Patent application number | Description | Published |
20090193795 | METHOD AND APPARATUS FOR REGENERATING AN AFTERTREATMENT DEVICE FOR A SPARK-IGNITION DIRECT-INJECTION ENGINE - The disclosure sets forth operating a spark-ignition, direct-fuel injection internal combustion engine equipped with an exhaust aftertreatment system including a lean-NOx adsorber device. The engine is operated substantially un-throttled and at a lean air/fuel ratio and a first fuel pulse is injected to meet an engine output torque during a compression stroke of each engine cycle prior to a spark-ignition event. When regeneration of the lean-NOx adsorber device is commanded, a second fuel pulse is injected during a second engine stroke of each engine cycle. | 08-06-2009 |
20100043402 | PASSIVE AMMONIA-SELECTIVE CATALYTIC REDUCTION FOR NOx CONTROL IN INTERNAL COMBUSTION ENGINES - A method for operating an internal combustion engine includes controlling the engine to a preferred air/fuel ratio to generate an engine-out exhaust gas feedstream including preferred concentrations of nitric oxide, carbon monoxide, and hydrogen, converting the nitric oxide, carbon monoxide, and hydrogen to ammonia across a first catalytic device; and storing the ammonia on an ammonia-selective catalytic reduction device fluidly serially connected downstream of the first catalytic device. | 02-25-2010 |
20100107605 | PASSIVE AMMONIA-SELECTIVE CATALYTIC REDUCTION FOR NOx CONTROL IN INTERNAL COMBUSTION ENGINES - Engine exhaust gas feedstream NOx emissions aftertreatment includes a catalytic device connected upstream of an ammonia-selective catalytic reduction device including a base metal. Engine operation can be modulated to generate an engine-out exhaust gas feedstream that converts to ammonia on the catalytic device. The ammonia is stored on the ammonia-selective catalytic reduction device, and used to reduce NOx emissions in the exhaust gas feedstream. | 05-06-2010 |
20100107606 | PASSIVE AMMONIA-SELECTIVE CATALYTIC REDUCTION FOR NOx CONTROL IN INTERNAL COMBUSTION ENGINES - Engine exhaust gas feedstream NOx emissions aftertreatment includes a catalytic device and first and second ammonia selective catalytic reduction devices. The first and second ammonia-selective catalytic reduction devices each includes a base metal. Engine operation can be modulated to generate an engine-out exhaust gas feedstream that converts to ammonia. The ammonia is stored on the first and second ammonia selective catalytic reduction devices and used to reduce NOx emissions in the exhaust gas feedstream. | 05-06-2010 |
20100139248 | METHOD AND APPARATUS FOR CONTROLLING OPERATION OF A SPARK-IGNITION DIRECT-INJECTION ENGINE - Operation of a spark ignition, direct injection engine having an aftertreatment system including an oxidation catalyst and a selective catalyst reduction device is described. The method includes controlling to a stoichiometric air/fuel ratio and retarding spark ignition timing. Engine fueling is then controlled to a lean air/fuel ratio and spark is retarded. The engine is then operated to generate ammonia reductant. Engine operation then comprises operating at a preferred air/fuel ratio and controlling spark ignition timing to a preferred timing. | 06-10-2010 |
20100139251 | METHOD AND APPARATUS FOR CONTROLLING EXHAUST EMISSIONS IN A SPARK-IGNITION DIRECT-INJECTION ENGINE - Exhaust emissions from a spark-ignition direct-injection engine connected to an oxidation catalytic device and a selective catalyst reduction device having a capacity to store ammonia reductant are controlled. The engine operates in a first combustion mode to generate ammonia reductant, stored on the second aftertreatment device. The engine operates lean of stoichiometry and nitrides of oxygen in the exhaust gas feedstream are reduced on the second aftertreatment device. | 06-10-2010 |
20100186390 | TECHNIQUE FOR PRODUCTION OF AMMONIA ON DEMAND IN A THREE WAY CATALYST FOR A PASSIVE SELECTIVE CATALYTIC REDUCTION SYSTEM - A method for controlling a powertrain includes selectively initiating an ammonia generation cycle, including injecting fuel into a combustion chamber of an engine before a primary combustion event to a calibrated air fuel ratio in a range lean of stoichiometry based upon generation of NOx within the combustion chamber, injecting fuel into the combustion chamber after the primary combustion event based upon an overall air fuel ratio in a range rich of stoichiometry and resulting generation of molecular hydrogen, and utilizing a catalyst device between the engine and a selective catalytic reduction device to produce ammonia. | 07-29-2010 |
20100186391 | TECHNIQUE FOR PRODUCTION OF AMMONIA ON DEMAND IN A THREE WAY CATALYST FOR A PASSIVE SELECTIVE CATALYTIC REDUCTION SYSTEM - A method for controlling a powertrain includes selectively initiating an ammonia generation cycle including injecting fuel into a combustion chamber of an engine before a primary combustion event to a calibrated air fuel ratio in a range lean of stoichiometry based upon generation of NOx within the combustion chamber, injecting fuel into the powertrain after the primary combustion event based upon an overall air fuel ratio in a range rich of stoichiometry and resulting generation of molecular hydrogen, utilizing a hydrogen forming catalyst to reform the injected fuel, and utilizing a catalyst device between the engine and the selective catalytic reduction device to produce ammonia. | 07-29-2010 |
20100293926 | HYDROCARBON SELECTIVE CATALYTIC REDUCTION FOR NOx CONTROL WITH GASOLINE-FUELED SPARK IGNITION ENGINES USING ENGINE-OUT HYDROCARBONS - A method for controlling hydrocarbon delivery to a hydrocarbon selective catalytic reduction device configured to receive an exhaust gas flow from an internal combustion engine includes monitoring measurable variable terms including factors affecting a conversion efficiency in the hydrocarbon selective catalytic reduction device, determining classifications of the measurable variable terms based upon measurable variable ranges, determining a desired hydrocarbon delivery value range based upon the classifications; and utilizing the desired hydrocarbon delivery value range to control the hydrocarbon delivery to the hydrocarbon selective catalytic reduction device. | 11-25-2010 |
