Technical process for producing chloride aluminum

Abstract

A technique for preparing polyaluminium chloride is characterized in that: the technique controls the water insoluble substances by a two-step coagulating sedimentation method and comprises the steps of: (1)generating aluminic acid solution by the reaction of aluminium-containing raw material and hydrochloric acid in an acid-proof vessel, adding acid soluble coagulant to execute coagulating sedimentation, and then picking up the supernatant as mother liquor; (2)adding water into the mother liquor obtained in step (1), and heating up in an acid-proof vessel, and then adding calcium aluminate to react in atmospheric pressure, finally adding polymerization coagulant; (3)precipitating to obtain the supernatant which is liquid PAC, obtaining solid PAC by means of drying. The present invention has the advantages of that: the two-step coagulating sedimentation method can overcome the problem of that the control and reduction of the water insoluble substances in PAC preparing process, which uses calcium aluminate as raw material, is hard, the operation is simple, the cost is lower, the settling time can be reduced at 10~20 times, the operability is better, the economic benefit is obviously and each index of the PAC product can satisfy the national standard.

Description

technical field [0001] The invention relates to water purifying agent technology, in particular to a process for producing polyaluminum chloride, which mainly uses two-step coagulation and sedimentation to control water-insoluble matter, and produces polychlorinated polychloride that meets national standards, has low cost, and is of good quality. Aluminum (PAC) water treatment agent. Background technique [0002] With the development of my country's environmental protection industry, polyaluminum chloride (PAC) has been fully used as an efficient water treatment agent in China. However, the traditional polyaluminum chloride production process adopts "pyrolysis method", "neutralization method", "gel method", "double acid method" and other processes, all of which have disadvantages such as long process flow and high production cost. The acid-dissolving one-step method of using calcium aluminate as the raw material for PAC production or the one-step method of mixing acid-disso...

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Problems solved by technology

[0003] However, the current problem is that whether calcium aluminate acid-dissolving one-step method is used or other aluminum-containing raw materials are combined with calcium aluminate mixed acid-dissolving one-step method (commonly known as one-pot cooking), there will be a large amount of calcium aluminate produced in the acid-dissolving production process. The problem that calcium chloride suspension is difficult to effectively separate from PAC solution has resulted in serious excess of water-insoluble matter in PAC finished products, which is still difficult to solve at present

However, the production cost of this process is high, and only a few manufacturers use this process for export products, which makes the promotion of this process slow

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