Producing high percentage potassium chloride from polymineralic, magnesium sulfate rich crude potassium salt or from crude salt fraction obtained during dry treatment of crude salt, comprises hot dissolution-cold crystallization process

摘要

Producing high percentage potassium chloride from polymineralic, magnesium sulfate rich crude potassium salt or from crude salt fraction obtained during the dry treatment of the crude salt, comprises hot dissolution-cold crystallization process. The lye for dissolution in the hot dissolution process comprises heated water or a very dilute heated solution with low content of potassium chloride, magnesium chloride and magnesium sulfate. The recycling circulation of the solutions and reusing of potassium chloride saturated mother liquor as lye for dissolution is completely avoided. Producing high percentage potassium chloride from polymineralic, magnesium sulfate rich crude potassium salt or from crude salt fraction obtained during the dry treatment of the crude salt, comprises hot dissolution-cold crystallization process. The lye for dissolution in the hot dissolution process comprises heated water or a very dilute heated solution with low content of potassium chloride, magnesium chloride and magnesium sulfate. The recycling circulation of the solutions and reusing of potassium chloride saturated mother liquor as lye for dissolution is completely avoided. The recyclable material solution separated from insoluble components is evaporated after carrying out desulfation and thus the common salt crystallizes out and the potassium chloride-sodium chloride-crystallizate obtained by the cool crystallization process is worked up by known methods to obtain high percentage potassium chloride.