UREA GRANULATION IN FLUIDISED BED AND CORRESPONDING APPARATUS Russian patent published in 2016 - IPC B01J2/16 

FIELD: chemistry; technological processes.

SUBSTANCE: invention relates to granulation of urea. Described is a method of preparing granulated urea by granulating a urea solution in a fluidised bed, taking place along a substantially longitudinal growth path, from a granulation starting end (1_S) to a product discharge end (1_E) of said fluidised bed. Urea solution enters the fluidised bed by means of several urea inputs (2_A, 2_B, 2_C) taken from a main urea feed (2), where an additive (6) is mixed with said urea solution, said additive has a non-uniform concentration in said urea inputs, so that at least two of said urea inputs have a different concentration of additive. Additive is divided into a plurality of additive streams (6_A-6_C), and each additive stream is mixed directly with a respective urea input (2_A-2_C).

EFFECT: invention allows controlling concentration of additive in different layers of granules.

7 cl, 9 dwg