Why Polyaluminum Chloride Production Will Produce Water Insoluble Matter, How to Solve the Problem

    Polyaluminum chloride (PAC) is an inorganic material, an emerging water purification material, inorganic polymer coagulant, referred to as polyaluminum. It is a water-soluble inorganic polymer between AlCl3 and Al(OH)3, with the chemical formula [Al2(OH)nCl6-n]m, where m represents the degree of polymerization and n indicates the degree of neutrality of the PAC product. n=1~5 is a highly charged polymerized cyclic chain with Keggin structure, which has a high degree of electro-neutralization and bridging effect on colloid and particulate matter in water and can It can strongly remove microtoxic substances and heavy metal ions, with stable properties. The test method can be in accordance with the national standard GB 15892-2003 standard test. Due to the bridging effect of hydroxide ions and polymerization of multivalent anions, the polyaluminum chloride produced is an inorganic polymer water treatment agent with large relative molecular mass and high electric charge.

    The reason why polyaluminum chloride produces water insoluble matter:

    The content of water insoluble matter in polyaluminum chloride directly affects whether the products of polyaluminum chloride are qualified or not, and the water insoluble matter of polyaluminum chloride is determined by the different raw materials for production, the different production processes, and the different drying processes, so it needs to be controlled from the source. Most of the traditional polyaluminum chloride is produced by bauxite and industrial waste hydrochloric acid, these raw materials are generally good friends with a large number of impurities, if the production process is not well controlled, it will make the later polyaluminum chloride contains a large number of water-insoluble substances.

    In the water treatment industry, polyaluminum chloride has been recognized as one of the commonly used agents, often used together with polyacrylamide, and general aluminum chloride is different is that they have polymerization, due to the production process, so the time of production may leave part of the water insoluble matter, the need to control, how to control these water insoluble matter?

    1, spray drying method: this equipment process produces polyaluminum chloride of good quality, water insoluble matter is also lower than the standard. 　　

    2, plate and frame filtering process: to make its water insoluble matter to reach the target, natural accumulation, to control the water insoluble matter through the natural accumulation method, in addition to the original material aspects of strict control, accumulation time is also very important, generally to pile up 3-5 days to reach the standard. 　　

    3, control of raw materials: the use of aluminum hydroxide powder production can greatly reduce the polyaluminum chloride water insoluble matter, and the use of calcium aluminate powder and bauxite production goods if the production process is not well controlled, the water insoluble matter is likely to be overspent.