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:
Jan. 24, 1995
Filed:
Nov. 05, 1993
Jing M Lee, Stafford, TX (US);
Other;
Abstract
An improved process for manufacturing melamine from urea simplifies the recovery of melamine, carbamate and ammonia from a fluidized bed reactor effluent stream by operating the process at a pressure between 1.4 and 2 MPa. In such a manner, a carbamate solution can be produced at a sufficiently high concentration for use in a urea plant without an intervening concentration step. In addition, ammonia recycled as a fluidizing gas can be condensed against cooling water to permit easy separation of noncondensables such as oxygen which used in the process as a passivator for carbamate corrosion inhibition. The melamine product is produced as an aqueous solution free of melamine solids. Heat is recovered from the carbamate condensation and used for the vaporization of ammonia which is recycled to the reactor for fluidization.