Abstract: Described here are systems and methods for reducing emissions of IC engines using a fuel processor bypass. In general, the systems described here include an exhaust pipe, a bypass pipe, a valve, a fuel processor, a fuel injector, and a NOx trap. When the valve is in the open position, the entire exhaust passes through the bypass pipe. When the valve is in a closed position, the entire exhaust passes through the exhaust pipe. In some variations, the systems described here also comprise a pre-combustor, a thermal mass, a mixer, and/or a DPF. Methods for regenerating or desulfating a NOx trap are also described. Typically these methods include introducing exhaust into an exhaust pipe, opening a valve located at the inlet of a bypass pipe, injecting fuel upstream of a fuel processor, and introducing a reducing mixture into a NOx trap. The injection of fuel may be pulsed or continuous.

Abstract: A system for controlling the temperature of an exhaust stream includes a main exhaust passageway adapted to receive the exhaust stream from an engine. A bypass passage includes an inlet and an outlet in communication with the main exhaust passageway. The outlet is located downstream from the inlet. A burner is positioned within the bypass passage for treating the exhaust passing through the bypass passage. A valve is positioned within the main exhaust passageway downstream from the inlet and upstream from the outlet. The valve is operable to vary the exhaust flow through the burner. A controller selectively operates the burner to maintain a desired exhaust temperature downstream of the outlet.

Abstract: The disclosure sets forth operating a spark-ignition, direct-fuel injection internal combustion engine equipped with an exhaust aftertreatment system including a lean-NOx reduction catalyst upstream of a second converter element. The engine preferentially operates in one of a homogeneous charge combustion mode and a stratified charge combustion mode based upon temperature of the lean-NOx reduction catalyst. Exhaust gas flow is selectively diverted to the second converter element.

Abstract: A system for removing particulates from the exhaust gas of a vehicle internal combustion engine, particularly during those times that the emission of such particulates into the atmosphere would be of greatest danger to persons in the vicinity of the vehicle, includes a valve connected to the vehicle exhaust manifold for normally directing exhaust to the atmosphere, when in the non-activated condition. The valve directs exhaust to a particulate filter, when in the activated condition. Starting of the engine activates the valve for a predetermined period of time. The valve optionally is GPS-controlled and can be disabled manually or automatically by a switch, which detects the backpressure in the exhaust system. An exhaust pressure sensor monitors the exhaust backpressure, and a circuit device responsive to the exhaust pressure maintains the valve continuously in the non-activated condition, when the exhaust backpressure reaches a predetermined level for a predetermined period of time.

Abstract: A method of directing flow of exhaust gas includes directing a first portion of the flow through a first flow path and directing a second portion of the flow through a second flow path. A temperature of at least a portion of the flow in the first flow path is increased, and the flow in the first flow path is sent through a filter. The first and second portions of the flow downstream of the filter to are combined form a combined flow. The combined flow is maintained within a predetermined range of temperatures, and the combined flow is directed to a catalyst.

Abstract: A system for treating exhaust gases from an engine is described. The system includes, the exhaust gases routed from the engine to atmosphere through an exhaust passage, the system comprising: an injector directing a spray of reductant into the exhaust gases routed from the engine to atmosphere; an exhaust separation passage that separates an exhaust gas flow received from the engine into a plurality of separate exhaust gas flows; a plurality of oxidation catalysts, each of which receives one of the plurality of separate exhaust gas flows; a flow combining passage that receives the plurality of separate exhaust gas flows and combines them into a re-combined exhaust gas flow; a turbocharger that receives the re-combined exhaust gas flow from the flow combining passage; and a selective catalytic reduction catalyst positioned downstream of the turbocharger.

Abstract: An exhaust gas purifying apparatus for an internal combustion engine is provided.

Abstract: The present invention provides a technology enabling regeneration of the purification performance of an exhaust purification device more reliably and more efficiently in an exhaust purification system combining a plurality of branch passages bifurcating from an exhaust passage and an exhaust purification device provided in each branch passage. When regenerating the purification performance of a first exhaust purification device provided in a first branch passage, a second valve provided in a second branch passage is set at a predetermined first intermediate opening and a first valve provided in the first branch passage is fully closed. Fuel is then added from a first fuel addition valve provided in the first branch passage.

