Polyaluminium chloride is a flocculant, which is mainly used to purify drinking water. It is also used for special water quality treatment of water supply, iron removal, cadmium removal, fluorine removal, radioactive pollution removal, oil slick removal, etc. it is also used for industrial wastewater treatment, such as printing and dyeing wastewater. It is also widely used in casting, papermaking, medicine, tanning, etc.