| Patent application number | Description | Published |
|---|
| 20080302092 | NOX ADSORBER CATALYST AND SYSTEM THEREFOR - A NOx adsorber catalyst may comprise a housing defining an inlet configured to receive exhaust gas produced by an internal combustion engine, an outlet and a chamber between the inlet and the outlet. A NOx adsorber element may be positioned in the chamber adjacent to the inlet. The NOx adsorber element may be configured to trap NOx in the exhaust gas during lean fuel operation of the engine, and to release the trapped NOx and reduce the released NOx to nitrogen during rich fuel operation of the engine. A hydrocarbon trap may be positioned in the chamber between the NOx adsorber element and the outlet. The hydrocarbon trap may be configured to trap hydrocarbons that travel through the NOx adsorber element during the rich fuel operation of the engine. The trapped hydrocarbons may be oxidized by oxygen present in the exhaust gas during lean fuel operation following rich fuel operation. | 12-11-2008 |
| 20090272099 | APPARATUS, SYSTEM, AND METHOD FOR DETERMINING THE DEGRADATION OF AN SCR CATALYST - According to one representative embodiment, an apparatus for determining the degradation of a selective catalytic reduction (SCR) catalyst of an engine exhaust aftertreatment system includes a system properties module configured to store at least one system dynamics property value of the exhaust system at a first time and receive the at least one system dynamics property value of the exhaust aftertreatment system at a second time subsequent to the first time. The apparatus also includes a system dynamics module configured to determine a storage capacity of the SCR catalyst based on a comparison between the at least one system dynamic property value at the first time and the at least one system dynamic property value at the second time. Additionally, the apparatus includes an SCR catalyst degradation factor module configured to determine an SCR catalyst degradation factor based at least partially on the storage capacity of the SCR catalyst. | 11-05-2009 |
| 20100024390 | APPARATUS, SYSTEM, AND METHOD FOR REDUCING NOx EMISSIONS ON AN SCR CATALYST - According to one representative embodiment, an apparatus for reducing NO | 02-04-2010 |
| 20110047964 | METHODS, SYSTEMS, AND APPARATUSES OF SCR DIAGNOSTICS - One embodiment is a method including operating an SCR system at a plurality of commanded ammonia to NOx input ratios, providing a plurality of data indicating NOx output from the SCR system for the plurality of commanded ammonia to NOx input ratios, and evaluating the plurality of data to diagnose the SCR system. Additional embodiment are methods, systems, and apparatuses including SCR diagnostics. Further embodiments, forms, objects, features, advantages, aspects, and benefits shall become apparent from the following description and drawings. | 03-03-2011 |
| 20110047970 | HIGH EFFICIENCY NOx REDUCTION SYSTEM AND METHOD - An exhaust gas stream aftertreatment system and method achieves high efficiency NOx reduction in exhaust gas emissions by arranging a selective catalytic reduction (SCR) catalyst element upstream from a NOx adsorber catalyst. In an exemplary embodiment, a reductant is introduced into the exhaust gas stream, exposing the exhaust gas stream containing the reductant to a selective catalytic reduction (SCR) catalyst element, and exposing the exhaust gas stream that was exposed to the SCR catalyst element to a NOx adsorber catalyst element. The NOx adsorber catalyst element can be regenerated by temporarily reducing an oxygen concentration in an exhaust gas stream to reduce the λ of the exhaust gas stream. While the oxygen concentration is reduced, reductant is introduced into the exhaust gas stream at a rate that achieves a fuel-rich condition, and the fuel rich exhaust stream is exposed to the NOx adsorber catalyst element. | 03-03-2011 |
| 20110113756 | System, method and apparatus for fuel injector diagnostics - A method includes providing a system having a fluid flow, a fuel injector and an oxygen sensor disposed in the fluid flow, where the oxygen sensor is downstream of the fuel injector. The method includes determining a first air fuel ratio, changing an injection rate of the fuel injector and determining a second air fuel ratio, and determining a fault value for the fuel injector from the first air fuel ratio and the second air fuel ratio. The method further includes determining the fault value for the fuel injector by determining a difference between the first air fuel ratio and the second air fuel ratio, and by determining that the fault value is positive in response to the difference being lower than a passing threshold value. The method includes changing injection rates of the fuel injector for specified periods of time short enough to significant disruption of system temperatures. | 05-19-2011 |
| 20110139136 | TECHNIQUES FOR ENHANCING AFTERTREATMENT REGENERATION CAPABILITY - A system is provided for enhancing aftertreatment regeneration capability. The system includes an internal combustion engine producing an exhaust gas stream and an aftertreatment component that treats the exhaust gas stream, where the aftertreatment component includes a desired inlet exhaust gas temperature. The system includes an exhaust gas pressure device that modulates an exhaust pressure value, and a fuel injection system that provides a post-injection event. The system includes a controller that provides an exhaust pressure command and a fuel injection command in response to determining that a temperature of the exhaust gas stream is lower than the desired inlet exhaust gas temperature. The exhaust gas pressure device is responsive to the exhaust pressure command and the fuel injection system is responsive to the fuel injection command. | 06-16-2011 |
| 20110146270 | TECHNIQUES FOR OPTIMIZING ENGINE OPERATIONS DURING AFTERTREATMENT REGENERATION - A system is described for producing an elevated exhaust temperature and reduced NO | 06-23-2011 |