Abstract: An exhaust-cleaning device for internal combustion engines having varying exhaust amount, which is intended to constitute a part of an exhaust system co-operating with an engine includes a main converter and a pre-converter located upstream the main converter, seen in the direction that exhaust fumes are intended to pass the exhaust-cleaning device. The exhaust-cleaning device is distinguished by a bypass arranged in the area of the pre-converter. The bypass includes a first opening upstream the pre-converter, and a second opening downstream the pre-converter and upstream the main converter, so that at least a part of the exhaust fumes passes past the pre-converter without passing therethrough. An extension for an exhaust-cleaning device and a vehicle including such an exhaust-cleaning device are disclosed.

Abstract: An engine having a first and second bank of cylinders is disclosed. The engine may have improved fuel economy and emission as compared to other similar engines. In one example, engine cylinders may be deactivated.

Abstract: Exhaust gas post treatment system for nitrogen oxide and particle reduction of an internal combustion engines operated with excess air. An oxidation catalytic converter is disposed in the exhaust gas stream of the engine for converting at least a portion of the nitric oxide of the exhaust gas into nitrogen dioxide. A metering device adds reduction agent to the exhaust gas stream downstream of the oxidation catalytic converter and/or to a partial exhaust gas stream branched off upstream of the oxidation catalytic converter and returned to the exhaust gas stream downstream thereof. The reduction agent is ammonia or a material that releases ammonia downstream of the supply location due to the hot exhaust gas.

Abstract: An exhaust gas purifying apparatus is provided for efficiently purifying particulate matter discharged from an internal combustion engine at a lower exhaust gas temperature by adequately disposing of the absorbent material for absorbing hydrocarbon, the combustion catalyst for hydrocarbon, and the combustion catalyst for particulate matter. The exhaust gas purifying apparatus disposed in an exhaust gas path of the internal combustion engine for purifying particulate matter in exhaust gas discharged from the internal combustion engine, includes a particulate filter, wherein the particulate filter has a porous wall; a first layer formed on a surface of the porous wall, including an absorbent material for absorbing hydrocarbon contained in exhaust gas; and a second layer formed on a surface of the first layer, containing a combustion catalyst for the particulate matter and a combustion catalyst for the hydrocarbon.

Abstract: The present invention discloses an exhaust system for an internal combustion engine that provides diesel particulate filter (DPF) failure detection and/or monitoring of nonmethane hydrocarbons (NMHC) for an internal combustion engine. The system can include a main exhaust duct and a secondary exhaust line operative for exhaust gas to pass therethrough. The system has an oxidation catalyst and a main particulate filter located in line with the main exhaust duct. A monitoring particulate filter is also included and located within the secondary exhaust line. The secondary exhaust line and the monitoring particulate filter are located downstream from the main particulate filter.

Abstract: A particle filter arrangement for filtering exhaust gases of an internal combustion engine such as a diesel internal combustion engine, includes an inlet and an outlet and at least one particle filter arranged in the flow path of the exhaust gases between the inlet and outlet. The exhaust gases are conducted in a line, with the line having a first segment in which the exhaust gases are conducted substantially in the direction of the outlet. The line has a second segment in which the exhaust gases are conducted substantially in the direction of the inlet. An operating temperature of the arrangement sufficiently high to prevent full loading of the filter is generated particularly quickly in that the line also includes a third segment in which the exhaust gases are conducted substantially in the direction of the outlet.

Abstract: An exhaust gas aftertreatment device includes a single intake path for an exhaust gas feedstream from an internal combustion engine and a coated substrate including a first substrate portion fluidly in parallel with a second substrate portion. A flow modification device selectively restricts flow of the exhaust gas feedstream exclusively to the first substrate portion, exclusively to the second substrate portion, and concurrently to the first substrate portion and the second substrate portion in controllably variable proportions.

