Abstract: A particulate filter 8 is disposed in an exhaust passage 7 of an internal combustion engine 1, and a reduction catalyst 9 is disposed downstream of the particulate filter 8. A bypass passage 12 for bypassing the reduction catalyst 9 and a flow path switching valve 13 which switches a flow path for the exhaust gas which has passed through the particulate filter 8 between the exhaust passage 7 and the bypass passage 12 are disposed. A control unit 301 controls the flow path switching valve 13 in association with a temperature Texh of the exhaust gas which has passed through the particulate filter 8.

Abstract: An engine system includes first and second combustion chamber groups that supply exhaust to respective first and second exhaust passages. NOx in the exhaust of the first combustion group is converted to ammonia, such as by enriching the exhaust with fuel and then passing the mixture over an appropriate catalyst. Particles are trapped and continuously oxidized through appropriate placement of one or more particle traps coated with an appropriate oxidizing catalyst. NOx in the second passage from the second combustion group is combined with ammonia produced in the first passage and converted to nitrogen and water in a merged passage before being vented to atmosphere. This conversion is accomplished by passing the merged exhaust over an appropriate selective catalytic reduction catalyst.

Abstract: A bypass passage is provided, which connects a portion upstream of a turbine of a supercharger in an exhaust passage to a portion close to a front end surface of exhaust gas purification in the exhaust passage, and through which at least part of exhaust gas discharged from an internal combustion engine flows. The exhaust gas discharged from the bypass passage is blown to the front end surface of the exhaust gas purification means in a lateral direction of the front end surface, whereby particulate matter deposited in the front end surface of the exhaust gas purification means is blown off.

Abstract: An exhaust system for an internal-combustion engine comprises an exhaust bypass in parallel with an upstream portion of a main exhaust path having a main catalytic converter in a downstream portion thereof; an exhaust bypass catalytic converter provided in the exhaust bypass; and a flow path switching valve for blocking the main exhaust path at the upstream portion thereof. The exhaust system includes an ignition timing adjustment mechanism for adjusting ignition timing to delay sparking when the flow path switching valve is switched from the closed condition to the open condition thereof. A control method for the exhaust system is also disclosed.

Abstract: An exhaust-gas purification system and method are provided for an internal combustion engine having an NOx storage catalytic converter and a downstream SCR catalytic converter. The NOx storage catalytic converter can be supplied in a first operating mode with an oxidizing exhaust gas and in a second operating mode with a reducing exhaust gas. A third operating mode is provided between the first operating mode and the second operating mode, in which an exhaust gas which has a lower content of oxidizing constituents than the first operating mode and a lower content of reducing constituents than the second operating mode can be supplied to the NOx storage catalytic converter to improve NH3 production at the start of converter regeneration.

Abstract: An exhaust emission control device includes an adsorbent trapper having an adsorbent for adsorbing and desorbing hydrocarbon in exhaust gas, a catalytic converter, a main exhaust gas passage with a first valve, a bypass exhaust gas passage with a second valve and a control unit. The bypass exhaust gas passage bypassing the first valve is connected with the adsorbent. The control unit controls the first and second valves to desorb the hydrocarbon from the adsorbent when a condition is satisfied. The condition is that the catalyst converter is in active, an oxygen adsorption amount of the catalyst converter is not less than a first predetermined amount and an exhaust gas amount is not more than a second predetermined amount. The first valve is opened and the second valve is closed when the condition is not satisfied during desorption of the hydrocarbon from the adsorbent.

Abstract: An exhaust system of the internal combustion engine comprises upstream main paths for cylinders that are attached to a side of a cylinder head and extend towards a side of the engine, and are connected to the respective cylinders; a downstream main path in which the upstream main paths join so as to become one flow path; a main catalytic converter provided on the downstream main path; bypasses that are split from the upstream main paths or the downstream main path; a bypass catalytic converter that is provided on the bypass; and flow path switching valves that open and close the upstream main paths so that exhaust discharged from the cylinders flows into the bypass. The bypass catalytic converter is provided below the upstream main paths.

Abstract: A system comprising an engine having a first and second bank of cylinders, said first bank having a first and second group of cylinders, said second bank having a third and fourth group of cylinders; a first emission control device coupled to said first and second group for treating gasses from said first and second group separately; a second emission control device coupled to said third and fourth group for treating gasses from said third and fourth group separately; and a controller for operating said first and third group about stoichiometry and said second and fourth group to pump air without injected fuel.

