The prosperous polyaluminium chloride is a kind of inorganic polymer coagulant, also known as poly aluminum, basic aluminium chloride, poly aluminum chloride, compound polyaluminium chloride. Abbreviations for PAC, due to the effect of bridge of the hydroxyl ions and polyvalent anions polymerization production, charge higher molecular weight of inorganic polymer water treatment agent. On the form and can be divided into two kinds of solid and liquid, solid according to different colors is divided into brown, beige, yellow and white, different colors of polyaluminium chloride on the application and production technology are also a large difference between the two.