Patent ID: 8505279
Filing Date: 2013-08-13
Classification: B01D,B01J,F01N,Y02T

Abstract:
1. An exhaust gas treatment system for a diesel engine, comprising: a diesel oxidation catalyst (DOC) in fluid communication with the diesel engine to receive an exhaust gas flow therefrom, the DOC disposed in a DOC housing; a hydrocarbon injection device located between the engine and the DOC that is configured to inject a hydrocarbon, CO, or H a urea selective catalytic reduction (U-SCR) catalyst in fluid communication with the DOC to receive the exhaust gas flow therefrom, the U-SCR catalyst disposed in a U-SCR catalyst housing a second injection device that is configured to inject urea or ammonia, or a combination thereof, into the exhaust gas flow between the diesel engine and the U-SCR; a four-way catalyst in fluid communication with the U-SCR catalyst to receive the exhaust gas flow therefrom, the four-way catalyst comprising a monolithic substrate having a plurality of porous cell walls that incorporates a lean nitrogen oxide (NO a controller that is configured to control operation of the exhaust gas aftertreatment system and periodic and selective injection of the hydrocarbon, CO or H