at an appropriate temperature, and should avoid mechanical shear for a long time, otherwise it will cause polymer degradation, affecting the use of the effect. In the case of dissolved cationic polyacrylamide, the macromolecular structure of PAM is fractured by high speed stirring or strong shear. Therefore, when preparing PAM solution, the stirring speed should be reasonably controlled to prevent the reduction of molecular weight and flocculation.
2, cationic polyacrylamide powder can be stored in a dry, cool place for more than two years, and the storage time is limited after preparation. Generally speaking, when the concentration is 0.1%, the storage time of non-ionic and anionic solutions shall not exceed one week, and the storage time of cationic solutions shall not exceed one day.
3, add a very small amount of iron compounds or iron powder in PAM solution, stir to disperse it, the viscosity and flocculation of polypropylene solution is greatly reduced, which is why in enamel, galvanized, aluminum or plastic barrels to configure cationic polyacrylamide solution. Compared with anionic polyacrylamide, cationic polyacrylamide is more sensitive to iron, calcium and magnesium ions. Under the catalytic action of cationic polyacrylamide, iron ions undergo chemical reactions. Therefore, the preparation, transfer and storage of cationic polyacrylamide solution should be as far as possible using stainless steel, plastic, glass steel and other reinforced plastics coated with resin carbon steel containers to avoid iron ions entering and contacting with the solution.