20100293930 | METHOD AND APPARATUS FOR AMMONIA FORMATION IN A CATALYTIC CONVERTER - An exhaust gas aftertreatment system for treating an engine-out exhaust gas feedstream of a spark-ignition direct-injection engine includes a multi-stage catalytic converter comprising a converter inlet, a converter outlet, and a substrate having a first end associated with the converter inlet and a second end associated with the converter outlet. The substrate further includes a multiplicity of flow passages between the first and second ends of the substrate, a first surface location corresponding to the first end of the substrate, and a second surface location corresponding to the second end of the substrate. A first washcoat stage is applied to the substrate at the first surface location corresponding to the first end of the substrate. A second washcoat stage is applied to the substrate at the second surface location corresponding to the second end of the substrate. The first and second washcoat stages include washcoats formulated to generate hydrogen and ammonia from the engine-out exhaust gas feedstream. An ammonia-selective catalytic reduction device is downstream of the first and second washcoat stages. | 11-25-2010 |
20110202253 | FUEL EFFICIENT AMMONIA GENERATION STRATEGY FOR LEAN-BURN ENGINES UTILIZING PASSIVE NH3-SCR FOR THE CONTROL OF NOX - A method and system for operating an ammonia generation cycle in an internal combustion engine and a connected aftertreatment system includes monitoring a parameter of engine operation, comparing the parameter of engine operation to a threshold delineating operation of the engine in one of a stoichiometric operation and rich operation, and operating the ammonia generation cycle based upon the comparing indicating the parameter of engine operation exceeding the threshold. | 08-18-2011 |
20110209467 | METHOD FOR SUPPLYING REDUCTANT TO AN AFTERTREATMENT SYSTEM - A method for supplying reductant into an exhaust gas feedstream for an internal combustion engine includes storing a fuel/reductant blend in the fuel storage and delivery system, separating the reductant from the fuel/reductant blend, storing the reductant in a reductant storage tank, and injecting the reductant into the exhaust gas feedstream upstream of the aftertreatment device. | 09-01-2011 |
20120055138 | METHODS FOR ENGINE EXHAUST NOX CONTROL USING NO OXIDATION IN THE ENGINE - A powertrain includes an internal combustion engine having a combustion chamber and an aftertreatment system. A method for reducing NOx emissions in the powertrain includes monitoring an actual exhaust gas feedstream ratio of NO | 03-08-2012 |
20120060472 | CATALYST MATERIALS FOR NOx OXIDATION IN AN EXHAUST AFTERTREATMENT SYSTEM THAT USES PASSIVE AMMONIA SCR - An exhaust aftertreatment system that receives an exhaust flow from a lean-burn engine and a method for treating the exhaust flow are described. The exhaust aftertreatment system may include a three-way-catalyst, an oxidation catalyst, and a NH | 03-15-2012 |
20120079813 | OPERATING METHODS FOR SELECTIVE CATALYTIC REDUCTION OF NOx - Where oxygenated hydrocarbons, such as ethanol, may be considered for use as a reductant to be added to diesel or gasoline engine exhaust for promoting the catalyzed reduction of NOx to N | 04-05-2012 |
20120311998 | SYSTEM AND METHOD FOR DETERMINING AN AMMONIA GENERATION RATE IN A THREE-WAY CATALYST - A system according to the principles of the present disclosure includes a rate determination module, a storage level determination module, and an air/fuel ratio control module. The rate determination module determines an ammonia generation rate in a three-way catalyst based on a reaction efficiency and a reactant level. The storage level determination module determines an ammonia storage level in a selective catalytic reduction (SCR) catalyst positioned downstream from the three-way catalyst based on the ammonia generation rate. The air/fuel ratio control module controls an air/fuel ratio of an engine based on the ammonia storage level. | 12-13-2012 |
20130025261 | SYSTEM AND METHOD FOR CONTROLLING AMMONIA LEVELS IN A SELECTIVE CATALYTIC REDUCTION CATALYST USING A NITROGEN OXIDE SENSOR - A system according to the principles of the present disclosure includes an air/fuel ratio determination module and an emission level determination module. The air/fuel ratio determination module determines an air/fuel ratio based on input from an air/fuel ratio sensor positioned downstream from a three-way catalyst that is positioned upstream from a selective catalytic reduction (SCR) catalyst. The emission level determination module selects one of a predetermined value and an input based on the air/fuel ratio. The input is received from a nitrogen oxide sensor positioned downstream from the three-way catalyst. The emission level determination module determines an ammonia level based on the one of the predetermined value and the input received from the nitrogen oxide sensor. | 01-31-2013 |
20130311065 | SYSTEM AND METHOD FOR CONTROLLING AN ENGINE BASED ON AMMONIA STORAGE IN MULTIPLE SELECTIVE CATALYTIC REDUCTION CATALYSTS - A system according to the principles of the present disclosure includes a storage estimation module and an air/fuel ratio control module. The storage estimation module estimates a first amount of ammonia stored in a first selective catalytic reduction (SCR) catalyst and estimates a second amount of ammonia stored in a second SCR catalyst. The air/fuel ratio control module controls an air/fuel ratio of an engine based on the first amount, the second amount, and a temperature of a substrate disposed in the second SCR catalyst. | 11-21-2013 |