The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 12, 1982
Filed:
Sep. 01, 1981
Toyo Engineering Corporation, Tokyo, JP;
Mitsui Toatsu Chemicals, Inc., Tokyo, JP;
Abstract
In a synthesis of urea using ammonia in a highly excessive molar ratio, unreacted materials are decomposed and separated by subjecting the urea synthesis effluent to a stripping step using carbon dioxide at a pressure equal to the urea synthesis pressure. The thus-separated gaseous mixture of ammonia and carbon dioxide is condensed through an indirect heat exchange with an effluent stream discharged from the stripping step and lowered to a predetermined pressure level. Resulting condensation heat is used for the decomposition and separation of unreacted materials still remaining in said effluent stream. By choosing suitable operation conditions for each step of the present invention, it is possible to reduce the amount of high pressure steam to be required and to minimize the amount of low pressure steam to be recovered.