Abstract: The invention concerns a drive train, in particular for a motor vehicle, having a heat flow generating drive motor; having a steam engine in a steam circuit, in which a working fluid is evaporated and is expanded in the steam engine; having a evaporator, which is arranged in the steam circuit and is operated with at least one portion of the heat flow, so as to evaporate the working fluid; wherein the evaporator comprises an inlet for liquid working fluid and an outlet for evaporated working fluid. The invention is characterised in that that the evaporator moreover comprises an auxiliary outlet, via which a portion of the heated working fluid is guided through the inlet into the first evaporator and is discharged with the heat flow, before the residual working fluid in the evaporator is further evaporated by means of the heat flow.

Abstract: During a rich spike control for an exhaust gas purification system for an internal combustion engine, a base air-fuel ratio AFb is decreased in a range where a combustion variation ?CC does not exceed a permissible limit ?CCL (S108). When the combustion variation ?CC exceeds the permissible limit ?CCL, the spike base air-fuel ratio AFbs is increased (S213). When the torque decrease amount ?TD is above the permissible value ?TDL, the spike base air-fuel ratio AFbs is decreased (S215). When the combustion variation ?CC is above the permissible limit ?CCL, and the torque decrease amount ?TD is above the permissible value ?TDL, the spike base air-fuel ratio AFbs is increased, and a fuel discharge time number EN is increased (S216).

Abstract: An internal combustion engine control device includes a NOx adsorber catalyst disposed in an exhaust passage, an EGR passage, a reducing agent adding device, a torque fluctuation reducing device, and a fuel injection device. The EGR passage draws a portion of exhaust gas from the exhaust passage downstream of the NOx adsorber catalyst and recirculates the exhaust gas into the intake passage. The reducing agent adding device adds a reducing agent to exhaust gas upstream of the NOx adsorber catalyst to reduce substances adsorbed by the NOx adsorber catalyst. When or after the reducing agent adding device adds the reducing agent, the torque fluctuation reducing device advances the timing of the fuel injection device or carries out a pilot injection to reduce a fluctuation in engine torque. The reducing agent adding device adds less reducing agent while the torque fluctuation reducing device is operating.

Abstract: Improved exhaust gas recirculation system and methods that use one or more of the engine's cylinders as dedicated EGR cylinders. All of the exhaust from the dedicated EGR cylinders is recirculated back to the engine intake. Thus, the EGR rate is constant, but the EGR mass flow may be controlled by adjusting the air-fuel ratio of the dedicated EGR cylinders or by using various variable valve timing techniques.

Abstract: An apparatus for controlling engine operations to a low NOx output amount at low selective catalytic reduction (SCR) temperature values and alternatively for controlling engine operations in an EGR cooler bypass regime at low engine load levels is described. The apparatus includes a controller that interprets a present speed and a present load of an engine, that determines an engine operating region in response to the present speed and the present load, and that provides an EGR cooler bypass command that provides EGR cooler bypass flow in response to the engine operating region being a first, low load, region. The controller operates the engine with supplemental NOx management in response to the engine operating region being a second, intermediate load, region. The controller operates the engine without either of the EGR cooler bypass or the supplemental NOx management in response to the engine operating region being a third region.

Abstract: The invention relates to a diagnosis method for an exhaust gas post-treatment system for the reduction of nitric oxides in the exhaust gas train of an internal combustion engine by means of selective catalytic reduction.

Abstract: An exhaust gas purification system for an internal combustion engine, which is provided with: a selective reduction type catalyst arranged in an exhaust passage of the internal combustion engine; a low pressure EGR mechanism that is equipped with a low pressure EGR passage for introducing a part of an exhaust gas flowing through a portion of the exhaust passage downstream of a turbine of a centrifugal supercharger to a portion of an intake passage upstream of a compressor as a low pressure EGR gas, and a low pressure EGR valve for changing a channel cross section of the low pressure EGR passage; a supply device.

Abstract: Disclosed is a device and a method for neutralizing an acidic condensate in an internal combustion engine with exhaust gas recirculation system, wherein the exhaust gas recirculation system has an exhaust gas recirculation cooler for cooling a hot exhaust gas stream, a metering system is provided that meters an alkaline substance into the exhaust gas stream and is arranged upstream of the exhaust gas recirculation cooler.