Abstract: An exhaust treatment system associated with a power source is disclosed. The exhaust treatment system may have a filter located to remove particulate matter from a flow of exhaust, and a regeneration device located proximal the filter. The exhaust treatment system may also have a first fluid handling component located upstream of the power source to vary an amount of oxygen in the flow of exhaust, a second fluid handling component located downstream of the power source to vary the amount of exhaust air flow in the exhaust circuit, and a controller in communication with the regeneration device and the fluid handling component. The controller may determine a need for filter regeneration, and determine adjustments to the first and second fluid handling components required to provide sufficient oxygen and air mass flow in the exhaust for filter regeneration.

Abstract: An exhaust gas cleaning apparatus is provided that has a main exhaust passage, a main catalytic converter disposed in the main exhaust passage, a bypass exhaust passage, a bypass catalytic converter disposed in the bypass exhaust passage, a selector valve and a controller. The controller controls the internal combustion engine to a rich combustion state with a rich air fuel ratio while the controller controls the selector valve to block the flow of the exhaust gas through the main exhaust passage, and then, afterwards, controls the selector valve to direct the flow of the exhaust gas through the main exhaust passage such that residual air remaining in the main exhaust passage mixes with rich exhaust gas from the bypass exhaust passage.

Abstract: When a misfire occurs in any cylinder of an engine, an exhaust switching valve is closed to pass exhaust gas through an HC adsorbing section to a catalytic purifying section having a three-way catalyst (step S130). Thus, unburned fuel (HC) mixed in the exhaust gas due to a misfire of the engine can be adsorbed in the HC adsorbing section. Accordingly, unburned fuel (HC) due to a misfire after the start of the engine is completed can be prevented from being exhausted.

Abstract: In an exhaust purification system that purifies exhaust from a plurality of cylinder groups of an internal combustion engine, an exhaust passageway (1,51) from each cylinder group is divided into a plurality of passageways (2a, 2b, 52a, 52b/3,53). With regard to one or more of the divided exhaust passageways (3,53), the amount of exhaust passing therethrough is reduced so as to reduce the heat release to the outside from the exhaust as a whole. In this manner, the temperature of exhaust introduced into an exhaust purification device (4,54) is kept at high temperature.

Abstract: A moisture adsorbent (32) for adsorbing moisture in exhaust gas and an NOx adsorbent (34) for adsorbing NOx are disposed in a bypass passage (30) for bypassing an exhaust passage (16) of an internal combustion engine (10). When an adsorption operation to the NOx adsorbent (34) is executed, inflow of the exhaust gas to the bypass passage (30) is allowed until the moisture amount that flows into the water adsorbent (32) reaches an allowable moisture inflow amount. The allowable moisture inflow amount is determined based on a residual moisture amount before the starting of the adsorption operation in the moisture adsorbent (32). The residual moisture amount in the water adsorbent (32) can be determined based on the temperature of the moisture adsorbent (32) at the immediately preceding execution of the purge operation.

Abstract: An internal combustion engine includes a main catalyst disposed in a main passage and a bypass catalyst disposed in a bypass passage bypassing the main passage on an upstream side of the main catalyst. The bypass passage has a smaller transverse cross-sectional area than the main passage. The internal combustion engine further includes a passage open/close unit, a residual gas amount changing unit, and a controller. The passage open/close unit is disposed in a portion of the main passage bypassed by the bypass passage to switch between an open state and a closed state. The residual gas amount changing unit is configured to change an amount of residual gas inside a combustion chamber. The controller is configured to control the residual gas amount changing unit when a passage opening condition for switching the passage open/close unit from the closed state to the open state is satisfied.

Abstract: Art is provided for an exhaust purification system for an internal combustion engine, which decreases an amount of exhaust flowing to a storage-reduction type NOx catalyst and supplies a reducer to the NOx catalyst so as to reduce NOx stored in the NOx catalyst, wherein the manner in which the reducer is dispersed in the NOx catalyst can be controlled to achieve more reliable execution of a NOx reduction treatment. Air-fuel ratio detecting unit is disposed upstream and downstream of the storage-reduction type NOx catalyst. During a predetermined period subsequent to decreasing an amount of exhaust flowing to the NOx catalyst and adding the reducer to the exhaust, a reducer-adding timing is changed such that a difference between an air-fuel ratio detected by the air-fuel ratio detecting unit disposed upstream of the NOx catalyst and an air-fuel ratio detected by the air-fuel ratio detecting unit disposed downstream of the NOx catalyst becomes a predetermined target value.

