PHOSPHORUS-POTASSUIM-NITROGEN-CONTAINING NPK-FERTILISER AND METHOD FOR PRODUCING GRANULATED PHOSPHORUS-POTASSUIM-NITROGEN-CONTAINING NPK-FERTILISER Russian patent published in 2017 - IPC C05C1/00 C05G1/00 A01P21/00 

FIELD: agriculture.

SUBSTANCE: complex nitrogen-phosphorus-potassium fertiliser (NPK) contains ammonium nitrate, monoammonium phosphate, anhydrous calcium sulfate, potassium nitrate, ammonium chloride, wherein the mass fraction of total nitrogen is from 13-15%, the mass fraction of total phosphates in terms of P₂O₅ is from 11-15%, the mass fraction of potassium in terms of K₂O is from 7-8%. The method for producing a complex NPK fertiliser from a solid phosphate salt representing a mixture of fluorapatite Ca₅(PO₄)₃F and dicalcium phosphate CaHPO₄×nH₂O, where n is from 0 to 2, and the content of fluorapatite Ca₅(PO₄)₃F from 27 to 99% includes the stage of said solid phosphate salt decomposition with sulfuric acid by the semi-dry method, the stage of adding potassium chloride as a source of potassium, ammonium nitrate as a source of nitrogen, the stage of preparing NPK slurry, and also the stage of granulating and drying the finished product.

EFFECT: inventions allow to improve the properties of NPK-fertiliser, to increase the strength of granules, to solve the problem associated with the plasticity of granular complex fertilisers.

14 cl, 1 dwg, 3 tbl, 3 ex