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:
Nov. 02, 1999
Filed:
Apr. 02, 1997
Jeremy D Peter-Hoblyn, Cornwall, GB;
Eric N Balles, Carlisle, MA (US);
John E Hofmann, Naperville, IL (US);
Theodore J Tarabulski, Brewster, NY (US);
Clean Diesel Technologies, Inc., Stamford, CT (US);
Abstract
A safe, reliable SCR system for reducing NO.sub.x emissions from a lean-burn internal combustion engine utilizes urea in aqueous solution. Overheating and hydrolysis of the solution are prevented by maintaining the temperature of the urea solution sufficiently low that it is not permitted sufficient time at elevated temperature to hydrolyze the urea to such an extent that solids precipitate. In a preferred embodiment, an injector system similar to those used for fuel injection provides a constant feed to injectors and a return line. The feed and injection can be controlled to provide sufficient urea for NO.sub.x reduction and sufficient cooling capacity for the feed and injection system to avoid hydrolysis and deposits of hydrolysis products.