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:
Mar. 11, 2008
Filed:
Mar. 10, 2006
Wenzhong Zhang, Savage, MN (US);
Julian A. Imes, Bloomington, MN (US);
Todd R. Taubert, St. Paul, MN (US);
Timothy L. Ricke, Savage, MN (US);
Theodore G. Angelo, St. Paul, MN (US);
Wenzhong Zhang, Savage, MN (US);
Julian A. Imes, Bloomington, MN (US);
Todd R. Taubert, St. Paul, MN (US);
Timothy L. Ricke, Savage, MN (US);
Theodore G. Angelo, St. Paul, MN (US);
Donaldson Company, Inc., Minneapolis, MN (US);
Abstract
A diesel exhaust treatment system is disclosed that includes first and second diesel particulate reduction devices. The first diesel particulate reduction device is located upstream in the exhaust flow and contains an oxidation catalyst coating. The second particulate reduction device is located downstream from the first particulate reduction device and is generally non-catalyzed or lightly catalyzed. Each particulate reduction device comprises a flow-through fabric-type filtration media with substantial internal turbulence. As exhaust gas passes through the catalyzed upstream particulate reduction device, nitric oxide (NO) is oxidized to form nitrogen dioxide (NO), a portion of which interacts with the particulate trapped within the upstream diesel particulate reduction device to regenerate the upstream device. A remaining portion of exhaust gas containing NOenters the downstream diesel particulate reduction device, where an additional portion interacts with the trapped particulate to regenerate the device. The relative volume weighted efficiency of the upstream particulate reduction device and of the downstream particulate reduction device are selected to optimize the overall system particle capture efficiency and backpressure, as well as to balance the amount of NOmade with the amount of NOconsumed so as to minimize NOemissions.