Halogen-blended process of preparing low-sodium carnallite

Abstract

The preparation process of low-sodium carnallite features that the subtype magnesium sulfate bittern as material is prepared into low-sodium carnallite through natural evaporation in saltern to separate out solid salt and to obtain bittern with Mg ion content not less than 7.0 %, subsequent blending with mixed potassium salt in the weight ratio of 1-3 to produce crystallization reaction, and filtering. The present invention has simple process and convenient operation, and the low-sodium carnallite product produced directly from bittern has sodium chloride content of 1.35 %, purity up to 98 % and no floatation chemical contained. The blending process has single time potassium ion recovering rate up to 66.50 %. The said technological process has no environmental pollution.

Description

technical field [0001] The invention relates to a method for preparing carnallite, in particular to a method for preparing low-sodium carnallite by a brine mixing method. Background technique [0002] In the prior art, the Chinese patent application with the publication number 1275531 and the application number 00112360.2 discloses a method called "Method for directly producing low-sodium and high-quality carnallite", which is a kind of Add the solid bischofite to the brine in the crystallization stage of carnallite. After stirring, use the Baume degree measurement to adjust the change of the feeding amount. After reaching the required Baume degree, the material can be discharged for liquid-solid separation. The obtained solid phase is finished low-sodium carnallite and high-quality carnallite, and the discharged liquid phase is combined with the overflow liquid to be combined with the old brine, and the old brine can be remade into solid bischoflit...

AI Technical Summary

Problems solved by technology

This method requires the bischofzite to be relatively pure, that is, the content of NaCl and insolubles in the bischoftite is relatively small, otherwise the bischnite needs to be dissolved separately to the required Baume degree, and then the insolubles are removed, and the The clear liquid is then mixed with the brine at the point of carnallite to obtain low-sodium carnallite, which makes the process more complicated

And when the bicholorite is dissolved to the required Baume degree, if you want to remove the insoluble part, it will inevitably cause the loss of the clear liquid (caused by the higher content of the adsorption mother liquor after filtration), thus causing the magnesium bichloride The consumption of carnallite increases, and the cost of low-sodium carnallite increases

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