Abstract: An apparatus, system, and method are disclosed for enhancing the efficiency of an exhaust aftertreatment application. The method may include determining the current operating conditions of the application, the optimal operating conditions of a target component, and the performance criteria of a conditioning component relative to the optimal operating conditions. The method may include determining an optimal fraction of an exhaust flow to pass through the conditioning component to achieve the optimal operating conditions of the target component. The method may further include manipulating a bypass valve position based on the optimal fraction of exhaust flow to pass through the conditioning component. The target component may be a selective catalyst reduction (SCR) component that operates optimally at a designed NO2/NOx mole ratio. The conditioning component may be a diesel oxidation catalyst (DOC) that affects the NO2/NOx mole ratio.

Abstract: Exhaust gas post treatment system for nitrogen oxide reduction of internal combustion engines operated with excess air. A partial exhaust gas stream is branched off upstream of an SCR catalytic converter for reducing nitrogen oxides. A metering device delivers to the partial exhaust gas stream reduction agent, which is ammonia or a material that releases ammonia downstream of the supply location as a result of the hot exhaust gas. The partial exhaust gas stream is returned to the exhaust gas stream downstream of the supply location and upstream of the SCR catalytic converter, which reduces the 1J nitrogen oxides in the exhaust gas stream with the aid of the ammonia or released ammonia, by selective catalytic reduction, to nitrogen and water vapor.

Abstract: A means capable of supplying exhaust gas sufficiently imitating exhaust gas from actual diesel engines is provided. A PM generating apparatus has a constitution in which combustion air supplied to the space between a chassis and an outer casing via an air inlet is introduced into the space between the outer casing and an inner casing via through-holes of the outer casing, and a fuel injected by an fuel-injection means into the space between the chassis and the outer casing is introduced into the space between the outer casing and the inner casing via the through-holes of the outer casing, wherein the fuel is combusted to generate PM.

Abstract: A main exhaust passage 42 and a first bypass passage 46 bypassing the main exhaust passage 42 are provided. An absorbent 52 having a function of absorbing HC components and NOx components contained in exhaust gas is provided in the first bypass passage 46. An underfloor catalyst 56 including a catalyst with an electric heater (EHC) 58 is provided in a main exhaust passage 42 on a downstream side of a downstream connecting portion 48b in a first bypass passage 46. A second bypass passage 62 that provides communication between the main exhaust passage 42 downstream of the underfloor catalyst 56 and the first bypass passage 46 upstream of the absorbent 52 is provided. A first exhaust switching valve 50 is provided in an upstream connecting portion 48a, and a second exhaust switching valve 68 is provided in a main exhaust passage side connecting portion 64a. A pump 66 is provided in the middle of the second bypass passage 62.

Abstract: An exhaust treatment system for use with a power system is disclosed. The exhaust treatment system may have an SCR device (32), and an oxidation device (26) located upstream of the SCR device (32) to convert NO to NO2. The exhaust treatment system may also have an exhaust passageway (14) extending from an exhaust source (10) to the oxidation device (26), and a bypass passageway (24) extending from the exhaust passageway at a location upstream of the oxidation device to the exhaust passageway at a location downstream of the oxidation device (26). The exhaust treatment system may further have a valve element (20) configured to selectively direct exhaust from the exhaust source (10) through the oxidation device (26) and through the bypass passageway (24), at least one sensor configured to sense operating parameters of the exhaust source (10), and a controller (36) in communication with the valve element (20).

Abstract: An apparatus including an exhaust passage that forks at a separating portion and joins at a joining portion, exhaust gas purification catalysts between the separating portion and the joining portion, a filter downstream of the joining portion, reducing agent supply units supplying reducing agent to the respective exhaust passages at positions upstream of the exhaust gas purification catalysts, and control units controlling quantity of the exhaust gas passing through the exhaust gas purification catalysts. When regenerating the filter, the reducing agent is supplied by one reducing agent supply unit, and the quantity of exhaust gas passing through the exhaust gas purification catalyst provided in the exhaust passage to which the reducing agent is supplied is made smaller.

