1981 Gorlovsky 4256662 Urea Process
This invention describes an improvement in a conventional total recycle urea process. Urea solution is concentrated in a vacuum section. The vapors from this section are condensed under a pressure of 0.04 to 0.90 ata by means of indirect cooling water, followed by contacting the uncondensed vapors with an aqueous solution of unconverted starting feed at a temperature in the range of 10 to 60 degC and pressure in the range of 1.5 to 18 ata for further absorption condensation. This results in a steam consumption reduction of 100 to 250 kg/mt and a cooling water consumption reduction of 6 to 14 m3/mt.