PROLONGED-EFFECT COMPLEX GRANULATED FERTILIZER WITH TRACE MINERALS AND A METHOD FOR FABRICATION THEREOF Russian patent published in 2002 - IPC

FIELD: fertilizers production. SUBSTANCE: fertilizer based on phosphorite flour, urea, and potassium chloride is prepared by mixing indicated ingredients in proportions: 1:(1.13-4.62):(0.38-0.76), respectively, moistening resulting mixture to 1.8-3.0% moisture, adding 0.02-0.2% antiagglomeration agent (polyglycols), heating to 50-120 C (depending on ingredient composition) to form plastic suspension, granulation at 50- 120 C on roll-, screw-, drum-, or dish-type industrial granulator, and sizing resulting granules. Phosphorite flour contains needed trace minerals in required quantities. General chemical analysis of fertilizer, wt %: total nitrogen (N) 6.0-18.0, total phosphorus (P₂O₅) 8,0-14.9, potassium (K₂O) 6.0-12.0, magnesium (MgO) 1.0-18.0, cobalt 0.005-0.04, zinc 0.02-0.10, copper (0.01-0.03, nickel 0.01-0.03, chromium 0.003-0.05. Random strength of granules is 1.85-2.1 MPa and friability 100%. EFFECT: improved physicochemical characteristics and eliminated dusting and agglomeration. 2 cl, 1 tbl