METHOD OF PRODUCING WATER-RESISTANT AMMONIUM NITRATE GRANULES (VERSIONS) Russian patent published in 2015 - IPC C06B45/30 C06B31/28 

FIELD: chemistry.

SUBSTANCE: invention relates to production of granular ammonium nitrate encapsulated with a relatively water-resistant coating, which can be used to produce industrial explosives, particularly water-resistant igdanites, granulates, grammonites, and in production of nitrogenous fertilisers used in agriculture. A method of producing water-resistant ammonium nitrate granules, wherein each granule is coated with a layer of a water-soluble combustible material, and then with a layer of a crosslinked aqueous gel of a concentrated solution of the same ammonium nitrate or a mixture of ammonium nitrate solutions and/or with a carbamide solution with equilibrium concentration at temperature of 0-20°C. The coating of the aqueous gel is then fixed by adding a gelling agent and/or crosslinking agent to the gel. Polymerisation is carried out for 2-20 minutes at 15-60°C, while simultaneously mixing components until the gel coating is fixed on the granules in the form of a film with thickness of 0.1-2 mm. According to another version of the method of producing ammonium nitrate granules, each ammonium nitrate granule is first coated with a layer of a water-resistant crosslinked aqueous gel of a concentrated solution of the same ammonium nitrate or a mixture of ammonium nitrate solutions and/or with a carbamide solution with equilibrium concentration at temperature of 0-20°C. Subsequent operations are carried out similar to the first version of the method.

EFFECT: reduced fire and explosion hazard, improved explosion and energy characteristics when used as an industrial explosive and environmental safety when used as fertiliser for agriculture.

10 cl, 1 tbl