METHOD OF PRODUCTION OF GRANULATED SUPERPHOSPHATE Russian patent published in 2002 - IPC

FIELD: manufacture of simple granulated superphosphate from apatite as mineral fertilizer. SUBSTANCE: method includes mixing apatite with absorption runoff at simultaneous mechanochemical activation and grinding it to sizes of apatite particles when residue on 0.036-mm sieve ranges from 5 to 35% of total mass of particles; this mixture is subjected to subsequent decomposition at one stage at temperature of 80 to 90 C at introduction of neutralizing additive; chalk is used as such additive which is introduced in pulp in the amount sufficient for reduction of free acid in it by 1.9 to 2 times ; it is introduced into granulation and drying stage or is used for neutralization of ready granules. EFFECT: possibility of producing simple superphosphate from one kind of raw material at high decomposition coefficient. 2 cl, 3 ex