A reductant injecting device, including: a honeycomb structure including: a pillar shaped honeycomb structure portion having partition wall that defines a plurality of cells each extending from a fluid inflow end face to a fluid outflow end face; and at least one pair of electrode portions arranged on a side surface of the honeycomb structure portion; an outer cylinder having an inlet side end portion and an outlet side end portion, the inlet side end portion comprising a carrier gas introduction port being configured to introduce a carrier gas, the outlet side end portion comprising an injection port being configured to inject ammonia; a urea sprayer arranged at one end of the outer cylinder; and a spray direction switcher configured to be able to switch a spray direction of the aqueous urea solution.

A control apparatus is applied to an internal combustion engine where an EHC and a filter are arranged in this sequence from an upstream side. The control apparatus performs a regeneration process for removing particulate matter deposited in the filter through oxidation, and a recovery process for raising the temperature of exhaust gas to a temperature higher than in the case of the regeneration process and removing the particulate matter deposited at a front end portion of the EHC through oxidation when it is determined that the insulation resistance of the EHC is equal to or lower than a prescribed value. The control apparatus performs the regeneration process and then the recovery process when it is determined that the insulation resistance is equal to or lower than the prescribed value and the deposition amount of the particulate matter in the filter is equal to or larger than a prescribed amount.

Methods and systems are provided for maintaining a temperature of exhaust gases of an engine within a temperature range at which catalytic conversion is most efficient. In one example, a method for controlling a temperature of exhaust gases entering a Selective Catalytic Reduction (SCR) system for an engine comprises delivering pressurized air into the exhaust gases upstream of the SCR system, the pressurized air cooled by an air cooler; and adjusting a degree of pressurization by adjusting operation of a turbocharger pressurizing the pressurized air. In one embodiment, the air cooler may be a charge air cooler of a primary turbocharger of the engine, which may flow pressurized air both to the engine and to the SCR system. In other embodiments, the air may be pressurized by an air pump or a secondary dilution turbocharger, and cooled by a secondary charge air cooler.

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.

An engine control module (ECM) may obtain information concerning a speed of an engine, information concerning an exhaust gas temperature, information concerning an engine airflow rate, information concerning a pressure of an intake manifold associated with the engine, and information concerning a requested amount of engine braking power. The ECM may cause one or more components of a variable geometry turbocharger (VGT) to adjust based on the information concerning the speed of the engine, the information concerning the exhaust gas temperature, and the information concerning the engine airflow rate. Additionally, or alternatively, the ECM may cause the one or more components of the VGT to adjust based on the information concerning the pressure of the intake manifold associated with the engine and the information concerning the requested amount of engine braking power.

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.

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 controller for controlling regeneration of a selective catalytic reduction (SCR) catalyst of an aftertreatment system is configured to cause increase in a SCR catalyst temperature of the SCR catalyst to a first regeneration temperature, the first regeneration temperature being lower than a high regeneration temperature that is equal to or greater than 500 degrees Celsius. The controller is configured to determine an amount of ammonia slip downstream of the SCR catalyst; and cause an increase in the SCR catalyst temperature to a second regeneration temperature greater than the first regeneration temperature but lower than the high regeneration temperature based on the determined amount of ammonia slip.