WO2012025976A1 - 内燃機関の排気浄化装置 - Google Patents
内燃機関の排気浄化装置 Download PDFInfo
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- WO2012025976A1 WO2012025976A1 PCT/JP2010/064182 JP2010064182W WO2012025976A1 WO 2012025976 A1 WO2012025976 A1 WO 2012025976A1 JP 2010064182 W JP2010064182 W JP 2010064182W WO 2012025976 A1 WO2012025976 A1 WO 2012025976A1
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- internal combustion
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
- F01N3/0828—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents characterised by the absorbed or adsorbed substances
- F01N3/0842—Nitrogen oxides
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
- F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N11/00—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
- F01N13/009—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
- F01N13/009—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series
- F01N13/0097—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series the purifying devices are arranged in a single housing
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
- F01N3/0871—Regulation of absorbents or adsorbents, e.g. purging
- F01N3/0885—Regeneration of deteriorated absorbents or adsorbents, e.g. desulfurization of NOx traps
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/101—Three-way catalysts
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/008—Controlling each cylinder individually
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/021—Introducing corrections for particular conditions exterior to the engine
- F02D41/0235—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus
- F02D41/027—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to purge or regenerate the exhaust gas treating apparatus
- F02D41/0275—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to purge or regenerate the exhaust gas treating apparatus the exhaust gas treating apparatus being a NOx trap or adsorbent
- F02D41/028—Desulfurisation of NOx traps or adsorbent
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2430/00—Influencing exhaust purification, e.g. starting of catalytic reaction, filter regeneration, or the like, by controlling engine operating characteristics
- F01N2430/06—Influencing exhaust purification, e.g. starting of catalytic reaction, filter regeneration, or the like, by controlling engine operating characteristics by varying fuel-air ratio, e.g. by enriching fuel-air mixture
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2550/00—Monitoring or diagnosing the deterioration of exhaust systems
- F01N2550/02—Catalytic activity of catalytic converters
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
- F01N3/0814—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents combined with catalytic converters, e.g. NOx absorption/storage reduction catalysts
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
- F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
- F01N3/2066—Selective catalytic reduction [SCR]
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/021—Introducing corrections for particular conditions exterior to the engine
- F02D41/0235—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus
- F02D41/024—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to increase temperature of the exhaust gas treating apparatus
- F02D41/025—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to increase temperature of the exhaust gas treating apparatus by changing the composition of the exhaust gas, e.g. for exothermic reaction on exhaust gas treating apparatus
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/40—Engine management systems
Definitions
- the present invention relates to an exhaust gas purification apparatus for an internal combustion engine, and more particularly to an exhaust gas purification apparatus for an internal combustion engine that includes a NOx storage reduction catalyst and a NOx selective reduction catalyst.
- a three-way catalyst, a NOx storage reduction catalyst (hereinafter referred to as “NSR catalyst”), and a NOx selective reduction catalyst (hereinafter referred to as “NOx catalyst”) are provided in the exhaust passage of an internal combustion engine.
- SCR NOx selective reduction catalyst
- NH 3 ammonia
- the SCR has a function of adsorbing ammonia (NH 3 ) and occludes NH 3 generated by the three-way catalyst and the NSR catalyst.
- the stored NH 3 is used when NOx flowing into the SCR is selectively reduced.
- the NSR catalyst is disposed in a region where the catalyst bed temperature is about 350 to 450 ° C. as a temperature environment suitable for NOx occlusion and purification reaction.
- this temperature range of the catalyst bed temperature is also suitable for the adhesion of sulfur components contained in the exhaust gas, the NSR catalyst causes deterioration due to sulfur poisoning in a relatively short time.
- the bed temperature of the NSR catalyst can be raised to 700 ° C. and exposed to a rich atmosphere to effectively desorb the adhering sulfur component. it can.
- enormous heat energy is required to raise the bed temperature of the NSR catalyst to 700 ° C.
- the present invention has been made to solve the above-described problems.
- an internal combustion engine including an NSR catalyst and an SCR
- the NSR catalyst is effectively prevented from sulfur poisoning while suppressing deterioration of fuel consumption and emission.
- An object of the present invention is to provide an exhaust emission control device for an internal combustion engine that can be recovered to a high level.
- a first invention is an exhaust purification device for an internal combustion engine capable of lean burn operation, A first catalyst disposed in an exhaust passage of the internal combustion engine and having a noble metal supported therein; A second catalyst disposed downstream of the first catalyst and having a noble metal and a base supported therein; A NOx selective reduction catalyst disposed in an exhaust passage on the downstream side of the second catalyst, The second catalyst is arranged in a predetermined exhaust upstream region in the exhaust passage.