Abstract: A reforming device includes a reforming part that subjects a hydrocarbon-based raw material to be reformed to a reforming reaction to form a reducing agent to be supplied to a reducing catalyst for reducing nitrogen oxide selectively. The reforming part has a reforming reaction region through which the raw material to be reformed passes and is reacted with supplied hydrogen atoms supplied so as to be reformed to the reducing agent. For example, a hydrogen permeable membrane having a first surface and a second surface may be provided in the reforming part to permeate hydrogen atoms from the first surface to the second surface and to produce the hydrogen atoms on the second surface. The reforming device can be suitably used for an exhaust gas control system for cleaning exhaust gas, for example.

Abstract: An exhaust gas passageway of an internal combustion engine is basically provided with a main exhaust passageway, a bypass exhaust passageway, a bypass catalytic converter provided in the bypass exhaust passageway, a bypass control valve, an upstream air-fuel ratio sensor and a downstream air-fuel ratio sensor. The bypass exhaust passageway bypasses a portion of the main exhaust passageway between an upstream junction and a downstream junction. The bypass control valve opens or closes a portion of the main exhaust passageway. The upstream air-fuel ratio sensor is disposed upstream of the bypass catalytic converter to sense air-fuel ratio of an exhaust gas flowing into the bypass catalytic converter. The downstream air-fuel ratio sensor is disposed downstream of the bypass catalytic converter to sense air-fuel ratio of the exhaust gas flowing out of the bypass catalytic converter.

Abstract: A system for providing heat to the dump body of a dump truck is disclosed. The disclosed system is suitable for use with truck equipped with a diesel particulate filter. When enabled, the system controls the exit path of exhaust gas such that it is routed to the dump body during normal operating conditions. In one embodiment, when the diesel particulate filter enters a regeneration cycle, high heat is produced. The system then routes the exhaust gas as to bypass the dump body to avoid heat damage from the higher temperature exhaust gas.

Abstract: A catalyst system that may regenerate while removing pollutants from an exhaust gas of an engine. The system may have a converter with multiple segments of chambers. At least one of the chambers may be regenerated while the remaining chambers are removing pollutants from the exhaust. The chambers may be rotated in turn for one-at-a-time regeneration. More than one chamber may be regenerated at a time to remove collected pollutants. The system may have plumbing and valves, and possibly mechanical movement of the chambers, within the system to effect the changing of a chamber for regeneration. The chambers connected to the exhaust may be in series or parallel. A particulate matter filter may be connected to the system, and it also may be regenerated to remove collected matter.

Abstract: A diesel engine exhaust treatment system has both a NOx reduction device and a diesel particulate filter. The system is designed to ensure that the NOx reduction device operates within its optimal temperature conditions. Using exhaust flow control valves, the exhaust flow can be directed into either the NOx reduction device first or into the diesel particulate filter first, and then into the other device, before exiting out the tailpipe.

Abstract: The invention relates to a system and a control method for an exhaust aftertreatment system (10) of an engine (12) in which one or more constituents of the exhaust gas are oxidized in an oxidation catalyst (20) and one or more constituents of the exhaust gas are deoxidized in a selective-catalytic-reduction catalyst (70), wherein the exhaust gas flows from the oxidation catalyst (20) to the selective-catalytic-reduction catalyst (70). It is.

Abstract: An object of the present invention is to provide an exhaust gas purifying apparatus for an internal combustion engine which can properly purge at least NOx of unpurified components contained in exhaust gas while considering characteristics of NOx desorbed from an adsorbent. A bypass passage 18 bypassing a main exhaust passage 12 of the internal combustion engine 10 is provided. A HC/NOx adsorbent 22 having a function of adsorbing HC and NOx is provided in the bypass passage 18. A second underfloor catalyst 30 is provided downstream of the adsorbent 22. A purge passage 26 branching off from the bypass passage 18 while connecting to an intake passage is provided. An exhaust switching valve 20 and a purge control valve 28 are provided as a flow path switching means that is capable of switching a flow target into which the exhaust gas flows between the main exhaust passage 12 and the bypass passage 18. If the purging operations are executed, the intake purging operation is first executed.

