Polyaluminium chloride is a kind of water purification materials, inorganic polymer coagulant, was simply known as poly aluminum, 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 press is divided into different colors, brown, beige, yellow and white liquid can be rendered as colorless transparent, light yellow, light yellow to tan.