Systems and methods for treated exhaust gas recirculation (EGR) for an internal combustion engine are disclosed. The internal combustion engine has an exhaust manifold discharging exhaust gas and an intake manifold receiving forced air from a compressor. One or more exhaust treatment devices treat the exhaust gas and produce a treated exhaust gas. The EGR system includes an EGR line downstream of the one or more exhaust treatment devices and connected to the engine intake line downstream of the compressor, wherein the treated EGR line recirculates the treated exhaust gas to the intake manifold of the engine without passing through the compressor.

One embodiment is a system comprising an engine including a dedicated EGR cylinder configured to provide EGR to the engine via an EGR loop, a non-dedicated cylinder, a plurality of injectors, an ignition system including a plurality of spark plugs, an intake throttle, and an electronic control system. The electronic control system is configured to control combustion during transient operation of the engine by determining one or more combustion control parameters compensating for variation of one or more of inert matter, unburned air and unburned fuel in EGR output by the dedicated EGR cylinder during transient operation of the engine, and an effect of the EGR loop on inert matter, unburned air and unburned fuel provided to the plurality of cylinders, and controlling operation of at least one of the throttle, the ignition system and the plurality of injectors in response to at least one of the one or more combustion control parameters.

Methods and systems are provided for adjusting a substitution ratio based on water in a combustion mixture of a multi-fuel engine. In one example, a method includes adjusting a substitution ratio in response to an amount of water provided to a multi-fuel engine configured to combust a first fuel and a second fuel, the second fuel different than the first fuel.

An embodiment apparatus for reducing fouling of an exhaust gas recirculation (EGR) cooler includes an exhaust gas transfer part configured to connect a diesel oxidation catalyst (DOC) of an exhaust gas post-treatment system extending from an engine through an exhaust line to an EGR cooler installed in an EGR line and configured to recirculate exhaust gas discharged from an exhaust manifold to an intake manifold, a valve installed in the exhaust gas transfer part, and a controller configured to selectively open the valve as the exhaust gas post-treatment system enters a predetermined diesel particulate filter (DPF) regeneration condition and allow exhaust gas discharged from the DOC to be supplied to the EGR cooler through the exhaust gas transfer part.

An embodiment apparatus for reducing fouling of an exhaust gas recirculation (EGR) cooler includes an exhaust gas transfer part configured to connect a diesel oxidation catalyst (DOC) of an exhaust gas post-treatment system extending from an engine through an exhaust line to an EGR cooler installed in an EGR line and configured to recirculate exhaust gas discharged from an exhaust manifold to an intake manifold, a valve installed in the exhaust gas transfer part, and a controller configured to selectively open the valve as the exhaust gas post-treatment system enters a predetermined diesel particulate filter (DPF) regeneration condition and allow exhaust gas discharged from the DOC to be supplied to the EGR cooler through the exhaust gas transfer part.

The present disclosure relates to a gas engine heat pump including: an engine which burns a mixed air of air and fuel; a first charger which compresses the mixed air and supplies to the engine; a first exhaust flow path which is connected to the engine, and through which exhaust gas discharged from the engine flows; and a second charger which is driven by the exhaust gas branched from the first exhaust flow path to a second exhaust flow path, and compresses the exhaust gas discharged from the engine and supplies the compressed exhaust gas to the engine, thereby reducing the emission of nitrogen oxide by recirculating the exhaust gas without additional power consumption.

A system includes an internal combustion engine having a number of cylinders, with at least one of the cylinder(s) being a primary EGR cylinder that is dedicated to provided EGR flow during at least some operating conditions. A controller is structured to control combustion conditions in the cylinders in response to one or more operating conditions associated with the engine.

A method for operating an oxycombustion engine system includes passing a nitrogen-depleted gas, a fuel, and a recycled exhaust gas into a combustion chamber, combusting a mixture of the nitrogen-depleted gas, the fuel, and the recycled exhaust gas, thereby producing an exhaust gas including carbon dioxide, detecting a pressure of the recycled exhaust gas passed to the combustion chamber, determining whether the detected pressure of the recycled exhaust gas is less than a configurable pressure threshold, and in response to determining that the detected pressure of the recycled exhaust gas is less than the configurable pressure threshold, increasing the pressure of the recycled exhaust gas passed to the combustion chamber.

The present disclosure relates to exhaust treatment systems and engine systems. In one implementation, an engine system comprises an engine comprising an intake manifold and an exhaust manifold, the engine configured to combust a fuel-air mixture received via the intake manifold and produce a flow of exhaust gases via the exhaust manifold. The engine system also comprises a turbocharger comprising a turbine, an exhaust passageway fluidly connecting the exhaust manifold of the engine to the turbine and an intake passageway fluidly connected to the intake manifold of the engine for supplying the fuel-air mixture, a catalyzed member positioned along the exhaust passageway between the engine and the turbine, and an exhaust gas recirculation (EGR) loop fluidly connected downstream of the catalyzed member and fluidly connected to the exhaust passageway and the intake passageway.

The present disclosure relates to exhaust treatment systems and engine systems. In one implementation, an engine system comprises an engine comprising an intake manifold and an exhaust manifold, the engine configured to combust a fuel-air mixture received via the intake manifold and produce a flow of exhaust gases via the exhaust manifold. The engine system also comprises a turbocharger comprising a turbine, an exhaust passageway fluidly connecting the exhaust manifold of the engine to the turbine and an intake passageway fluidly connected to the intake manifold of the engine for supplying the fuel-air mixture, a catalyzed member positioned along the exhaust passageway between the engine and the turbine, and an exhaust gas recirculation (EGR) loop fluidly connected downstream of the catalyzed member and fluidly connected to the exhaust passageway and the intake passageway.