Abstract: A plurality of upstream main exhaust passages extend from cylinders of an engine. A downstream main exhaust passage is connected to the upstream main exhaust passages. A main catalytic converter is mounted in the downstream main exhaust passage. A plurality of upstream bypass exhaust passages extend from the upstream main exhaust passages. Each upstream bypass exhaust passage has a sectional area smaller than that of the corresponding upstream main exhaust passage. A downstream bypass exhaust passage is connected to the upstream bypass exhaust passages and has a downstream end connected to the downstream main exhaust passage at a position upstream of the main catalytic converter. An auxiliary catalytic converter is mounted in the downstream bypass exhaust passage. A gas flow switching device is provided which is capable of forcing the exhaust gas from the cylinders of the engine to flow toward the upstream bypass exhaust passages when assuming a given operation position.

Abstract: An exhaust system for a combustion source is disclosed. The exhaust system may have a passageway connected to receive an exhaust flow from the combustion source, and a sensor disposed within the passageway. The sensor may generate a signal indicative of the concentration of a constituent in the exhaust flow. The exhaust system may also have a controller in communication with the sensor to receive the signal. The controller may be configured to selectively communicate a flow of calibration gas with the sensor during operation of the combustion source, and compare the signal received during the selective communication with a reference value. The controller may be further configured to adjust the sensor output in response to the comparison.

Abstract: In an exhaust gas system for an internal combustion engine, particularly of a motor vehicle, wherein the exhaust gas system comprises a nitrogen oxide reducing converter arranged in an exhaust gas line of the internal combustion engine, an exhaust gas cleaning device arranged upstream of the nitrogen oxide reducing converter and a reducing agent feed device for feeding a reducing agent into the exhaust gas of the internal combustion engine upstream of the nitrogen oxide reducing converter, a bypass line is provided which branches off from the exhaust gas line upstream of the exhaust gas cleaning device and rejoins the exhaust gas line at an entry point downstream of the exhaust gas cleaning device and upstream of the nitrogen oxide reducing converter.

Abstract: A method and system for managing an exhaust gas feedstream from an internal combustion engine operative lean of stoichiometry includes steps and apparatus for diverting exhaust around a three-way catalytic converter during NOx adsorber regeneration thereby increasing reductants available in the NOx adsorber to react with the adsorbed NOx.

Abstract: In a treatment for regenerating the purification capability of an exhaust emission control system, a technique for improving exhaust emission more positively is provided by supplying a reducing agent to the exhaust emission control system and allowing part of exhaust to bypass the exhaust emission control system. When an addition synchronous bypass control is carried out in which an reducing agent is added when an NSR is subject to NOx reduction treatment and the volume of exhaust passing through a bypass pipe out of exhaust passing an exhaust pipe is increased to thereby decrease the volume of exhaust passing through the NSR, a judgment is made (S106) as to which is larger a reduction in volume of Nox exhausted (S105) due to an increase in conversion efficiency of the NSR as the result of the addition synchronous bypass control carried out or an increase in volume of Nox exhausted (S103) due to an increase in exhaust passing through the bypass pipe.

Abstract: An exhaust emission control system for an internal combustion engine is disclosed. The exhaust emission control system has a first passageway and a second passageway disposed to receive exhaust in parallel. The exhaust emission control system also has a valve arrangement configured to regulate the flow of exhaust to the first and second passageways, and at least one sensor configured to sense a parameter indicative of a constituent of the exhaust. The at least one sensor generates a signal corresponding to the sensed parameter. The exhaust emission control system also has a controller in communication with the valve and the at least one sensor. The controller is configured to affect operation of the valve in response to the signal.

