Abstract: A method of treating exhaust gas from an internal combustion engine as the exhaust gas passes through an exhaust gas pathway includes injecting reductant into the exhaust gas pathway with a reductant injector, filtering particulate matter from the exhaust gas with a first treatment element located downstream of the reductant injector, oxidizing soot on the first treatment element with ozone, and converting nitrogen oxides (NOx) from the exhaust gas with a second treatment element located downstream of the reductant injector.

Abstract: An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine, a first treatment element positioned within the exhaust gas pathway, a first injector configured to introduce a first reductant into the exhaust gas pathway upstream of the first treatment element, a second injector configured to introduce a second reductant into the exhaust gas pathway downstream of the first treatment element, a second treatment element positioned within the exhaust gas pathway downstream of the second injector, the second treatment element including a SCR element, and a controller configured to periodically initiate a desulfuring regeneration cycle by increasing a concentration of hydrocarbons in the exhaust gas and increasing the flow of the first reductant through the first injector to oxidize sulfur contamination in the first treatment element at temperatures between 400 and 500 degrees Celsius.

Abstract: An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine, a first treatment element positioned within the exhaust gas pathway, the first treatment element including a selective catalytic reduction (SCR) element, a first injector configured to selectively introduce ammonia gas into the exhaust gas pathway upstream of the first treatment element, a second injector configured to introduce diesel exhaust fluid into the exhaust gas pathway downstream of the first treatment element, and a second treatment element positioned within the exhaust gas pathway downstream of the second injector, the second treatment element including a SCR element.

Abstract: One or more techniques and/or systems are disclosed for controlling exhaust heating to reduce engine out NOx emission. A heater is used for exhaust temperature control of an exhaust system and is activated at a non-active selective catalytic reduction (SCR) system temperature. One or more exhaust air flow bypasses are controlled during operation of the heater and heating of an exhaust air flow is maintained by the heater prior to activation of the SCR system.

Abstract: A method of treating exhaust gas from an internal combustion engine as the exhaust gas passes through an exhaust gas pathway includes injecting reductant into the exhaust gas pathway with a reductant injector, filtering particulate matter from the exhaust gas with a first treatment element located downstream of the reductant injector, oxidizing soot on the first treatment element with ozone, and converting nitrogen oxides (NOx) from the exhaust gas with a second treatment element located downstream of the reductant injector.

Abstract: An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine, a first treatment element positioned within the exhaust gas pathway, a first injector configured to introduce a first reductant into the exhaust gas pathway upstream of the first treatment element, a second injector configured to introduce a second reductant into the exhaust gas pathway downstream of the first treatment element, a second treatment element positioned within the exhaust gas pathway downstream of the second injector, the second treatment element including a SCR element, and a controller configured to periodically initiate a desulfuring regeneration cycle by increasing a concentration of hydrocarbons in the exhaust gas and increasing the flow of the first reductant through the first injector to oxidize sulfur contamination in the first treatment element at temperatures between 400 and 500 degrees Celsius.

Abstract: An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine, a first injector configured to selectively introduce a first reductant into the exhaust gas pathway in response to a sensed temperature of the exhaust gas being within a predetermined temperature range, and a first treatment element positioned within the exhaust gas pathway downstream of the first injector. The first treatment element includes a selective catalytic reduction (SCR) layer, a porous filter substrate, and a precious metal catalyst layer. The system also includes a second injector configured to introduce a second reductant into the exhaust gas pathway downstream of the first treatment element and a second treatment element positioned within the exhaust gas pathway downstream of the second injector. The second treatment element includes a SCR element.

Abstract: An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine, a first treatment element positioned within the exhaust gas pathway, the first treatment element including a selective catalytic reduction (SCR) element, a first injector configured to selectively introduce ammonia gas into the exhaust gas pathway upstream of the first treatment element, a second injector configured to introduce diesel exhaust fluid into the exhaust gas pathway downstream of the first treatment element, and a second treatment element positioned within the exhaust gas pathway downstream of the second injector, the second treatment element including a SCR element.

Abstract: An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine and a first treatment element positioned within the exhaust gas pathway such that the first treatment element is close coupled to the engine. The first treatment element includes a NOx storage element. A first injector is configured to selectively introduce a first reductant into the exhaust gas pathway upstream of the first treatment element, and a second injector is configured to introduce a second reductant into the exhaust gas pathway downstream of the first treatment element. The system includes a second treatment element positioned within the exhaust gas pathway downstream of the second injector, and the second treatment element includes a selective catalytic reduction (SCR) element.

Abstract: An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust from the engine, a diesel particulate filter (DPF) element positioned in the exhaust gas pathway to capture particulate matter from the exhaust, and a regenerator operable to increase a temperature of the exhaust that passes through the DPF element. The system also includes a controller configured to selectively operate the exhaust gas treatment system in a first mode in which the regenerator is inactive such that a temperature of the exhaust is within a first range, a second mode in which the regenerator is activated to increase the temperature of the exhaust to a first target temperature beyond the first range, and a third mode in which the regenerator is activated to increase the temperature of the exhaust to a second target temperature greater than the first temperature.

Abstract: An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine, a first injector configured to selectively introduce a first reductant into the exhaust gas pathway in response to a sensed temperature of the exhaust gas being within a predetermined temperature range, and a first treatment element positioned within the exhaust gas pathway downstream of the first injector. The first treatment element includes a selective catalytic reduction (SCR) layer, a porous filter substrate, and a precious metal catalyst layer. The system also includes a second injector configured to introduce a second reductant into the exhaust gas pathway downstream of the first treatment element and a second treatment element positioned within the exhaust gas pathway downstream of the second injector. The second treatment element includes a SCR element.

Abstract: An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine and a first treatment element positioned within the exhaust gas pathway such that the first treatment element is close coupled to the engine. The first treatment element includes a NOx storage element. A first injector is configured to selectively introduce a first reductant into the exhaust gas pathway upstream of the first treatment element, and a second injector is configured to introduce a second reductant into the exhaust gas pathway downstream of the first treatment element. The system includes a second treatment element positioned within the exhaust gas pathway downstream of the second injector, and the second treatment element includes a selective catalytic reduction (SCR) element.

Abstract: An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust from the engine, a diesel particulate filter (DPF) element positioned in the exhaust gas pathway to capture particulate matter from the exhaust, and a regenerator operable to increase a temperature of the exhaust that passes through the DPF element. The system also includes a controller configured to selectively operate the exhaust gas treatment system in a first mode in which the regenerator is inactive such that a temperature of the exhaust is within a first range, a second mode in which the regenerator is activated to increase the temperature of the exhaust to a first target temperature beyond the first range, and a third mode in which the regenerator is activated to increase the temperature of the exhaust to a second target temperature greater than the first temperature.

Abstract: An exhaust gas treatment system for an internal combustion engine with an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine. The system includes a heater operable to heat the exhaust gas as it passes through the exhaust gas pathway, an injector configured to inject reductant into the exhaust gas pathway, a first treatment element positioned in the exhaust gas pathway downstream of the heater and the injector, and a second treatment element positioned in the exhaust gas pathway downstream of the first treatment element. At least one of the first treatment element or the second treatment element includes a selective catalytic reduction (SCR) element, and the exhaust gas treatment system does not include a precious metal catalyst upstream of the first treatment element.