Abstract: An exhaust system for treating an exhaust gas composition having NO2 in a first NO2 concentration. The exhaust system includes a first catalyst that contacts a first portion of the exhaust gas composition converting it into a first oxidized exhaust mixture that includes NO2 in a second NO2 concentration that is greater than the first NO2 concentration. The system further includes a bypass that receives a second portion of the exhaust gas composition and a recombination section positioned downstream of the first catalyst. The first oxidized exhaust mixture is combined with the second portion of the exhaust gas composition to produce a first combined exhaust gas mixture. A second catalyst converts the first combined exhaust gas mixture to a second combined exhaust gas mixture having a third NO2 concentration that is less than the second NO2 concentration. The method used by the exhaust system is also provided.

Abstract: A hydraulic assembly and method for use with an vehicle engine exhaust flow control valve for controlling flow to at least one intake supply. The assembly has an actuator, such as a spring return piston cylinder, for positioning the control valve. An inlet passage, communicating with the cylinder, is arranged for supplying hydraulic fluid to a side of the actuator and a drain is arranged for draining the hydraulic fluid from the side of the actuator. An on-off type hydraulic valve, communicating with the drain, is operably coupled to the cylinder for controlling communication of the hydraulic fluid from the cylinder side to the drain. When the hydraulic assembly is in use, the pressure of hydraulic fluid acting on the actuator is adjustable by operation of the on-off type valve thereby to control movement of the actuator and, in turn, movement of the control valve.

Abstract: To provide an engine exhaust gas treatment system that can efficiently reduce and remove NOx using easy-to-handle urea as the reducing agent, regardless of the engine operating conditions. An exhaust gas denitration system in which an exhaust gas is introduced into the denitration catalyst reactor 5 provided in the exhaust gas flue 3, where NOx is reduced and removed in the presence of the denitrati on catalyst, wherein a diversion means provided in the exhaust gas flue 3 introduces part or all of the exhaust gas into a urea solution injection evaporator having a heating means by the heater 30, and the heat from the exhaust gas and the heat from the heater serve to generate ammonia that is then circled and mixed with the exhaust gas and introduced into the denitration catalyst reactor 4.

Abstract: An exhaust system of an internal combustion engine having at least one cylinder comprises a main exhaust passage connected to the cylinder; a main catalytic converter disposed in the main exhaust passage; a bypass exhaust passage that diverges from the main exhaust passage, the bypass exhaust passage having a gas flow resistance larger than that of the main exhaust passage and having a downstream end connected to the main exhaust passage at a position upstream of the main catalytic converter; an auxiliary catalytic converter disposed in the bypass exhaust passage; and a gas flow switching device that is capable of forcing exhaust gas from the cylinder of the engine to flow toward the bypass exhaust passage when assuming a given operation position.

Abstract: An apparatus, system, and method are disclosed for particulate filter regeneration. The apparatus includes a bypass exhaust channel configured to conduct exhaust gasses away from a main exhaust channel and reintroduce the exhaust gasses into the main exhaust channel upstream from a particulate filter, a burner, and a regeneration module configured to monitor exhaust gas variables and divert a portion of the exhaust gasses through the bypass exhaust channel in response to the exhaust gas variables. The system includes a vehicle having an internal combustion engine coupled to a transmission, and the apparatus. The method includes conducting exhaust gasses away from a main exhaust channel and reintroducing the exhaust gasses into the main exhaust channel, raising the temperature of the exhaust gasses, and monitoring exhaust gas variables and selectively diverting a portion of the exhaust gasses through a bypass exhaust channel in response to the exhaust gas variables.

Abstract: The invention concerns a structure (11) comprising a filtering member (21) comprising intake conduits (35) for the gases to be filtered, and conduits (37) for extracting the filtered gases, separated from the intake conduits (35) by porous filtering walls (43). The intake conduits (35) emerge into openings (49) for discharging respective residues, provided downstream of the respective intake openings (47). The openings discharging residues (49) of the intake conduits (35) open into a common manifold (25) for receiving solid filtering residues, forming counter-pressure means for the intake conduits (35). Said manifold (25) is isolated from the extracting conduits (37). The invention is applicable to particulate filters for exhaust gases of a motor vehicle diesel engine.

