METHOD OF OBTAINING POTASSIUM CHLORIDE Russian patent published in 2013 - IPC C01D3/08 

FIELD: chemistry.

SUBSTANCE: invention can be used in chemical industry. method of obtaining potassium chloride from sylvinites includes their dissolving, crystallisation of target product from solution in multi-step vacuum-crystallisers, separation of crystallisate, drying, dedusting, dissolving small fractions from stage of drying in heated water with obtaining suspension with ratio of liquid to solid L:S=1.0-5.0 and its supply to crystallisation. Drying with dedusting of entire target product is carried out at temperature 100-140 °C. Finely crystalline potassium chloride, obtained in dedusting, is mixed with water, heated to temperature 45-65 °C, with obtaining suspension with minimal L:S, ensuring its transportation along pipeline into first cases of vacuum-crystallisation installation (VCI). Condensate from surface heat-exchangers of VCI is distributed to cases proportionally to difference of temperatures between them. Consumption of water for preparation of suspension and in VCI cases equals to consumption of water, necessary for prevention of sodium chloride crystallisation in vacuum-crystallisation of target product.

EFFECT: invention makes it possible to obtain dedusted target product with application of unregulated multi-step vacuum-crystallisation installations.

2 cl, 2 tbl, 2 ex