Patent application number | Description | Published |
20080260610 | REVERSE PLATINUM GROUP METAL ZONED LEAN NOx TRAP SYSTEM AND METHOD OF USE - The invention, in at least one embodiment, relates to a reverse platinum group metal zoned lean NO | 10-23-2008 |
20080289318 | Low Temperature Emission Control - A method of controlling an engine having a lean NOx trap in the exhaust is described. The method comprises during a first mode, at a first temperature, storing NOx at a lean condition and then purging stored NOx from the NOx trap at a rich condition without concurrently supplying oxygen to the trap during the purging and during a second mode, at a second, lower temperature, storing NOx at a lean condition and then purging stored NOx from the NOx, where an exothermic reaction is generated to temporarily raise the temperature of the trap by supplying oxygen and reductants with an overall rich mixture to the trap during the purging. | 11-27-2008 |
20090260349 | AIR-INJECTION SYSTEM TO IMPROVE EFFECTIVENESS OF SELECTIVE CATALYTIC REDUCTION CATALYST FOR GASOLINE ENGINES - Embodiments are described to improve the durability of a lean NO | 10-22-2009 |
20090266063 | SELECTIVE CATALYTIC REDUCTION CATALYST SYSTEM WITH EXPANDED TEMPERATURE WINDOW - According to one embodiment of the present invention a selective reduction catalyst system with a broad temperature window for lean-burn gasoline and diesel engines is disclosed. The system includes a first and second zone, wherein the first zone is composed of an iron SCR catalyst and a second zone is composed of a copper SCR catalyst, and wherein the second zone is positioned downstream of the first zone. In another embodiment, a small copper SCR catalyst is placed in front of a second zone composed of an iron SCR catalyst and a third zone composed of a copper SCR catalyst, wherein the volume of the first copper SCR catalyst is a fraction of the volume of the second copper SCR catalyst. In yet another embodiment, a diverter valve would be included in the system to eliminate any NO | 10-29-2009 |
20100132335 | SCR EMISSIONS-CONTROL SYSTEM - An emissions-control system of a vehicle is provided, having an LNT disposed in an exhaust system of the vehicle, downstream of the engine, an SCR device disposed downstream of the LNT, and a controller. The controller is operatively coupled to the engine and configured to cause the engine to provide a reducing exhaust to the LNT at least during an enrichment interval, the enrichment interval including an enrichment subinterval beginning after a sensor indicates rich breakthrough, and further configured to adjust the duration and/or the level of enrichment for the enrichment subinterval in response to an ageing of the LNT. In this way, it is possible to modify LNT regeneration based on catalyst performance and thereby generate sufficient ammonia for improved operation of the SCR device. | 06-03-2010 |
20100313548 | Emission Control System with an Optimized Reductant Injection Model - According to at least one aspect of the present invention, there is provided an emission control system which includes a reductant injector injecting a pre-determined amount of a reductant into a vehicle exhaust passage, and sensors measuring an exhaust space velocity, a selective catalytic reduction (SCR) catalyst temperature, and a before-SCR nitrogen oxide (NO | 12-16-2010 |
20130312391 | EXHAUST AIR INJECTION - Embodiments for controlling exhaust oxygen concentration are provided. In one example, an engine method comprises operating the engine with lean combustion, and when exhaust oxygen concentration is below a threshold, injecting air into an exhaust passage between a first emission control device and an SCR device. In this way, excess emissions may be converted while operating with lean combustion. | 11-28-2013 |
20140039778 | NOX CONTROL DURING CYLINDER DEACTIVATION - Methods and systems are provided for improving engine exhaust emissions while enabling exhaust catalyst regeneration following an engine lean event. Prior to a VDE event, or prior to an engine idle-stop, ammonia is produced and stored on an exhaust underbody SCR catalyst. Then, during the engine restart after the VDE mode or the idle-stop, the stored ammonia is used to treat exhaust NOx species while an upstream exhaust underbody three-way catalyst is regenerated. | 02-06-2014 |
20140039781 | NOX CONTROL DURING ENGINE IDLE-STOP OPERATIONS - Methods and systems are provided for improving engine exhaust emissions while enabling exhaust catalyst regeneration following an engine lean event. Prior to a VDE event, or prior to an engine idle-stop, ammonia is produced and stored on an exhaust underbody SCR catalyst. Then, during the engine restart after the VDE mode or the idle-stop, the stored ammonia is used to treat exhaust NOx species while an upstream exhaust underbody three-way catalyst is regenerated. | 02-06-2014 |
20140311126 | AIR-INJECTION SYSTEM TO IMPROVE EFFECTIVENESS OF SELECTIVE CATALYTIC REDUCTION CATALYST - Embodiments are described to improve the durability of a lean NO | 10-23-2014 |
20150027107 | NOX CONTROL DURING ENGINE IDLE-STOP OPERATIONS - Methods and systems are provided for improving engine exhaust emissions while enabling exhaust catalyst regeneration following an engine lean event. Prior to a VDE event, or prior to an engine idle-stop, ammonia is produced and stored on an exhaust underbody SCR catalyst. Then, during the engine restart after the VDE mode or the idle-stop, the stored ammonia is used to treat exhaust NOx species while an upstream exhaust underbody three-way catalyst is regenerated. | 01-29-2015 |