METHOD OF PRODUCING LIQUID FERTILIZER AT DECREASED AMMONIUM CONTENT Russian patent published in 1998 - IPC

FIELD: chemical technology, fertilizers. SUBSTANCE: invention relates to production of liquid nitrogen fertilizers based on carbamide and ammonium nitrate. Fertilizer is produced by mixing hot carbamide and ammonium nitrate solutions and water followed by cooling mixture obtained. Carbamide solution has 0.2-0.8% ammonia as impurity excess of that should be neutralize in the process of fertilizer producing so that residual ammonia content will not above 0.1% (under pH value control). Nitric acid is dosed to ammonium nitrate solution up to its content 0.3-2.6 wt.-% in acidified solution. Carbamide solution is mixed preliminary with cooled recirculating mixture that ensures to decrease temperature of an intermediate mixed solution to 45-75 C and then ammonium nitrate acidified solution is added to an intermediate solution. Then water and ammonia are added to ammonium nitrate solution before its acidification up to concentration 0.05-0.10% HNO₃ in solution. EFFECT: improved method of fertilizer producing. 3 cl