GRANULAR NITROGEN FERTILISER BASED ON AMMONIUM NITRATE AND CARBAMIDE AND METHOD OF PRODUCING SAID FERTILISER Russian patent published in 2010 - IPC C05C1/00 C05C13/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a composition and a method of producing nitrogen fertiliser based on ammonium nitrate and carbamide and a sulphate additive and can be used in chemical industry for producing a new type of fertiliser known as granular UAN fertiliser. The method involves production of granular nitrogen fertiliser based on ammonium nitrate, carbamide and a sulphate additive whose granules contain an ammonium nitrate nucleus, an outer carbamide shell and an intermediate ammonium sulphate layer. The fertiliser contains 37-41% nitrogen and 1-3% sulphate sulphur. The fertiliser is obtained through successive deposition onto ammonium nitrate granules of an aqueous suspension of ammonium sulphate with simultaneous drying and fusion of carbamide and subsequent cooling of the end product. The amount of deposited ammonium sulphate is kept in the range of 80-210 kg per ton of ammonium nitrate. Concentration of ammonium sulphate in the aqueous suspension is kept in the range of 55-70%. Mass ratio of carbamide to ammonium nitrate in the end product is kept in the range of (0.5-1.5) :1.

EFFECT: more efficient production of nitrogen fertiliser based on ammonium nitrate and carbamide with a sulphate additive.

6 cl, 2 tbl, 1 ex