Abstract: Method for controlling and detecting ammonium nitrate and/or ammonium nitrite poisoning within selective catalytic reduction (SCR) devices and systems incorporating the same are provided. Methods can include detecting a SCR inlet exhaust gas NO2:NOx ratio above a poisoning NOx flux threshold, detecting a SCR temperature below a poisoning temperature threshold, and determining SCR catalyst poisoning. Methods can further include performing a SCR catalyst cleaning strategy, wherein the SCR cleaning strategy comprises heating the SCR catalyst composition to a temperature above the poisoning temperature threshold. Cleaning strategies can including utilizing a heater, implementing a post-injection, after-injection, and/or auxiliary injection engine strategy wherein the engine is configured to supply exhaust gas to the SCR.

Abstract: Method for controlling and detecting ammonium nitrate and/or ammonium nitrite poisoning within selective catalytic reduction (SCR) devices and systems incorporating the same are provided. Methods can include detecting a SCR inlet exhaust gas NO2:NOx ratio above a poisoning NOx flux threshold, detecting a SCR temperature below a poisoning temperature threshold, and determining SCR catalyst poisoning. Methods can further include performing a SCR catalyst cleaning strategy, wherein the SCR cleaning strategy comprises heating the SCR catalyst composition to a temperature above the poisoning temperature threshold. Cleaning strategies can including utilizing a heater, implementing a post-injection, after-injection, and/or auxiliary injection engine strategy wherein the engine is configured to supply exhaust gas to the SCR.

Abstract: A mixing chamber for an exhaust system is disclosed. The mixing chamber includes a tapering cross sectional area perpendicular to a longitudinal axis of the mixing chamber. The mixing chamber includes a first end having a first cross sectional area and a second end having a second cross sectional area. The second cross sectional area is less than the first cross sectional area. The second end is configured to receive an injector. The mixing chamber includes a first exhaust conduit fluidly connected to the first end of the mixing chamber and defining a first exhaust gas flow path into the mixing chamber substantially perpendicular to the longitudinal axis. The mixing chamber also includes a second exhaust conduit fluidly connected to the first end of the mixing chamber and defining a second exhaust gas flow path out of the mixing chamber substantially in the direction of the longitudinal axis.

Abstract: A mixing chamber for an exhaust system is disclosed. The mixing chamber includes a tapering cross sectional area perpendicular to a longitudinal axis of the mixing chamber. The mixing chamber includes a first end having a first cross sectional area and a second end having a second cross sectional area. The second cross sectional area is less than the first cross sectional area. The second end is configured to receive an injector. The mixing chamber includes a first exhaust conduit fluidly connected to the first end of the mixing chamber and defining a first exhaust gas flow path into the mixing chamber substantially perpendicular to the longitudinal axis. The mixing chamber also includes a second exhaust conduit fluidly connected to the first end of the mixing chamber and defining a second exhaust gas flow path out of the mixing chamber substantially in the direction of the longitudinal axis.

Abstract: A hydrocarbon selective catalytic reduction (HC-SCR) catalyst is regenerated using a nitrogen-based reductant agent. The HC-SCR catalyst is in communication with a power system such as an internal combustion engine and receives exhaust gasses from the internal combustion engine. Sulfur in the exhaust gasses may deactivate the HC-SCR catalyst by sulfur oxides forming thereon. To remove the sulfur oxides, a nitrogen-based reductant agent is introduced to the exhaust gasses. The nitrogen-based reductant agent decomposes to nitrogen oxides and hydrogen. The hydrogen reacts with the sulfur oxides to form hydrogen sulfides thereby removing the sulfur oxides from the HC-SCR catalyst.

Abstract: A method of controlling a power system including an engine and an exhaust treatment system having an exhaust treatment device is disclosed. The method includes determining a catalyst parameter indicative of a conversion efficiency of the exhaust treatment device. The method further includes determining a weighted index based on the catalyst parameter. The method further includes determining a plurality of first index values. In the method, each first index value of the plurality of first index values is predicted as a function of a corresponding respective aftertreatment control strategy. The method further includes selecting an aftertreatment control strategy based on a comparison between the weighted index and each first index value of the plurality of first index values. In the method, the selected aftertreatment control strategy changes the catalyst parameter.

Abstract: A hydrocarbon selective catalytic reduction (HC-SCR) catalyst is regenerated using a nitrogen-based reductant agent. The HC-SCR catalyst is in communication with a power system such as an internal combustion engine and receives exhaust gasses from the internal combustion engine. Sulfur in the exhaust gasses may deactivate the HC-SCR catalyst by sulfur oxides forming thereon. To remove the sulfur oxides, a nitrogen-based reductant agent is introduced to the exhaust gasses. The nitrogen-based reductant agent decomposes to nitrogen oxides and hydrogen. The hydrogen reacts with the sulfur oxides to form hydrogen sulfides thereby removing the sulfur oxides from the HC-SCR catalyst.