Abstract: An EGR control method to prevent condensation within the EGR system uses a temperature sensor signal from an EGR cooler exhaust gas outlet to model or estimate exhaust manifold gas temperature upstream of the cooler. If the estimated exhaust manifold gas temperature falls below a predetermined level, the engine control system closes or partially closes the EGR control valve to stop EGR flow through the cooler and the EGR valve.

Abstract: An object of the present invention is to provide a technology of preventing, in an exhaust gas recirculation system having a low pressure EGR passage that recirculates a part of the exhaust gas from the exhaust passage at some point downstream of the exhaust gas purification apparatus to the intake passage, fragments of the exhaust gas purification apparatus from entering the intake system through the low pressure EGR passage in case that breakage of the exhaust gas purification apparatus occurs. The inventive system has a low pressure EGR valve provided in the low pressure EGR passage, an EGR control unit (S101-S103) for recirculating exhaust gas to the intake passage by opening the low pressure EGR valve, and a breakage detection unit (S104-S107) for detecting breakage of the exhaust gas purification apparatus. When breakage of the exhaust gas purification apparatus is detected, the low pressure EGR valve is closed (S108).

Abstract: A method for controlling an engine with exhaust gas recirculation is provided. The method comprises directing EGR from exhaust downstream of an exhaust-aftertreatment catalyst to mix with fresh air upstream of an intake compressor and upstream of a throttle valve, and, in response to increased throttling by the throttle valve, discharging the mixed EGR and fresh air from downstream of the intake compressor to the exhaust downstream of the exhaust-aftertreatment catalyst.

Abstract: A partition wall partitioning a cooler inlet port and a cooler outlet port extends from a cooler connecting surface of a connecting portion to a vicinity of a shaft supporting a four-way butterfly valve. An EGR gas leakage around a first valve plate can be restricted. Thus, an increase in temperature of EGR gas flowing through an EGR gas outlet port can be restricted at a cooled mode. A deterioration of emission reducing performance can be avoided.

Abstract: An exhaust gas purification device of an internal combustion engine having a NOx catalyst provided to an exhaust passage for occluding NOx in a lean atmosphere and for reducing the occluded NOx in a rich atmosphere has an exhaust gas recirculation passage for recirculating the exhaust gas from the exhaust passage to an intake passage, an exhaust gas recirculation valve provided in the exhaust gas recirculation passage, a rich combustion control section for performing rich combustion in the internal combustion engine, and an exhaust gas recirculation valve control section for controlling an opening degree of the exhaust gas recirculation valve to conform a pressure value in the intake passage to a predetermined pressure value while the rich combustion control section performs the rich combustion.

Abstract: An internal combustion engine exhaust system comprises an exhaust gas recirculation pipe which, in use, recirculates engine exhaust gas into the engine air intake. A particulate filter is provided and a burner arrangement is arranged to burn off particulates caught by the filter.

Abstract: A heat exchanging system suitable for use in an exhaust gas recirculation (EGR) circuit comprises a split EGR heat exchanger arrangement. Exhaust gas is used to warm engine oil via a first heat exchanger during initial stages of an engine operating cycle. In the later stages of the operating cycle, recirculated exhaust gases are diverted to flow through the second heat exchanger where they are cooled by the engine coolant.

Abstract: An internal combustion engine, in which intake air flows through an intake passage into a combustion chamber and exhaust gas resulting from the combustion in the combustion chamber flows through an exhaust passage, includes an exhaust gas purifier provided in the exhaust passage and having an oxidation catalyst, an LPL-EGR passage connecting between the intake passage and the exhaust passage at a position downstream of the exhaust gas purifier as seen in exhaust gas flow direction, a first estimating device for estimating exhaust gas composition at a position upstream of the exhaust gas purifier, a second estimating device for estimating exhaust gas composition at a position downstream of the exhaust gas purifier, a cylinder temperature adjusting device for adjusting temperature in the combustion chamber, and a controller for controlling the cylinder temperature adjusting device based on the difference in the exhaust gas composition between the first and second estimating devices.

Abstract: Methods and systems are provided for managing exhaust gases from an internal combustion engine are described. In one example system, hydrocarbons in engine exhaust gases may be stored during an engine cold start and later released into an intake manifold of the engine. The methods and systems may reduce engine hydrocarbon emissions.

