METHOD FOR PREPARING DUST-REMOVED POTASSIUM FERTILIZER Russian patent published in 2003 - IPC

FIELD: inorganic chemistry, fertilizers. SUBSTANCE: invention relates to technology for preparing potassium chloride from sylvinite ores with reduced content dust fractions in it. Method involves dissolving ore, crystallization of potassium chloride from forming hot saturated solution in multiple-step vacuum- crystallizing unit to yield suspension with saturation degree of liquid phase up to 0.98 by sodium chloride, classification of suspension solid phase for large-crystalline and small-crystalline fractions of potassium chloride, drying and dust-removing of large-crystalline fraction. Then filtered-off moisture small-crystalline fraction of potassium chloride is subjected for storage at environment temperature, drying and dust-removing with addition of isolated dust-like fraction to moisture solid phase feeding to the storage. After storage moisture small- crystalline fraction of potassium chloride is dried in common with large-crystalline fraction of the main flow or separately. Method allows preparing dust-removed potassium fertilizer potassium chloride with simultaneous simplification of process due to exclusion of technological stages of dissolving small-crystalline fraction and crystallization of potassium chloride and reduction of consumptions also. EFFECT: improved preparing method. 2 cl, 1 tbl