METHOD FOR PREPARING COMPLEX NPK-FERTILIZER WITH REGULATED RATIO OF NUTRIENT SUBSTANCES Russian patent published in 2003 - IPC

FIELD: fertilizers. SUBSTANCE: invention relates to manufacture of complex triple fertilizers containing potassium chloride of sulfate. Ammonium nitrate is added to product of decomposition of phosphate raw with acid after preliminary removing excess of calcium salts, mixture is neutralized with ammonia, evaporated and prepared pulp with pH 3.0-5.5 is mixed with potassium chloride or sulfate. Components are taken in amount providing the mass ratio ammonium nitrate to potassium salt in ready product = 1.6:1, not less. By regulation of amount of adding ammonium nitrate and potassium sulfate or chloride fertilizer is prepared with the ratio of nutrient substances N : P₂O₅ : K₂O in the limits (1-12) : (0.5-6) : 1, respectively. Method allows retention of pulp mobility at stage of mixing with potassium salt and feeding into granulator-drier that provides stabilization of working mixer and sprayers for mixture spraying. EFFECT: improved preparing method. 2 cl, 2 tbl