Abstract: A control method for an internal combustion engine including an exhaust gases post-processing system and a system for recirculating the exhaust gases towards the intake, wherein the engine can be switched from a regeneration operation mode with throttling to a nominal mode without throttling. At the end of the engine operation in the regeneration mode, the engine is temporarily operated in an intermediate mode with partial throttling for limiting the contrast of the intake noise.

Abstract: Systems, methods, and computer readable storage media are described in which exhaust gas is routed to a hydrocarbon retaining device during starting, and purged to the engine intake manifold. Various alternative approaches are described for controlling operation and diagnosing degradation. Further, various interrelated configurations are described.

Abstract: In an attempt to regenerate energy of exhaust gas by using a pressure regenerator secured to an exhaust port of a displacement type engine so as to realize the Atkinson's cycle, if the engine is a four-cycle engine, raising regenerative pressure may cause abnormal fuel combustion or melting damage of an exhaust valve. The present invention has successfully solved this problem by using a six-cycle engine. The six-cycle engine with a regenerator according to the present invention is capable of varying proportion of the power output that is generated by the six-cycle engine itself and that is generated by the regenerator. Using this principle enables the six-cycle engine with a generator to be used as an engine that is capable of generating two kinds of output power or as a six-cycle gas turbine with high controllability.

Abstract: An exhaust recovery system for use with an internal combustion engine having an air intake device connected to an air/fuel mixing device. The system comprises an improved muffler having a vortex inducing filter mechanism inside the muffler chamber that facilitates separation of engine exhaust air into cool and hot gas streams and encloses a filter element that filters out particulate matter and other pollutants. Engine exhaust air is circumferentially discharged into the muffler chamber and a cone member is disposed inside the chamber to separate and direct the gas streams. The cooled gas stream is redirected to the air intake device through an outlet pipe at the first end of the muffler so pressurized cooled air is directed into the air/fuel mixing device to improve engine performance and efficiency. The filtered hot gas stream is discharged to the environment out a discharge pipe at the second end of the muffler.

Abstract: Various systems and method are described for controlling an engine having an exhaust system which includes a particulate filter. One example method comprises, after shutting down the engine and spinning down the engine to rest, operating a vacuum pump to draw fresh air through the exhaust system to an intake system, and regenerating at least a portion of the particulate filter during the engine rest.

Abstract: A gas separation process for treating exhaust gases from the combustion of gaseous fuels, and gaseous fuel combustion processes including such gas separation. The invention involves routing a first portion of the exhaust stream to a carbon dioxide capture step, while simultaneously flowing a second portion of the exhaust gas stream across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas back to the combustor.

Abstract: An internal-combustion engine receives no air from outside atmosphere and it discharges no gas into outside atmosphere. The engine receives fuel, oxygen and recycled combustion gas and its exhaust consists mostly of carbon dioxide and water vapor. Most of the gas exhausted from the engine is recycled back into the engine intake, and the remaining gas is cooled and condensed into liquid carbon dioxide and water. Discharge of greenhouse gas into environment and emission of other harmful air pollutants are eliminated.

Abstract: An exhaust system for use with an engine is disclosed. The exhaust system may have an exhaust passageway, a reduction catalyst located within the exhaust passageway, and a particulate filter located within the exhaust passageway upstream of the reduction catalyst. The exhaust system may also have an oxidation catalyst located within the exhaust passageway upstream of the reduction catalyst to provide a desired ratio of NO:NO2 to the reduction catalyst, and an exhaust gas recirculation loop. The exhaust gas recirculation loop may be situated to receive exhaust from the exhaust passageway at a location upstream of the oxidation catalyst and downstream of the particulate filter.

Abstract: An exhaust gas recirculation system (10) for recirculating exhaust gases from an exhaust conduit (9) of a combustion engine (1), particularly a large combustion engine having an engine power of 500 kW or more, to an air intake (3) thereof, which system comprises:—two or more particulate filters (12a, 12b) arranged in parallel with each other;—valve means (17) for selectively switching the respective filter between an active state and an inactive state, the valve means being configured to allow exhaust gases to pass from the exhaust conduit to the air intake through a filter which is in the active state and to prevent exhaust gases from passing from the exhaust conduit to the air intake through a filter which is in the inactive state; and—filter regeneration means (40) for selectively initiating a regeneration of the respective filter when the filter is in the inactive state.