- the second catalyst is arranged in a region where the bed temperature during operation is 500 to 750 ° C.
- the first catalyst and the second catalyst have a tandem structure integrated in a series arrangement.
- a fourth invention is any one of the first to third inventions, Determination means for determining whether sulfur poisoning of the second catalyst has progressed; A rich gas introduction means for introducing a rich gas into the second catalyst when it is determined that the sulfur poisoning has progressed; It is characterized by providing.
- a fifth invention is the fourth invention, Further comprising NOx concentration acquisition means for acquiring the NOx concentration of the exhaust gas downstream of the NOx selective reduction catalyst, The determination means determines that sulfur poisoning of the second catalyst has progressed when the NOx concentration is higher than a predetermined concentration.
- a sixth invention is the fourth or fifth invention, wherein The determination means determines that the sulfur poisoning of the second catalyst has progressed when the travel distance from the previous execution of the rich gas introduction means is longer than a predetermined distance.
- a seventh invention is the fourth to sixth inventions,
- the internal combustion engine is an internal combustion engine having a plurality of cylinders,
- the rich gas introducing means controls the exhaust air-fuel ratio of the first cylinder group to a predetermined rich air-fuel ratio among the first and second cylinder groups in which the plurality of cylinders are divided into two groups. It includes air-fuel ratio control means for controlling the exhaust air-fuel ratio of the cylinder group to a predetermined lean or stoichiometric air-fuel ratio.
- the rich gas introducing means introduces a rich rich exhaust gas into the second catalyst.
- Second determination means for determining whether it is time to perform abnormality diagnosis of the first catalyst; When it is time to perform an abnormality diagnosis of the first catalyst, active air-fuel ratio control is performed to forcibly and alternately switch the air-fuel ratio of the internal combustion engine between the rich side and the lean side with the theoretical air-fuel ratio as the control center. And an abnormality diagnosis means for executing an abnormality diagnosis of the first catalyst based on the oxygen storage capacity measured thereby,
- the rich gas introducing means includes When the abnormality diagnosis of the first catalyst is performed and it is determined that sulfur poisoning of the second catalyst is progressing, the control center in the active air-fuel ratio control is set in a rich direction by a predetermined amount. It is characterized by shifting to.
- the second catalyst is disposed in a predetermined exhaust upstream region.
- Such an exhaust upstream region is a region where the catalyst bed temperature becomes high due to heat transfer from the internal combustion engine and heat received from the high-temperature exhaust gas, so that the sulfur component hardly adheres to the basic substance. For this reason, according to this invention, the situation where sulfur poisoning of a 2nd catalyst advances in a short time can be suppressed effectively.
- the second catalyst is disposed in a region where the bed temperature during operation is 500 to 750 ° C. In such an operating temperature range, it is difficult for the sulfur component to adhere to the basic substance. For this reason, according to this invention, the situation where sulfur poisoning of a 2nd catalyst advances in a short time can be suppressed effectively.
- the first catalyst and the second catalyst are configured as a catalyst having an integral tandem structure arranged in series. For this reason, according to this invention, the cost reduction effect by reduction of a number of parts and simplification of a structure can be show
- the second catalyst In order to desorb the sulfur component from the second catalyst, it is necessary to raise the catalyst bed temperature to about 700 ° C. and expose the inside of the catalyst to a rich atmosphere.
- rich gas is introduced into the second catalyst. This rich gas component contributes to the temperature rise and rich atmosphere formation in the second catalyst. For this reason, according to the present invention, the second catalyst can be easily placed in a high temperature and rich atmosphere, so that the NSR catalyst can be easily recovered from sulfur poisoning.
- the fifth invention when the NOx concentration of the exhaust gas downstream of the NOx selective reduction catalyst (SCR) is higher than a predetermined concentration, it is determined that sulfur poisoning of the second catalyst has progressed.
- NOx is blown down on the downstream side of the SCR, NH 3 is insufficient in the SCR, that is, the sulfur poisoning of the second catalyst proceeds and the NH 3 production efficiency in the second catalyst is increased. It can be judged that has decreased. Therefore, according to the present invention, the progress degree of sulfur poisoning of the second catalyst can be effectively determined based on the NOx concentration on the downstream side of the SCR.
- the sulfur poisoning of the second catalyst has progressed when the travel distance from the previous execution of the sulfur poisoning regeneration process is longer than a predetermined distance.
