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:
Feb. 23, 1982
Filed:
Sep. 11, 1980
Applicant:
Inventors:
Toyoyasu Saida, Fujisawa, JP;
Takatatsu Shimokawa, Mobara, JP;
Yuzuru Yanagisawa, Mobara, JP;
Takashi Nagahama, Mobara, JP;
Koji Ishida, Mobara, JP;
Assignees:
Toyo Enginnering Corporation, Tokyo, JP;
Mitsui Toatsu Chemicals Incorporated, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D / ;
U.S. Cl.
CPC ...
159 / ; 159 49 ; 159 / ; 159 / ; 564 73 ;
Abstract
Disclosed is a process for concentrating aqueous urea solutions in which an aqueous urea solution is allowed to flow as a falling film in countercurrent contact with a stream of hot inert gas to concentrate it to 95-99% by weight and the aqueous urea solution so concentrated is then passed through a packed zone in cocurrent contact with a stream of hot inert gas to concentrate it to not less than 99.5% by weight.