Abstract: A method of operating an internal combustion engine having an intake, an exhaust, and a turbocharger including a turbine and a compressor, the compressor coupled to the intake and the turbine coupled to the exhaust, the engine further having an exhaust gas recirculation system coupled to the exhaust upstream of the turbine and coupled to the intake downstream of the compressor, the method including transferring heat via a heat exchanger from the exhaust gas recirculation system to downstream of the turbine.

Abstract: An ECU executes the program including the step acquiring a catalyst temperature when the execution condition for fuel-cut control is satisfied the step selecting a throttle opening degree based on the catalyst temperature; the step executing fuel-cut control; and the step executing return control from fuel-cut control when the condition for returning from fuel-cut control is satisfied.

Abstract: An exhaust gas cleaning apparatus is provided with an exhaust gas particulate filter, an oxidation catalytic converter and a regeneration control component. The exhaust gas particulate filter is arranged in an exhaust passage of an internal combustion engine for capturing particulate matter in exhaust gas from the internal combustion engine. The oxidation catalytic converter is arranged upstream of the exhaust gas particulate filter in the exhaust passage. The regeneration control component is configured to control an exhaust gas recirculation rate and a temperature of recirculated exhaust gas being recirculated to an air induction system of the internal combustion engine for controlling a temperature of the exhaust gas particulate filter and a concentration of nitrogen dioxide in the exhaust gas particulate filter such that nitrogen dioxide generated by the oxidation catalytic converter is used to burn the particulate matter captured in the exhaust gas particulate filter.

Abstract: An exhaust aftertreatment system for treating an exhaust gas feedstream of an internal combustion engine includes a catalytic converter, a fluidic circuit and a Stirling engine. The Stirling engine is configured to transform thermal energy from a working fluid heat exchanger to mechanical power that is transferable to an electric motor/generator to generate electric power. The Stirling engine is configured to transform mechanical power from the electric motor/generator to thermal energy transferable to the working fluid heat exchanger.

Abstract: A system and method are disclosed for providing exhaust-gas recirculation in an internal combustion engine that has an exhaust-gas turbocharger. The exhaust gas to be recirculated is collected from the exhaust line downstream of a turbine of the turbocharger, passed through a condensate separator, and supplied into the intake line upstream of the compressor. The condensate is filtered, collected in a reservoir, and pumped to an injection device coupled to the engine intake at a location downstream of the compressor.

Abstract: Methods and systems are provided for operating a turbocharged engine including a particulate filter positioned upstream of a turbocharger turbine, a catalyst positioned downstream of the turbine, and an EGR passage coupled between an engine exhaust and engine intake. In one example, the method comprises, diverting exhaust gas from downstream of the filter to the engine intake via the EGR passage, and adjusting an amount of diverted exhaust gas based on filter operating conditions.

Abstract: An exhaust gas cleaning apparatus includes a LNT, a fuel adding device, an exhaust gas returning passage, and a controller. The LNT is provided in an exhaust gas passage of an engine. The fuel adding device is located upstream of the LNT to add fuel to exhaust gas flowing through the exhaust pipe. The exhaust gas returning passage branches off from the exhaust gas passage at a position downstream of the fuel adding device. The controller controls the apparatus to selectively operate in one of first and second modes according to the operating condition of the engine. In the first mode, the fuel adding device adds the fuel to the exhaust gas with the exhaust gas returning passage closed; in the second mode, the exhaust gas is partially returned to an intake air passage through the exhaust gas returning passage without the fuel being added by the fuel adding device.

Abstract: An exhaust purification apparatus for an engine comprises a selective reduction-type NOx catalyst that is interposed in an exhaust passage of the engine and selectively reduces NOx contained in exhaust gas of the engine, an EGR device that recirculates exhaust gas of the engine to an intake side of the engine, an exhaust-purification-efficiency estimation unit that estimates exhaust purification efficiency of the NOx catalyst with respect to NOx, a target-exhaust-purification-efficiency calculation unit that calculates target exhaust purification efficiency with respect to NOx on the basis of an operational state of the engine, and a control unit that controls the EGR device to compensate a decrease amount of the estimated exhaust purification efficiency to the target exhaust purification efficiency.