- the sulfur poisoning of the second catalyst gradually proceeds as the continuous travel distance becomes longer. For this reason, according to this invention, based on this travel distance, the progress degree of the sulfur poisoning of a 2nd catalyst can be determined effectively.
- the exhaust air-fuel ratio of the first cylinder group is controlled to a predetermined rich air-fuel ratio
- the exhaust air-fuel ratio of the second cylinder group is controlled to a predetermined lean air-fuel ratio.
- the exhaust air / fuel ratio of the exhaust gas flowing into the catalyst can be effectively controlled to the rich air / fuel ratio.
- the slite rich gas is introduced into the second catalyst. For this reason, according to the present invention, it is possible to easily recover the NSR catalyst from sulfur poisoning while suppressing deterioration of emission and fuel consumption.
- the sulfur poisoning recovery process of the second catalyst can be executed in the process of executing the abnormality diagnosis of the first catalyst.
- Embodiment 1 of this invention It is a figure for demonstrating the structure of Embodiment 1 of this invention. It is a figure for demonstrating the internal structure of a TWC and an NSR catalyst. It is a flowchart of the routine performed in Embodiment 1 of the present invention. It is a flowchart of the routine performed in Embodiment 2 of this invention.
- FIG. 1 is a diagram for explaining the configuration of the first embodiment of the present invention.
- the system of the present embodiment includes an internal combustion engine (engine) 10.
- the internal combustion engine 10 is configured as a multi-cylinder engine (four cylinders in the figure), and each cylinder is provided with a fuel injection valve 12 for injecting fuel into the cylinder.
- the in-line four-cylinder engine is described in the system of FIG. 1, it may be configured as a V-type multi-cylinder engine.
- a direct injection type fuel injection valve that directly injects fuel into the cylinder is used as the fuel injection valve 12, but a port injection type fuel injection that injects fuel into the port of each cylinder.
- a valve may be used.
- An exhaust passage 16 communicates with the exhaust side of the internal combustion engine 10 via an exhaust manifold 14.
- a start catalyst (hereinafter referred to as “SC”) 20 is disposed in the exhaust passage 16.
- the SC 20 is intended to quickly purify the exhaust gas by exhibiting catalytic activity at the time of cold start of the internal combustion engine 10 and the like.
- the SC 20 is disposed in the exhaust upstream region, so that the bed temperature during operation is raised to 600 to 700 ° C.
- the SC 20 of the system according to the first embodiment is configured as a catalyst having a tandem structure including a three-way catalyst (hereinafter referred to as “TWC”) 201 in the front stage and an NSR catalyst (NOx storage reduction catalyst) 202 in the rear stage.
- TWC201 in SC20 is a lean atmosphere for oxygen (O 2) of NOx with adsorbed (purified to N 2) reducing.
- O 2 oxygen
- HC and CO are oxidized (purified to H 2 O, CO 2 ) while releasing oxygen.
- ammonia (NH 3 ) is generated by reacting nitrogen contained in the exhaust gas with hydrogen.
- the NSR catalyst 202 in SC20 occludes NOx contained in the exhaust gas under a lean atmosphere. Further, the NSR catalyst 202 releases NOx stored in a rich atmosphere. NOx released in a rich atmosphere is reduced by HC and CO. At this time, NH 3 is also generated in the NSR catalyst 202 as in the case of SC201.
- FIG. 2 is a view for explaining the internal structures of the TWC 201 and the NSR catalyst 202.
- (A) shows the internal structure of the TWC 201 in the front stage part
- (B) shows the internal structure of the NSR catalyst 202 in the rear stage part in detail.
- the TWC 201 supports Pt (or Pd) on the lower catalyst layer formed on the surface of the support base material, and Rh on the upper catalyst layer formed on the surface of the lower catalyst layer.
- a supported structure is preferable.
- Rh and Pt are separated and supported, it is possible to suppress Rh from solid-dissolving in Pd, thereby effectively suppressing the decrease in Pt oxidation activity and the reduction in Rh reduction activity. be able to.
- the NSR catalyst 202 supports Ph in the lower catalyst layer formed on the surface of the support substrate, and Pt (on the upper catalyst layer formed on the surface of the lower catalyst layer).
- Pt on the upper catalyst layer formed on the surface of the lower catalyst layer.
- a structure in which a NOx occlusion material composed of Pd) and a base is supported is preferable.
