METHOD OF MAKING COMPLEX FERTILIZER BRIQUET OF THE PROLONGED ACTION Russian patent published in 1997 - IPC

FIELD: mineral fertilizers. SUBSTANCE: granules and/or powder of mineral fertilizers were mixed with 0.1-0.3% addition as ammonium sulfate or its an aqueous solution, or mineral chlorineless acid, or a mixture of ammonium sulfate or mineral chlorineless acid with pyrite cinder. Binding agent: 10-40% urea solution in an aqueous formalin at molar ratio = (0.4-0.6): (0.8-1.2), respectively, is added to the obtained mixture followed by stirring at 1-30 C for 5-30 min and forming the self-hardening briquets by pressing or extrusion, or casting. EFFECT: improved method of producing. 2 cl, 2 tbl