PAC (Polyaluminium Chloride) referred to PAC. Also commonly referred to as basic aluminum chloride or the like coagulant, it is between ALCL3 and AL (OH) 3 between a water-soluble inorganic polymer, a chemical formula [AL2 (OH) NCL6- NLm] wherein m represents the degree of polymerization, n represents the degree of PAC neutral product. Color yellow or light yellow, dark brown, dark gray resin-like solid. The product has a strong bridge adsorption performance, during hydrolysis, condensation, adsorption and precipitation accompanied by other physical and chemical processes take place. The fundamental difference between PAC and traditional inorganic coagulant that traditional inorganic coagulant for low molecular weight crystalline salt, and PAC's structure consists of diverse and varied forms carboxyl complex composition, flocculation and sedimentation speed, applicable PH value range, non-corrosive pipe equipment, water purification effect is obvious, can effectively support in addition to the water color quality SS, COD, BOD, and arsenic, mercury and other heavy metals, which are widely used for drinking water, industrial water and wastewater treatment fields. Usage: 1, the solid product by 1: 3 dissolved in water as a liquid, the diluted water plus 10-30 times the required concentration. 2, the amount according to the different turbidity of raw water, determine the optimal dosage, usually raw water turbidity in 100-500mg / L, each kiloton dosage 10-20kg. Packaging and storage: 1, lined with plastic bags, outer layer of plastic film woven bag weighs 25kg. 2, stored in a cool, dry place to prevent the sun and rain.