NITRATION PROCESS FOR PRODUCTION OF NITROGEN FERTILIZERS WITH REDUCED FORMATION OF SAND Russian patent published in 2024 - IPC C05B11/06 C05C5/04 C05D9/02 C05C1/00 C05G1/00 

FIELD: agriculture.

SUBSTANCE: method of nitration process for production of nitrogen fertilizers includes the following stages: a) acidification of phosphorites containing fluorides and SiO₂, with a solution of nitric acid to obtain an acidified solution, wherein the fluorides react with the nitric acid solution, wherein the hydrofluoric acid reacts with the reactive SiO₂ to form SiF₄, wherein the obtained SiF₄ further reacts with hydrofluoric acid to form H₂SiF₆ or directly form H₂SiF₆, b) cooling the acidified solution obtained at step (a) to a temperature at which crystallisation of calcium nitrate occurs, c) neutralizing the reaction mixture obtained in step (b) with ammonia to obtain a mixture of ammonium phosphate, calcium phosphate and ammonium nitrate, d) conversion of calcium nitrate obtained in step (b) into ammonium nitrate and calcium carbonate using carbon dioxide and ammonia, e) separating calcium carbonate from ammonium nitrate in settling vessel (100), wherein at step (a) in section (210) of gas removal of tank (100) for acidification water is added to prevent, control or reduce formation of SiO₂ in gas discharge pipeline. Use of water to reduce formation of sand in the gas discharge pipeline of the nitration process, wherein for acidification to prevent formation of SiO₂ in the gas discharge pipeline, water is added at gas removal section (210) of vessel (100).

EFFECT: inventions make it possible to reduce formation of sand.

9 cl, 3 dwg, 1 tbl