Abstract: A two-stroke uniflow scavenged diesel engine system including an exhaust gas recirculation (EGR) system is described for reducing NOX emissions and achieving desired fuel economy by recirculating exhaust gas through the engine. More specifically, the present invention is directed to a pressure balance exhaust gas recirculation (EGR) assembly for a two-stroke locomotive diesel engine having an EGR system. The present pressure balance EGR assembly includes an EGR module adapted to define a space between the external housing wall of the DOC housing and the inner wall of the EGR module housing and a space between the external wall of the DPF housing and the inner wall of the EGR module housing. One side of each space is confined by a flange-gasket arrangement, whereas the other side of the space is in open communication with the outlet of the respective DOC or DPF such that a portion of the exhaust fills each space.

Abstract: A configuration for treating exhaust gases of an internal combustion engine having a predetermined displacement volume, includes an exhaust gas recirculation line. Exhaust gas flowing through the exhaust gas recirculation line interacts with a turbocharger. A screening layer is provided in the exhaust gas recirculation line upstream of the turbocharger. The screening layer is larger than an average cross section of the exhaust gas recirculation line. A motor vehicle having at least one such configuration is also provided.

Abstract: A method for improving operation of a turbocharged engine is presented. In one embodiment, the method may reduce engine emissions and improve engine efficiency during an engine start.

Abstract: A method is provided for maintaining the heat in an exhaust after treatment system connected to the exhaust pipe of an internal combustion engine. The engine is used to propel a vehicle and is equipped with a valve-controlled EGR duct for the adjustable recirculation of exhaust gases from the exhaust side of the engine to its induction side. According to the invention, it is detected that neither the braking system nor the throttle control mechanism of the vehicle is activated and that the vehicle is being driven at a speed in excess of a predetermined value. After this, the gas flow through the EGR duct is regulated so that the gas flow to the exhaust aftertreatment system is reduced to a level which is less than about 50% of the gas flow to the exhaust aftertreatment system with shut-off EGR valve.

Abstract: An object of the present invention is that after return from fuel cut, an oxygen storage amount in a catalyst in an exhaust path and an oxygen storage amount in a catalyst in an exhaust gas recirculating path are promptly adjusted to be in appropriate states, respectively. A control apparatus for an internal combustion engine of the present invention controls the internal combustion engine including a recirculating gas generating cylinder and a recirculating gas nongenerating cylinder. The control apparatus includes: an exhaust gas recirculating path for connecting the exhaust path through which exhaust gas only in the recirculating gas generating cylinder is delivered and an intake system; a recirculating catalyst provided on the exhaust gas recirculating path; and rich control means that performs rich control for controlling an air-fuel ratio to be temporarily richer than a theoretical air-fuel ratio when fuel injection is restarted after return from the fuel cut.

Abstract: A compression ignition internal combustion engine system combusts DME as fuel using high fuel injection pressures (e.g., above 800 bar) and low oxygen concentrations (e.g., below 17%, through high levels of EGR), thereby resulting in simultaneously very low NOx and PM engine-out emissions.

Abstract: A working gas circulation engine includes a combustion chamber that can expand a working gas, which has a specific heat ratio higher than that of the air, with the combustion between an oxidizing agent and a fuel; a circulation path that can allow the working gas to circulate from a suction side to an exhaust side of the combustion chamber and can supply the same again to the combustion chamber; a feed means that can feed the gas in a pressure-reduction target section, which is the section whose pressure is to be reduced, to the outside, and a control means that operates the feed means for feeding the gas in the pressure-reduction target section, when the pressure in the pressure-reduction target section is higher than a predetermined pressure that is set in advance.

Abstract: Method and device for reduction of a gas component in an exhaust gas flow of a combustion engine (1) that is adapted for operation by a lean air/fuel mixture. An exhaust pipe (21) is included for transport of the exhaust gas flow from the engine (1). A separation unit (22) is also included that is arranged along the exhaust pipe (21), which separation unit (22) has a wall structure (32) of a material which provides separation of the gas component from the exhaust gas flow by means of a selective passage of the gas component before other gas components in the exhaust gas flow. The method provides for a reduction and a separation unit that is intended to be utilized during such a reduction. An improved reduction of in particular NOx compounds from a so-called “lean-burn” engine is also provided.