Abstract: A hydrocarbon selective catalytic reduction (HC-SCR) catalyst is regenerated using a nitrogen-based reductant agent. The HC-SCR catalyst is in communication with a power system such as an internal combustion engine and receives exhaust gasses from the internal combustion engine. Sulfur in the exhaust gasses may deactivate the HC-SCR catalyst by sulfur oxides forming thereon. To remove the sulfur oxides, a nitrogen-based reductant agent is introduced to the exhaust gasses. The nitrogen-based reductant agent decomposes to nitrogen oxides and hydrogen. The hydrogen reacts with the sulfur oxides to form hydrogen sulfides thereby removing the sulfur oxides from the HC-SCR catalyst.

Abstract: A method of controlling a power system including an engine and an exhaust treatment system having an exhaust treatment device is disclosed. The method includes determining a catalyst parameter indicative of a conversion efficiency of the exhaust treatment device. The method further includes determining a weighted index based on the catalyst parameter. The method further includes determining a plurality of first index values. In the method, each first index value of the plurality of first index values is predicted as a function of a corresponding respective aftertreatment control strategy. The method further includes selecting an aftertreatment control strategy based on a comparison between the weighted index and each first index value of the plurality of first index values. In the method, the selected aftertreatment control strategy changes the catalyst parameter.

Abstract: An exhaust system for an internal combustion engine includes an exhaust filter positioned within an exhaust conduit, and having a first and a second NOx sensing mechanism positioned upstream and downstream the exhaust filter. An electronic control unit is coupled with the NOx sensing mechanisms and generates a signal indicative of a soot loading state of the exhaust filter responsive to a difference in species composition of the sensed NOx upstream and downstream the exhaust filter. Related methodology and control strategy are also disclosed.

Abstract: An exhaust treatment system is provided including: a selective catalyst reduction (SCR) unit; a reducing agent dispensing unit configured to introduce a reducing agent into the exhaust; a first NOX sensor upstream of the SCR unit; a second NOX sensor at a location downstream of the SCR unit; a first temperature sensor at a location upstream of where the reducing agent is introduced into the exhaust; a second temperature sensor at a location downstream of where the reducing agent is introduced into the exhaust and upstream of the SCR unit; and a controller configured to determine a reductant quality indicator according to a NOX differential between the first NOX sensor and the second NOX sensor relative to a predicted NOX differential and a temperature differential between the first temperature sensor and the second temperature sensor relative to a predicted temperature differential.

Abstract: An exhaust system for use with a combustion engine is disclosed. The exhaust system may have a passage connected to receive exhaust from the combustion engine, and a cooling device located external to the passage to create a thermal gradient across a flow area of the passage that causes particulates within the exhaust to agglomerate on a wall of the passage. The exhaust system may also have a filtration device located to separate agglomerated particulates from the exhaust.

Abstract: An exhaust aftertreatment system for an engine is disclosed. The exhaust aftertreatment system including a first exhaust passage, an SCR catalyst disposed in the first exhaust passage, a second exhaust passage parallel with the first exhaust passage and fluidly coupled to the first exhaust passage upstream of the SCR catalyst and a container disposed in the second exhaust passage, the container configured to hold a volume of urea and to direct exhaust from the second exhaust passage through the volume of urea in the container.

Abstract: An exhaust treatment control system includes a controller configured to determine a value representative of a NO2 concentration associated with an exhaust gas upstream of a selective catalytic reduction (SCR) catalyst, and determine a value representative of a NO concentration associated with the exhaust gas upstream of the SCR catalyst. The controller can also be configured to transmit a signal to at least partially control an injection of a hydrocarbon into the exhaust gas, wherein the hydrocarbon injection can occur upstream of an oxidation catalyst to at least partially decrease the NO2 concentration of the exhaust gas downstream of the oxidation catalyst, and wherein the oxidation catalyst can be located upstream of the SCR catalyst.

Abstract: An exhaust aftertreatment system for an engine is disclosed. The exhaust aftertreatment system including a first exhaust passage, an SCR catalyst disposed in the first exhaust passage, a second exhaust passage parallel with the first exhaust passage and fluidly coupled to the first exhaust passage upstream of the SCR catalyst and a container disposed in the second exhaust passage, the container configured to hold a volume of urea and to direct exhaust from the second exhaust passage through the volume of urea in the container.

Abstract: An exhaust system for use with a combustion engine is disclosed. The exhaust system may have a passage connected to receive exhaust from the combustion engine, and a cooling device located external to the passage to create a thermal gradient across a flow area of the passage that causes particulates within the exhaust to agglomerate on a wall of the passage. The exhaust system may also have a filtration device located to separate agglomerated particulates from the exhaust.

Abstract: An exhaust treatment control system includes a controller configured to determine a value representative of a NO2 concentration associated with an exhaust gas upstream of a selective catalytic reduction (SCR) catalyst, and determine a value representative of a NO concentration associated with the exhaust gas upstream of the SCR catalyst. The controller can also be configured to transmit a signal to at least partially control an injection of a hydrocarbon into the exhaust gas, wherein the hydrocarbon injection can occur upstream of an oxidation catalyst to at least partially decrease the NO2 concentration of the exhaust gas downstream of the oxidation catalyst, and wherein the oxidation catalyst can be located upstream of the SCR catalyst.