The present disclosure is directed to a system for treating an exhaust gas stream from an engine, which includes a diesel oxidation catalyst (DOC) located downstream of the engine and adapted for oxidation of hydrocarbons and carbon monoxide, an injector adapted for the addition of a reductant to the exhaust gas stream located downstream of the DOC, a catalyzed soot filter (CSF) located downstream of the injector, and a selective catalytic reduction component adapted for the oxidation of nitrogen oxides located downstream of the CSF. The CSF is adapted for oxidizing hydrocarbons and includes a selective oxidation catalyst composition on a filter with high selectivity ratio for hydrocarbon oxidation:ammonia oxidation (e.g., at least 0.6).

A thermoelectric power generation system includes a first flow path, along which a first fluid flows, a second flow path, along which a second fluid having a lower temperature than the first fluid flows, a thermoelectric module arranged between the first flow path and the second flow path, and a controller that switches between a power generation mode and a heating mode. In the power generation mode, the thermoelectric module is caused to generate electric power, based on a difference between a temperature of the first fluid and a temperature of the second fluid. In the heating mode, a first surface of the thermoelectric module is heated using the Peltier effect caused by supplying electric power to the thermoelectric module. A distance between the first surface and the first flow path is shorter than a distance between the first surface and the second flow path.

An engine system includes an engine having piston-cylinder arrangements communicating with an intake manifold and an exhaust manifold, a turbocharger including a turbine in communication with the exhaust manifold and a compressor driven by the turbine and in communication with the intake manifold, and an EGR system including an EGR pump having an inlet side in communication with the exhaust manifold and an outlet side in communication with the intake manifold, and an EGR cooler that cools exhaust gas flowing through the EGR system. The engine system also includes a controller operably connected with the EGR pump and configured to selectively operate the EGR pump in a forward mode to flow exhaust gas therethrough in a first direction and in a reverse mode to substantially prevent flow of exhaust gas therethrough or provide a non-exhaust air flow therethrough in a second direction.

Various methods and systems are provided for controlling air flow through an engine by adjusting an electric turbocharger of a vehicle. In one embodiment, a system for a vehicle comprises an electric turbocharger comprising a compressor, an exhaust turbine coupled to the compressor via a shaft, and an electric machine mechanically coupled to the shaft; and a controller including a processor and instructions stored on a non-transient memory of the controller that, when executed, cause the controller to: adjust an amount of power provided to or extracted from the shaft by the electric machine based on at least one of a speed of the electric turbocharger, a cylinder pressure, and an exhaust gas temperature. By adjusting the amount of power provided to or extracted from the electric machine, the exhaust gas temperature and the speed of the electric turbocharger may be efficiently maintained within a desired operating range.

A modular exhaust subsystem for purifying an exhaust gas feedstream of a compression-ignition internal combustion engine upstream of a base exhaust aftertreatment system includes a selective catalytic reduction (SCR) catalyst, and a first exhaust gas sensor and a first temperature sensor that are arranged to monitor the SCR catalyst. A reductant delivery system is arranged to inject a reductant upstream of the SCR catalyst. A controller is in communication with an engine-out exhaust gas sensor, a second exhaust gas sensor and a second temperature sensor that are arranged to monitor the base exhaust aftertreatment system. The controller controls the reductant delivery system to inject the reductant into the exhaust gas feedstream upstream of the SCR catalyst based upon inputs from the first and second exhaust gas sensors, the engine-out exhaust gas sensor, and the first and second temperature sensors.

A control system is provided for a diesel particulate filter (DPF) system of a diesel engine configured for operation in an off-highway vehicle. The control system includes a controller configured to receive a signal corresponding to a fill state of the DPF being at or above a first threshold. The controller is configured to selectively induce a parasitic load on the diesel engine to increase an operating temperature of the engine in response to receiving the signal.

The present disclosure describes methods for evaluating ammonia storage capacity of a close-coupled SCR unit while remaining compliant with prescribed emissions limits, methods of controlling an emission aftertreatment system including multiple SCR units and emission management systems for a vehicle including an internal combustion engine and an emission aftertreatment system that includes two or more SCR units.

An apparatus for use with a combustion apparatus and an associated Selective Catalytic Reduction (‘SCR’) device, comprises a temperature sensing device configured to measure the temperature of an exhaust from the combustion apparatus; and an injection unit configured to inject hydrogen into a feed of oxidizer to the combustion apparatus. An amount of hydrogen is added to an oxidiser feed of the combustion apparatus sufficient to reach a temperature in the exhaust of at least about 270° C.

Systems, methods, and apparatuses are provided for increasing exhaust gas temperature. A system includes a valve and a controller coupled to the valve. The controller is structured to determine that a plurality of cylinders of an engine are active; compare an exhaust aftertreatment temperature to an exhaust aftertreatment temperature setpoint; and in response to the comparison, adjust an effective flow area for exhaust gas from the plurality of cylinders of the engine to increase an exhaust gas temperature.

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.