A kind of recovery and utilization method of carnallite liquid in the production of potassium chloride

Abstract

The invention discloses a recycling method for a carnallite post-throwing liquid in production of potassium chloride. The recycling method comprises the following steps: after separating carnallite which is settled by a carnalite settler by a centrifugal machine, washing the solid in a trough and conveying the solid to a speed control crystallizer; buffering the post-throwing liquid by virtue of a post-throwing liquid tank, conveying the post-throwing liquid to a post-throwing liquid settler and conveying a salt slurry which is settled by the post-throwing liquid settler to a high-temperature salt dosing step for production of industrial refined salt and magnesium sulfate monohydrate; and conveying an overflowing liquid in the upper layer by using the post-throwing liquid settler and the carnalite settler to an industrial bromine production step for production of industrial bromine. According to the method disclosed by the invention, the quality of a carnallite product in production of potassium chloride is improved, so that the content of potassium chloride in the carnallite product is reduced, the water consumption in a decomposing and washing step is reduced, the washing yield of potassium chloride is improved, the loss of potassium chloride in the washing process is avoided, and meanwhile, the potassium chloride product is improved, so that the targets of improving the quality and reducing the consumption are achieved.

Description

[0001] Field: [0002] The invention relates to a production method of potassium chloride, in particular to a method for recycling carnallite after-slipped liquid in the production of potassium chloride. Background technique: [0003] Carnallite, whose molecular formula is KCl MgCl 2 ·6H 2 O, the molecular weight is 277.87. Produced as colorless orthorhombic granular or dense aggregates, crystals are rare. The relative density is 1.6. It is widely used in the manufacture of potash fertilizers and mineral raw materials for extracting magnesium metal. It is mainly used as a refining agent for refining magnesium and as a protective agent for producing aluminum-magnesium alloys. It is also used as a welding agent for aluminum-magnesium alloys, as a flux for metals, and as a raw material for the production of potassium and magnesium salts. [0004] At present, the extraction of potassium chloride from potassium-containing brine at home and abroad, whether it is cold decomposi...

AI Technical Summary

Problems solved by technology

Because the content of sodium chloride in the liquid after carnallite is high, long-term cyclic settlement will inevitably lead to the increase of NaCl content in carnallite, which will affect the quality of carnallite products, and then affect the production of potassium chloride products

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