Abstract: The invention relates to an exhaust gas line for exhaust gas from at least one cylinder of an internal combustion engine, having at least one collecting housing (1) with a connection to an exhaust gas recirculation system (2). The collecting housing (1) is designed as a section of the exhaust gas line for the internal combustion engine.

Abstract: An exhaust treatment system is provided having a first exhaust passageway fluidly connected to an engine. A particulate filter and a selective catalytic reduction catalyst are situated within the first exhaust passageway. In addition, the system has a first oxidation catalyst located within the first exhaust passageway upstream of the particulate filter and the selective catalytic reduction catalyst. The system also has a second exhaust passageway fluidly connected to the first exhaust passageway upstream and downstream of the first oxidation catalyst. The exhaust treatment system further has a sensor configured to sense a parameter indicative of an exhaust gas temperature. Furthermore, the system has a controller configured to direct exhaust gas through the first oxidation catalyst when the exhaust gas temperature is below a threshold temperature and direct the exhaust gas through the second exhaust passageway when the exhaust gas temperature is above the threshold temperature.

Abstract: The aftertreatment apparatus and method of the invention concentrate diesel exhaust under low engine load conditions in a motor vehicle, such as idling, before filtering the diesel exhaust. The apparatus has a housing which is in fluid communication with a filter and other components of the diesel exhaust system. The apparatus has an exhaust concentrator to concentrate the low load diesel exhaust. The concentrated exhaust is directed a limited part of the filter and/or the catalytic device, such as the center. The exhaust concentrator is at least partially disposed within the housing.

Abstract: The invention relates to an exhaust line (10) for a heat engine, comprising a nitrogen oxide trap (28) which is installed on a filter section (24) between an exhaust inlet (12) and an exhaust outlet (14). The invention also comprises: a bypass section (26) which is disposed between the nitrogen oxide trap (28) and the exhaust inlet (12) in order to divert the exhaust gas away from the nitrogen oxide trap (28), and exhaust gas switching means (32, 24) which enable the gases to flow through the filter section (24) or the bypass section (26).

Abstract: An exhaust gas control apparatus for an engine and a method for producing the same are provided. The exhaust gas control apparatus includes a valve portion, an absorption portion, and a catalyst portion. The valve portion includes a valve that opens/closes a main exhaust passage. The absorption portion includes a hydrocarbon-absorbent that absorbs hydrocarbons. The catalyst portion includes a three-way catalyst that purifies exhaust gas. The valve portion, absorption portion, and the catalyst portion are independent of each other. The valve portion, the absorption portion, and the catalyst portion are connected to each other in series. With this configuration, any individual component can be replaced with another corresponding component that achieves a required level of performance while minimizing the number of other components.

Abstract: A cost-effective solution to remove particulates from diesel, especially light-duty diesel engines incorporates an oxidation catalyst (2) effective to convert NO in the exhaust from the engine to NO2 and a particulate trap (4) which traps no more than 85% by weight of the particulate, optionally by permitting gas to by-pass the trap.

Abstract: Attained is a heat generative exhaust emission control device with less electric power consumption and with no harmful gas discharged to atmosphere. A porous filter body 7 for capturing particulates in exhaust gas 2 through passing of the exhaust gas 2 is provided with an electric heater 9 so as to heat the filter body 7; thus, a heat regenerative particulate filter 10 is provided. The heat regenerative particulate filters 10 are accommodated in filter casings 11 and 12 within an exhaust pipe 3, and oxidation catalysts 13 and 14 are arranged upstream and downstream of and adjacent to the heat regenerative particulate filter 10 so as to obtain thermo-keeping or heat insulation effect to the heat regenerative particulate filter 10.

Abstract: An internal combustion engine with exhaust gas aftertreatment and method for the operation thereof are provided. The internal combustion engine includes at least one first and one second group of one or more combustion chambers, in which the one or more combustion chambers of the first group may be supplied with fuel independently of the one or more combustion chambers of the second group, an exhaust system having a first exhaust branch line which leads away from the first combustion chamber group, and a second exhaust branch line which leads away from the second combustion chamber group, and at least one exhaust gas aftertreatment unit which, at the inlet side, is connected to the first and second exhaust branch lines. Also, a bypass line, which leads away from the second exhaust branch line, for bypassing the exhaust gas aftertreatment unit is provided.

