A siloxane mitigation system for a machine system having an internal combustion engine includes a siloxane trap having a plurality of adsorbent cartridges fluidly in parallel with one another, an air precleaner fluidly connected to a trap housing inlet, and a blower structured to blow intake air to the siloxane trap to compensate for a pressure drop across the siloxane trap. A trap performance sensor of the siloxane mitigation system is structured for monitoring an exhaust pressure to indicate performance degradation of the siloxane mitigation system and activate an operator-perceptible alert.

An aftertreatment system for treating constituents of an exhaust gas produced by an engine includes a heater configured to selectively heat the exhaust gas entering the aftertreatment system. An aftertreatment component is disposed downstream of the heater. A gas sensor is disposed downstream of the heater and upstream of the aftertreatment component. The gas sensor comprises a sensing element, and a heating element configured to selectively heat the sensing element to an operating temperature of the sensing element.

A filtration assembly for removing particulate matter from exhaust gas produced by an engine, including: a first filter; a second filter positioned downstream of the first filter; and a valve including: a first ring defining a plurality of first openings, and a second ring defining a plurality of second openings, the second ring abutting the first ring. The valve is moveable between a closed position in which the plurality of first openings are misaligned with the plurality of second openings to prevent a fluid from flowing through the plurality of first and second openings, and an open position in which the second ring is rotated relative to the first ring such that the plurality of first openings are aligned with the plurality of second openings allowing the fluid to flow therethrough. A first end of the valve is positioned at an outlet of the first filter, and a second end of the valve is positioned at an inlet of the second filter. In the closed position of the valve, substantially all of the exhaust gas flows through the second filter, and in the open position of the valve, at least a portion of the exhaust gas flows through the valve and bypasses the second filter.

A method for detecting a dosing error of a reduction agent in a dosing module of an SCR catalytic converter system. The SCR catalytic converter system comprises the dosing module, which has a dosing valve and a flow valve as well as a delivery module with delivery pump. The SCR catalytic converter system, furthermore, has a return, in which a further flow valve is arranged. Said flow valve changes an effective cross-sectional area of the return. The method herein comprises the following steps: at the beginning, the dosing valve is closed (200). At a first pressure value (p.sub.1) in the system the delivery pump is switched off (201) and a measurement (202) of a first pressure rate (β.sub.RL.sup.dynamic) of the flow valve of the return subsequently takes place. Additional operation of the pump and the dosing valve occurs and a ratio of pressure rates is determined.

Provided is a method for diagnosing whether an oxidation catalyst has degraded, based on an output value from one diagnostic sensor with higher accuracy. When a ratio of nitrogen monoxide that is oxidized by a catalyst and discharged downstream of the catalyst as nitrogen dioxide, with respect to nitrogen monoxide contained in an exhaust gas supplied upstream of the catalyst in an exhaust path is defined as a NO conversion rate, a diagnostic sensor configured to output an electromotive force corresponding to the NO conversion rate as a diagnostic output is provided downstream of the catalyst in the exhaust path, and whether the catalyst has degraded beyond an acceptable limit is diagnosed by comparing the diagnostic output with a threshold value predetermined depending on a temperature of the catalyst.

A method to reduce NOx breakthrough and NH3 slip is provided when the SCR system is increasing in temperature and/or increasing exhaust gas mass flow. The method includes the steps of monitoring states of parameters of the exhaust gas upstream of an SCR catalyst where the states of parameters include at least one of the inlet temperature or the exhaust gas mass flow; identifying one of a temperature increase or an increased exhaust gas mass flow at the SCR inlet; identifying a new lower ammonia set-point or storage concentration for the SCR; and identifying the rate of NH3 consumption. The method further includes the step of determining an “intervening phase” a small dosage of DEF is continued during the intervening phase.

A heating system includes at least one electric heater disposed within a fluid flow system and a control device that is configured to determine a temperature of the at least one electric heater based on a model, at least one fluid flow system input, and at least one heater input. The at least one heater input includes at least one physical characteristic of the heating system, the at least one physical characteristic includes at least one of a resistance wire diameter, a heater insulation thickness, a heater sheath thickness, a conductivity, a specific heat and density of the material of the heater, an emissivity of the heater and the fluid flow pathway, and combinations thereof. The control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.

A method for NOx emission control during start of a vehicle comprising an exhaust aftertreatment system, an engine, and a NOx sensor is provided. The method includes determining a temperature of the NOx sensor; if the determined temperature of the NOx sensor is below a predetermined threshold, initiating heating of the NOx sensor, and performing a preventive action for delaying engine start until a determined temperature of the NOx sensor exceeds or is equal to the predetermined threshold.

A controller for controlling operation of an aftertreatment system that is configured to treat constituents of an exhaust gas produced by an engine, the aftertreatment system including a selective catalytic reduction (SCR) catalyst, the controller configured to: generate a short-term cumulative degradation estimate of the SCR catalyst corresponding to reversible degradation of the SCR catalyst due to sulfur and/or hydrocarbons based on a SCR catalyst temperature parameter; generate a long-term cumulative degradation estimate of the SCR catalyst corresponding to thermal aging of the SCR catalyst based on the SCR catalyst temperature parameter; generate a combined degradation estimate of the SCR catalyst based on the short-term cumulative degradation estimate and the long-term cumulative degradation estimate; and adjust an amount of reductant and/or an amount of hydrocarbons inserted into the aftertreatment system based on the combined degradation estimate of the SCR catalyst.

A method includes calculating whether a quantity of the PMs accumulated in a PF is at or above a risk level at which damage to the PF is caused when reproducing the PF, calculating a driving condition index by accumulating a weighting factor for a driving condition under which there is a likelihood of causing the damage to the PF, when the amount of accumulated PMs is at or above the risk level; calculating a temperature index in accordance with a temperature of the PF and a PM index in accordance with the quantity of the accumulated PMs when the quantity of the accumulated PMs is at or above the risk level; calculating a degradation condition index considering the driving condition index, the temperature of the PF, and the quantity of accumulated PMs; and changing a reproduction periodicity of the PF according to the degradation condition index.