FIELD: chemistry.
SUBSTANCE: invention relates to production of urea, where ammonia reacts with carbon dioxide in a high-pressure reactor to obtain a mixture which undergoes autothermal desorption to obtain a stream of gases which contains ammonia and carbon dioxide, and a stream of liquid which contains urea and a carbamate residue in an aqueous solution. The obtained stream of gases undergoes desorption treatment in apparatus working at average pressure, from which the a stream of gas containing ammonia and carbon dioxide is extracted and a mixture of liquid and gas is obtained from the said gas stream after partial condensation. Non-condensed gases which contain ammonia and carbon dioxide are separated from the liquid in a separator and washed in the part of a column filled with packing in counterflow with a stream of carbamate solution to obtain a stream of gas which essentially consists of ammonia and a stream of liquid which contains carbamate solution in which carbon dioxide is absorbed from the non-condensed gases.
EFFECT: extraction of a stream of carbon dioxide gas and is recycling in a synthesis reactor.
13 cl, 3 dwg
