METHOD OF PRODUCING NITROGEN-PHOSPHORUS FERTILIZERS BY WAY OF PROCESSING SOLUTIONS OBTAINED IN PROCESS OF ACID EXTRACTION OF PHOSPHORUS-CONTAINING RAW MATERIAL Russian patent published in 1997 - IPC

FIELD: production of mineral fertilizers. SUBSTANCE: invention may be used in chemical industry and hydrometallurgy when processing phosphorus-containing raw material in process of production of granulated complex nitrogen- phosphorus fertilizers. In particular, in a method of producing such fertilizers using processing of solutions resulting from acid extraction of phosphorus-containing raw material including ammoniation of these solutions and stripping of ammoniated sludge on multiple-effect evaporator unit to residual moisture 10-30% followed by granulation and drying of final product, stripped ammoniated sludge is additionally stripped on evaporation plant by 2-4% and heated prior to be granulated and dried to a temperature by 7-20 C exceeding maximum temperature of sludge when being stripped. EFFECT: intensified process, reduced power consumption. 1 dwg, 1 tbl