Abstract: The present invention relates to an exhaust system for an internal combustion engine, in particular in a motor vehicle, with an exhaust line in which an oxidation catalyst is provided for treatment of the exhaust gases coming from the internal combustion engine. To be able to heat the oxidation catalyst more rapidly in a cold start of the internal combustion engine, a pre-oxidation unit may be provided in the exhaust line upstream from the oxidation catalyst and connected to a secondary fuel supply and adapted so that it partially oxidizes the secondary fuel supplied in combination with an oxidizer in a catalyst heating operation and the partially oxidized intermediate products are supplied to the oxidation catalyst for complete oxidation.

Abstract: In a method for operating an exhaust-gas cleaning unit of a diesel engine including a particle filter and a nitrogen oxide storage device arranged upstream of the particle filter, wherein sulfur regeneration of the nitrogen oxide storage device is performed periodically at raised exhaust gas temperatures and, in certain phases, with a rich exhaust gas composition, and also soot regeneration of the particle filter is performed at raised exhaust gas temperatures with a lean exhaust gas composition, at least some of the sulfur regeneration and the soot regeneration phases are performed in a combined soot and sulfur regeneration phase, and for the sulfur regeneration, at least temporarily, a rich exhaust-gas composition with a temperature higher than the temperature of the lean exhaust gas composition is provided for the soot regeneration of the particle filter.

Abstract: Method and systems are provided for operating an engine having a hydrocarbon retaining system coupled to an engine exhaust and an engine intake. One example method comprises, during an engine cold start, routing exhaust gas to the hydrocarbon retaining system to store hydrocarbons in the hydrocarbon retaining system. The method further comprises, during a first purging condition where the exhaust gas is at a first temperature, purging the hydrocarbon retaining system with at least exhaust gas, and during a second purging condition where the exhaust gas is at a second temperature, said second temperature being higher than said first temperature, mixing the exhaust gas with an amount of fresh air to form a purging gas mixture, and purging the hydrocarbon retaining system with said purging gas mixture.

Abstract: Various systems and methods are disclosed for carrying out combustion in a fuel-cut operation in some or all of the engine cylinders of a vehicle. Further, various subsystems are considered, such as fuel vapor purging, air-fuel ratio control, engine torque control, catalyst design, and exhaust system design.

Abstract: A reconfigurable exhaust system provides selective positioning of exhaust gas treatment devices either near, or spaced from, the exhaust gas outlet port of a turbine of a turbocharged Diesel engine. In some embodiments, auxiliary air or a heat exchanger are arranged to cool the exhaust gas when required.

Abstract: In an exhaust gas purification apparatus for an internal combustion engine (1) equipped with independent exhaust passages (2a, 2b) provided one for each cylinder group (1a, 1b) with a catalyst (3a, 3b) having a NOx trapping ability being arranged in each exhaust passage, the present invention is intended to provide a technique that can independently control the flow rates of exhaust gases flowing into the respective catalysts.

Abstract: A method for operating an internal combustion engine and a device for implementing the method, in which a diagnosis is performed of an adjusting device situated in the exhaust duct of the internal combustion engine, which distributes the exhaust gas between a first and at least one second exhaust gas path. A transit time from a change of a characteristic quantity of the exhaust gas in front of the adjusting device until the appearance behind the adjusting device detected by a sensor is compared to a specified transit time threshold value. The transit time threshold value is specified as a function of a setpoint position of the adjusting device. In the event of a deviation from or exceedance of the threshold value, a fault signal is provided.

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.

Abstract: An exhaust emission control system of an internal combustion engine desorbs SOx by reversing a flow of an exhaust gas through an NOx storage-reduction catalyst, of which a structure is simplified as follows. A first exhaust pipe connected to an engine is connected to a first port of an emission switching valve having four ports. A second exhaust pipe 10, through which the exhaust gas is discharged into the atmospheric air, is connected to a second port, a third exhaust pipe connected to an inlet of a catalytic converter is connected to a third port. A fourth exhaust pipe connected to an outlet of the catalytic converter 30 is connected to a fourth port. When the emission switching valve is set in a forward flow position, the first exhaust pipe is connected to the third exhaust pipe, and the second exhaust pipe is connected to the fourth exhaust pipe, whereby the exhaust gas flows toward the outlet from the inlet within the catalytic converter.