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: The present invention prevents an EGR sensor installed in an engine's EGR path from being soiled by soiling substances in exhaust. A catalyst is positioned upstream of the EGR sensor to purify the soiling substances in EGR gas. The status of the EGR sensor is properly controlled in accordance with the conditions of the catalyst. This ensures the EGR sensor is less likely to be affected by the soiling substances in the exhaust under any circumstances of the EGR path and allows the EGR sensor to avoid a decrease in the accuracy of EGR gas detection. An alternative configuration may be employed such that the EGR gas recirculates from the downstream side of a catalyst installed in a main exhaust path.

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, having an exhaust line for removing exhaust gas from the internal combustion engine and having a secondary fuel supply for introducing secondary fuel into the exhaust gas of the internal combustion engine. To improve the introduction of the secondary fuel into the exhaust, a recirculation device is connected to the exhaust line and to the secondary fuel supply so that the introduction of secondary fuel into the exhaust is accomplished via or through the recirculation device. The recirculation device has a circulation space which receives an exhaust substream from the exhaust line in which the secondary fuel is introduced into the exhaust substream and from which the modified exhaust substream is returned to the exhaust line.

Abstract: One embodiment of a method of operating a NOx abatement system comprises: introducing an exhaust stream to an ammonia generator in a normal flow direction, adsorbing NOx from the exhaust stream in the ammonia generator, diverting the exhaust stream around the ammonia generator, introducing hydrogen to the ammonia generator in a direction opposite the normal flow direction, and generating ammonia within the ammonia generator.

Abstract: A compact reversing flow catalytic converter with protection from overheating includes a valve unit which directs exhaust gases through a container filled with catalytic material to permit a bypass of catalytic material when a temperature of the material exceeds a predetermined threshold. The container defines a U-shaped gas passage that communicates with two ports at the top of the container. The valve unit is mounted to the top of the container and includes an intake and an exhaust cavity. The valve unit includes a valve disk having two openings therethrough. The valve disk rotates around perpendicular central axis between a first, a second and third positions. When overheating of the catalytic material is predicted, a controller relinquishes control of the valve disk and a center return mechanism rotates the valve disk to a third position, in which each of the openings communicates with both ports so that the exhaust gas flow bypasses catalytic material.

Abstract: A dual NOx trap system for reducing NOx emissions from an internal combustion engine. The system is plumbed and controlled such that the NOx adsorption time of a trap is decoupled from the NOx regeneration time. A trap is taken out of service for regeneration only for the minimum required regeneration time and then is placed back into service. Because regeneration times are short relative to adsorption times, during most of the working life of the assembly both of the traps are in service in NOx-trapping mode. Thus, higher NOx-trapping efficiencies are provided over most of the working life of the system because each unit volume of catalyst is in service for more than 50% of the time, permitting a smaller volume of catalyst for each trap than in a prior art system. Further, shorter off-line regeneration times result in reduced cooling of the traps during regeneration.

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: The present invention provides a honeycomb structure 1 comprising partition walls 2 so as to form a plurality of cells 3 extending from one end face 42 to the other end face 44, and a plug portion 4 plugging the cell 3 at the end face 42 and/or 44. In the honeycomb structure 1, the plug portion 4 has a hollow and convex shape, and at least a part of the plug portion 4 is protruding from the end face.

Abstract: An exhaust gas purifying equipment for a diesel engine having a first continuous regeneration type DPF (12) in an exhaust passage (7) of an engine (2), a second continuous regeneration type DPF (13) in a bypass passage (101), a switching valve (102) for switching the flow path of an exhaust gas, an exhaust temperature raising means, an exhaust temperature area detector, and a controller controlling the exhaust temperature raising means and the switching valve (102), wherein the controller operates the exhaust temperature raising means and at the same time executes the post-injection, and, furthermore, controls the switching valve (102) so that the exhaust gas passes through the second continuous regeneration type DPF (13), in the case where the exhaust temperature area of an engine (2) detected by the exhaust temperature area detector is in an extremely low temperature area (Z2) of which the exhaust temperature is lower than that of a predetermined temperature area.

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: Method and device for a particle filter for an exhaust system for a combustion engine, wherein the filter is regenerated by spontaneous combustion of particles accumulated in the filter. Exhaust gases from the combustion engine are led, during operation, past the filter when the counterpressure in the exhaust gases which is caused by the filter exceeds a certain level. The invention also relates to a silencer in a vehicle which is driven by the combustion engine.