Abstract: A portion of the exhaust generated by a turbomachine is recirculated through an inlet portion by an exhaust gas recirculation system. The system reduces the level of Sulfur Oxides and other constituents within the exhaust before the exhaust is recirculated. The system may utilize sea water, fresh water, or combinations thereof; as part of a scrubbing process to reduce the Sulfur Oxides and other constituents.

Abstract: A control apparatus for an internal combustion engine includes an exhaust gas recirculation unit; an intercooler that is provided in the intake passage, at a position downstream of a position to which the exhaust gas is recirculated back; a bypass passage through which an intake air flow bypasses the intercooler. When it is determined that the pH of the condensed water obtained from the exhaust gas is at the level at which the intercooler corrodes in the state where the exhaust gas is recirculated back by the exhaust gas recirculation unit, the control apparatus executes a control for cutting off an intake air flow toward the intercooler to direct the intake air flow only to the bypass passage. Thus, it is possible to ensure reliability of the intercooler.

Abstract: An exhaust heat exchanger includes a water tank accommodating tubes and having an outside space defined outside of the tubes, a gas tank having an exhaust passage and an outside space defined outside of the exhaust passage, a dividing portion to separate the outside space of the water tank from the exhaust passage of the gas tank, and a communication portion. The outside space of the gas tank and the outside space of the water tank communicate with each other through the communication portion.

Abstract: Disclosed herein are combustion systems and power plants that incorporate sweep-based membrane separation units to remove carbon dioxide from combustion gases. In its most basic embodiment, the invention is a combustion system that includes three discrete units: a combustion unit, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In a preferred embodiment, the invention is a power plant including a combustion unit, a power generation system, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In both of these embodiments, the carbon dioxide capture unit and the sweep-based membrane separation unit are configured to be operated in parallel, by which we mean that each unit is adapted to receive exhaust gases from the combustion unit without such gases first passing through the other unit.

Abstract: A power assembly includes an internal combustion engine including an air intake line and an exhaust gas line having at least one heat exchanger. The power assembly further includes a Brayton cycle system capable of providing additional power to the main internal combustion engine and that includes a gas compressor, a fuel burning heater and a turbine linked to the compressor so that air is drawn into the compressor where it is pressurized, the pressurized air is further heated by flowing through at least one heat exchanger where it exchanges heat with exhaust gases from the main internal combustion engine, the heated and pressurized air is further heated by the fuel burning heater and is thereafter expanded through the turbine where a first fraction of the work extracted by the turbine is used to drive the compressor and a second fraction of the work extracted by the turbine is used to bring additional energy.

Abstract: A pressure accumulation system for an internal combustion engine can prevent exhaust pressure from excessively increasing when pressurized gas is contained in a pressure accumulation container. A pressure accumulation system is applied for an internal combustion engine provided with an exhaust shut-off valve mounted in an exhaust path. The pressure accumulation system has a pressure accumulation tank into which gas can be introduced from that portion of an exhaust path. The pressure accumulation system also has a sensor for detecting the exhaust pressure, and an EGR valve is controlled based on the detection value from the exhaust gas sensor such that the pressure in that portion of the exhaust path which is on the upstream of the exhaust shut-off valve is limited below a predetermined exhaust gas upper limit value (Pmax) when gas is contained in the pressure accumulation tank.

Abstract: A gas separation process for treating flue gases from combustion processes, and combustion processes including such gas separation. The invention involves routing a first portion of the flue gas stream to be treated to a carbon dioxide capture step, while simultaneously flowing a second portion of the flue gas across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas to the combustor.

Abstract: A system for purifying exhaust gas generated by an internal combustion engine including a bypass branching out from the exhaust pipe downstream of a catalyst and merging to the exhaust pipe, an adsorber installed in the bypass, a bypass valve member which closes the bypass, and an EGR conduit connected to the bypass at one end and connected to the air intake system for recirculating the exhaust gas to the air intake system. The bypass valve member is opened for a period after engine startup to introduce the exhaust gas such that the adsorber installed in the bypass adsorbs the unburnt HC component in the exhaust gas. The adsorber adsorbs the HC component when the exhaust temperature rises and the adsorbed component is recirculated to the air intake system through the EGR conduit. In the system, the bypass valve is provided at or close to the branching point in the exhaust pipe and a chamber is provided close to the branching point such that the conduit is connected to the bypass at the one end in the chamber.