Anionic Polyacrylamide (APAM) 9003-05-8

Anionic Polyacrylamide (APAM) is a water-soluble synthetic polymer with the formula (C₃H₅NO)ₙ, copolymerized with acrylate monomers to introduce negatively charged carboxylate functional groups. It is one of the most widely used flocculants for mining, water treatment, and industrial applications where positively charged or neutral suspended particles need to be aggregated and removed.

Anionic PAM is best suited for treating suspensions with positively charged particles, such as mineral tailings, coal washing effluent, and alkaline wastewater. It is the preferred choice for mining applications and most inorganic industrial wastewaters. Cationic PAM is better for organic sludge dewatering, while nonionic PAM works well in acidic or high-ionic-strength conditions where charge interference could affect performance.

In mining tailings dewatering, APAM is dosed into the tailings slurry as it flows to thickeners or settling ponds. The polymer bridges fine mineral particles together, forming large, fast-settling flocs. This allows clean water to be recovered and recycled back to the process while producing dense, compact solids for disposal. APAM significantly improves water recovery rates and reduces the footprint required for tailings storage.

In enhanced oil recovery, APAM is injected into oil reservoirs as a mobility control agent. The polymer increases the viscosity of the injected water, improving sweep efficiency and pushing more oil toward production wells. APAM is preferred over hydrolyzed polyacrylamide (HPAM) in some reservoirs due to its controlled charge density and better stability under reservoir conditions.

APAM powder should be stored in a cool, dry place away from moisture and direct sunlight. For solution preparation, the powder should be added slowly to agitated water at room temperature. Typical working solution concentrations are 0.05-0.5%. Solutions should be prepared fresh as they can degrade over time due to microbial activity and mechanical shear. Avoid vigorous, high-shear mixing which can break polymer chains and reduce effectiveness. Under proper dry storage, shelf life is 24 months.