METHOD FOR PREPARING GRANULATED COMPLEX NITROGEN-MAGNESIUM FERTILIZER Russian patent published in 2003 - IPC

FIELD: fertilizers. SUBSTANCE: invention relates to technology for preparing granulated complex nitrogen-magnesium fertilizers. Method for preparing granulated complex nitrogen-magnesium fertilizers involves mixing carbamide and magnesium oxide, heating fertilizer-mixture to carbamide melting point and granulation of fertilizers. Magnesium oxide is fed in the amount 10-55% and carbamide, the balance. Granulation of fertilizers is carried out by rapid cooling the melt and grinding the prepared crystallizate. The rate of cooling the melt up to onset moment of crystallization is maintained 5 degrees/min, not less. Calcined magnesite powder is used as magnesium oxide. Method provides the enhancement of mechanical strength of granules and to obtain fertilizer with the enhanced content of magnesium component that composes 12.8-28.2%. Invention can be used in chemical plants producing complex granulated fertilizers based on carbamide (urea). EFFECT: improved preparing method. 3 cl, 1 tbl