Patent ID: 8763369
Filing Date: 2014-07-01
Classification: B01D,F01N,Y02T

Abstract:
1. An exhaust gas treatment system for an internal combustion engine, the system comprising: an exhaust gas conduit in fluid communication with, and configured to receive an exhaust gas from, the internal combustion engine and to conduct the exhaust gas between a plurality of devices of the exhaust gas treatment system; a hydrocarbon injector connected to the exhaust gas conduit in fluid communication with the exhaust gas for delivery of hydrocarbon thereto and formation of an exhaust gas and hydrocarbon mixture; a reductant injector connected to the exhaust gas conduit and in fluid communication with the exhaust gas for delivery of a reductant thereto; a selective catalyst reduction device disposed in fluid communication with the exhaust gas conduit downstream of the hydrocarbon injector and reductant injector and configured to receive and to mix the exhaust gas and hydrocarbon mixture and to reduce NO a first oxidation catalyst device disposed in fluid communication with the exhaust gas conduit downstream of the selective catalyst reduction device and configured to oxidize the exhaust gas and hydrocarbon mixture to raise the temperature of the exhaust; a second oxidation catalyst device disposed in fluid communication with the exhaust gas conduit upstream of the selective catalyst reduction device and configured to oxidize carbon monoxide and engine-out hydrocarbon; a particulate filter assembly having an exhaust gas filter for collection of carbon and particulates disposed therein, in fluid communication with the exhaust gas conduit and located downstream of the first oxidation catalyst device for receipt of the heated exhaust gas and combustion of carbon and particulates collected in the exhaust gas filter, wherein the hydrocarbon injector is connected to the exhaust gas conduit upstream of the selective catalyst reduction device and the second oxidation catalyst, and the reductant injector is connected to the exhaust gas conduit upstream of the selective catalyst reduction device and downstream of the second oxidation catalyst device; a temperature sensor configured for fluid communication with the exhaust gas conduit upstream of the hydrocarbon injector and configured to generate a signal indicative of a temperature of the exhaust gas; and a controller in communication with the temperature sensor and the hydrocarbon injector and configured to adjust the rate of hydrocarbon delivery from the hydrocarbon injector to maintain a desired exhaust gas temperature to burn carbon and particulates in the exhaust gas filter.