Patent · US Expired

Method of stripping unreacted materials in urea synthesis process

US4321410A · kind A · utility

24Cited by
6References
6Claims
0Family size

Assignees

Inventors

Key dates

Filing dateMar 3, 1981
Grant dateMar 23, 1982
Priority date
Expiry dateMar 3, 2001

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C273/04
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

In a process in which a urea synthesis effluent obtained by reacting ammonia with carbon dioxide is subjected to a stripping step of bringing the urea synthesis effluent into countercurrent contact with carbon dioxide under heating to obtain an aqueous urea solution containing a small amount of ammonia and ammonium carbamate, the improvement comprises first bringing the urea synthesis effluent is into contact with a separated gas evolved in the stripping step under adiabatic conditions or with a little cooling. The use of the above process enables a reduction in size of the stripper and a recovery of the high pressure steam without keeping the ammonia to carbon dioxide molar ratio lower than that of the conventional method.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.