METHOD OF PROCESSING PHOSPHATE RAW TO DEFLUORINATED PHOSPHATE Russian patent published in 2003 - IPC

FIELD: inorganic chemistry, fertilizers, chemical technology. SUBSTANCE: invention relates to methods of processing phosphate raw to defluorinated phosphates used as fertilizers and fodder product. Method of processing phosphate raw to defluorinated phosphate involves mixing phosphate raw with phosphoric acid and alkaline agent and the following calcinations of charge. Phosphate raw taken in the amount 4.5-6.5% of total mass is mixed with wet-process phosphoric acid and alkaline agent up to ratio CaO:Na₂O: P₂O₅ = (0.25-0.34) : (0.1-0.45) : 1, respectively. Filtrate is separated and mixed it with remained part of phosphate raw and alkaline agent. The proposed method provides the high quality of ready product, decrease consumption of alkaline reagent and enhanced safety of technological regime. Calcination technological regime is stable and process carried out without formation of crusts as soda decarbonization does not occur under these conditions. EFFECT: improved method of processing. 1 tbl, 3 ex