Patent ID: 11878957
Assignee: TOYO ENGINEERING CORPORATION
Field: Chemical engineering (Chemistry)
Classification: CPC C  B  Y | IPC C

Claim 8:
9. The process for urea production according to claim 1, comprising a recovering step comprising absorbing and condensing, in an absorption medium, at least one gas of the following gas I and gas II:
gas I is a gas remaining uncondensed in the condensation step, and
gas II is a gas obtained as a gas phase separated in a purification step when the process for urea production comprises the purification step, and
simultaneously cooling the absorption medium, which has absorbed the at least one gas, to obtain a recovered liquid containing ammonia and carbon dioxide, wherein
the purification step is a step comprising heating, at a pressure lower than the pressure in the high-pressure decomposition step and higher than atmospheric pressure, the urea synthesis solution after being processed in the high-pressure decomposition step to generate a gas phase and a liquid phase, and by separating the gas phase, obtaining a urea synthesis solution having an increased urea concentration and generating a low-pressure steam condensate, a part of the low-pressure steam generated in the condensation step being used as a heat source for heating the urea synthesis solution after being processed in the high-pressure decomposition step,
the cooling in the recovering step is performed by heat exchange with hot water, and
the heating in step b) is performed by heat-exchanging the hot water, after being used for the cooling in the recovering step, with the steam condensate obtained from step a).