1975 Logemann Stamicarbon 3867442 Urea Process
This invention describes a process for producing urea by reacting ammonia and carbon dioxide is described wherein the ammonium carbamate present in the synthesis effluent is decomposed under high pressure, the gas mixture resulting therefrom is at least partially condensed under a high pressure and the gas-liquid mixture produced in the condensation zone is introduced into the synthesis zone. The ammonia and carbon dioxide still present in the synthesis solution after the high pressure decomposing of the ammonium carbamate are removed under a low pressure whereby an ammonium carbamate solution is produced, which is used as a washing agent for recovering ammonia and carbon dioxide from the inerts containing gas mixture discharged from the synthesis zone. The wash solution thus obtained is introduced in the condensation zone, together with a quantity of urea containing solution from the synthesis zone, by means of a jet pump driven by fresh ammonia.
This describes a Stamicarbon CO2 stripping still in operation today.