Abstract: The present invention relates to a gas treatment apparatus for treating the exhaust gas stream from an internal combustion engine. The apparatus comprises several compartments within which one or more treatments are to be performed upon a gas flowing through the compartments. At least one compartment includes a treatment element secured against axial movement at each end. The treatment element is secured at least at one end by removable axial retaining apparatus. The removable axial retaining apparatus includes a secured member secured against axial movement. The treatment element is removable from within the compartment by axial movement after the removable axial retaining apparatus has been removed.

Abstract: A method for removal of dissolved oxygen from organic liquids by use of a solid state catalyst. In doing so the dissolved oxygen is converted by the action of a reducing agent into water.

Abstract: An apparatus for the reduction of nitric oxides (NOx) and particulate matter of exhaust emissions from a diesel engine having an electronic control module. The apparatus includes a first treatment device for reducing particulate matter and a second treatment device for reducing NOx emissions from the engine exhaust. The apparatus also includes a first valve in fluid communication with the exhaust inlet from the engine and a second valve in fluid communication with a common exhaust outlet. The first and second valves are in fluid communication with each other through a fluid connection extending therebetween.

Abstract: An exhaust aftertreatment system comprising two or more branches, at least one of which contains a NOx adsorber-catalyst. The branches unite downstream into a trailing conduit that contains an ammonia-SCR catalyst. Ammonia generated by the NOx adsorber-catalyst during regeneration is stored for later use by the SCR catalyst. One advantage of this configuration is a continuous or near continuous presence of oxygen within the trailing exhaust conduit. The continuous presence of improves the efficiency of the SCR catalyst. Another concept is to configure a multi-branch exhaust aftertreatment system without valves, dampers, or other electronically controlled devices adapted to selectively alter the distribution of the exhaust between the branches. The absence of such devices generally results in a comparatively balanced division of exhaust between the branches. One benefit of this configuration is improved reliability as compared to systems that use valves.

Abstract: An exhaust manifold includes an open/close valve that switches between either closing or opening the exhaust path of a collection section, and switches the exhaust path of the exhaust gas between passing through or not passing through a bypass path containing an upstream catalyst. There is a partition wall structure in a pipe-mounting member so that when the valve is closed such that the exhaust gas during cold start is led to the upstream catalyst, the exhaust paths for each of the branch pipes on the upstream side of the valve inside a collection section are independent from one another. When the valve is closed, the downstream side of each of the branch pipes is not continuous inside the collection section, so the flow of air is prevented in this section, and exhaust interference and loss of exhaust heat are reduced.

Abstract: An exhaust gas purification apparatus for an engine includes an exhaust gas bypass connected to the engine, a muffler connected to the exhaust gas bypass, and a catalytic carrier. The muffler defines an outlet communicating with the atmosphere. The catalytic carrier defines a through-hole for receiving catalyst. The catalytic carrier is mounted in the muffler, and at the outlet of the muffler. The through-hole of the catalytic carrier communicates with the atmosphere via the outlet.

Abstract: A secondary air pipe is connected to an exhaust pipe upstream of a catalyst, and a secondary air pump is connected to an upstream portion of the secondary air pipe. An ECU determines an operating period of the secondary air pump before the secondary air pump is operated in order to drive the secondary air pump within the operating period. Especially, the ECU detects a pump driving load during a secondary air supply to correct the operating period of the secondary air pump based on the detected pump driving load.

Abstract: An exhaust gas purification system has a first accumulation quantity estimation device that estimates an accumulation quantity of exhaust particulate matters collected by a diesel particulate filter (DPF) based on a flowing state of exhaust gas and a second accumulation quantity estimation device that estimates the accumulation quantity based on an operating state of an engine. The first estimation device is employed only when a flow rate of the exhaust gas is equal to or greater than a predetermined value and the engine is in a steady operating state. Otherwise, the second estimation device is employed. The exhaust gas flow rate is increased if the estimation by the second estimation device continues for a long time. Thus, an opportunity to perform the accumulation quantity estimation with the first estimation device is increased, and accumulation accuracy is improved.

Abstract: An internal combustion engine exhaust gas recirculation system. A turbine section of a turbocharger is coupled to an exhaust manifold of the engine. A compressor section has an output coupled to an intake manifold of the engine. The exhaust gas aftertreatment system is coupled to an output of the turbine section. The exhaust gas aftertreatment system includes a particulate filter having: a housing of an outer wall and an inner wall; a particulate filtering section disposed within the inner wall of the housing; and a channel formed between the inner wall and the outer wall. The channel created by the outer wall includes: an inlet disposed downstream of the filtering section for receiving a portion of exhaust gasses exiting the filtering section, and an outlet coupled to the input of the compressor section of the turbine for transporting the exhaust gasses received by the inlet of the channel to an input of the compressor section.

Abstract: A device for purifying the exhaust gas of an internal combustion engine is disclosed. The device includes a particulate filter arranged in the exhaust system, which carries a catalyst for absorbing and reducing NOx. The catalyst absorbs NOx when the air-fuel ratio in the surrounding atmosphere thereof is lean and releases the absorbed NOx to purify NOx by reduction when the air-fuel ratio is stoichiometric or rich. The device further includes a catalytic apparatus for purifying NOx arranged in the exhaust system upstream of the particulate filter, which has an oxidation function.

Abstract: An emissions control system utilizes otherwise wasted heat to efficiently reduce emissions in a main exhaust flow. Heat stored in exhaust from an auxiliary generator (i.e., auxiliary exhaust) may be used to convert urea to ammonia used by a Selective Catalytic Reducer (SCR) system, and/or the auxiliary exhaust may be used to heat the main exhaust flow before entry into an SCR. Additionally, a heat exchanger may be used to transfer heat from a hot clean flow out of the SCR, to the main exhaust flow entering the SCR. Previously, mobile emissions control systems have not used SCR systems to reduce NOx because of the cost and space required for heater fuel. The efficient use of otherwise wasted heat reduces fuel cost and fuel storage requirements, and thereby makes an SCR systems feasible for use in mobile emissions control systems.

Abstract: An exhaust gas aftertreatment device for an internal combustion engine comprises an inlet configured to receive the exhaust gas, an outlet from which the exhaust gas exits the device, a first passageway defined between the inlet and the outlet, and a second passageway defined between the inlet and the outlet, wherein the second passageway is separate from the first passageway. A first aftertreatment element is disposed in the first passageway. In one embodiment, the device is a diesel oxidation catalyst device and the second passageway represents a bypass passageway. The second passageway may further have a second aftertreatment element disposed therein. In an alternative embodiment, the device is a NOx aftertreatment element, and a second aftertreatment element is disposed in the second passageway. In either case, the device includes an exhaust gas flow control mechanism configured to selectively control exhaust gas flow through the first and second passageways.

Abstract: A system for measuring NOx content of an exhaust gas produced includes at least one controllable valve operable to direct exhaust gas to a NOx sensor only when measurement of the NOx content is desired and to otherwise expose the NOx sensor to ambient air. A control circuit controls the operation of the at least one valve and determines the NOx content of the exhaust gas based on sensory data received from the NOx sensor.

Abstract: Disclosed is an intelligent, full-featured diesel engine exhaust treatment system, including: an exhaust flowing zone, a microcomputer processor, and an exhaust detecting device, the exhaust flowing zone defining a first exhaust treatment path and a second exhaust treatment path, the microcomputer processor selectively employing a soot filter and a catalyst converter to purify the engine exhaust based on the state of contaminants in the engine exhaust as detected by the exhaust detecting device.

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 aftertreatment system comprising a NOx adsorber-catalyst followed by an SCR catalyst, means are provided for preventing the SCR catalyst from becoming heated to near the same peak temperatures as the NOx adsorber-catalyst during desulfation. In one embodiment, the means is a thermal mass between the NOx adsorber-catalyst and the SCR catalyst. In another embodiment, the means is a valve configured to selectively divert exhaust leaving the NOx adsorber-catalyst from the SCR catalyst. In a method of the invention, the NOx adsorber-catalyst temperature is cycled during desulfation. The peaks of the cycles are within an appropriate temperature range for desulfating the NOx adsorber-catalyst, but the average temperature is below the temperature range at which the SCR catalyst is damaged. The temperature peaks are damped as they travel from the NOx adsorber-catalyst to the SCR, whereby the SCR experiences much lower peak temperatures than the NOx adsorber-catalyst.