- Rh on the lower catalyst layer, H 2 generated by Rh in a rich atmosphere passes through the upper catalyst layer, so that the reduction and purification performance of the stored NOx can be effectively enhanced.
- an SCR (NOx selective reduction catalyst) 22 is disposed downstream of the SC 20 in the exhaust passage 16.
- the SCR 22 occludes NH 3 produced by the TWC 201 and the NSR catalyst 202 under a stoichiometric or rich atmosphere, and has a function of selectively reducing NOx in the exhaust gas using the NH 3 as a reducing agent under a lean atmosphere. Yes. According to the SCR 22, it is possible to effectively prevent a situation in which NH 3 and NOx blown down downstream of the SC 20 are released into the atmosphere.
- the system shown in FIG. 1 includes an air-fuel ratio (A / F) sensor 24 on the upstream side of the SC 20 in the exhaust passage 16.
- the A / F sensor 24 can detect the exhaust air / fuel ratio of the internal combustion engine 10.
- the system shown in FIG. 1 includes a NOx sensor 26 on the exhaust passage 16 downstream of the SCR 18.
- the NOx sensor 26 reacts with NOx and NH 3 in the exhaust gas and generates a signal corresponding to their concentration. For this reason, the NOx sensor 26 can detect the NH 3 concentration downstream of the SCR 22 under a rich atmosphere and the NOx concentration downstream of the SCR 22 under a lean atmosphere.
- the system according to the present embodiment includes an ECU (Electronic Control Unit) 30 as shown in FIG.
- ECU Electronic Control Unit
- Various actuators such as the fuel injection valve 12 described above are connected to the output portion of the ECU 30.
- various sensors for detecting the operating condition or operating state of the internal combustion engine 10 are connected to the input unit of the ECU 30.
- the ECU 30 can control the state of the system shown in FIG. 1 based on various types of input information.
- Embodiment 1 (NOx purification function of NSR catalyst 202)
- the ECU 30 normally operates the internal combustion engine 10 at a lean air-fuel ratio (lean operation).
- lean operation oxidizers such as NOx are discharged in a larger amount than reducing agents such as HC and CO. For this reason, even if it is going to purify the said exhaust gas using TWC201, all NOx cannot be purified by lack of a reducing agent. Therefore, the system according to the first embodiment includes an NSR catalyst 202 on the downstream side of the TWC 201.
- the NSR catalyst 202 has a function of storing NOx as nitrates such as Ba (NO 3 ) 2 . For this reason, according to the system of the first embodiment, it is possible to effectively suppress the situation where the NOx is released into the atmosphere even during the lean operation.
- the exhaust gas during execution of rich spike contains a large amount of reducing agent such as HC, CO, H 2 and the like.
- NOx stored as nitrate is reduced to NO and desorbed from the base.
- the desorbed NOx is purified to N 2 or the like on the catalyst in the NSR catalyst 202 and processed.
- the NOx occluded in the NSR catalyst 202 can be desorbed, so that the NOx occlusion performance can be effectively recovered.
- the catalyst bed temperature it is preferable to raise the catalyst bed temperature to about 350 to 450 ° C. in order to actively perform NOx occlusion / purification reaction in the NSR catalyst.
- the position of the NSR catalyst 202 is adjusted so that the bed temperature is raised to 500 to 750 ° C. The reason for this will be described later.
- NOx purification function of SCR22 Next, the NOx purification function of the SCR 22 will be described.
- the NOx storage performance of the NSR catalyst 202 can be effectively recovered by executing the rich spike.
- part of the NOx desorbed from the NSR catalyst 202 is blown downstream.
- the system according to the first embodiment includes an SCR 22 for processing NOx blown through the downstream side of the NSR catalyst 202.
- the SCR 22 occludes NH 3 produced by the TWC 201 and the NSR catalyst 202 in a rich atmosphere.
- NOx blown downstream of the NSR catalyst 202 can be selectively reduced and purified by NH 3 . Thereby, the situation where NOx is released into the atmosphere and the emission deteriorates can be effectively prevented.
- the reduction reaction in the SCR 22 can be actively performed by setting the bed temperature of the SCR 22 to 470 ° C. or less, preferably 200 to 350 ° C.
- the arrangement of the SCR 22 is adjusted so that the floor temperature of the SCR 22 is 200 to 350 ° C. Thereby, the situation where NOx is released downstream of the SCR 22 can be effectively suppressed.
- the NSR catalyst exhibits high NOx purification performance in a temperature environment where the bed temperature is 350 to 450 ° C. For this reason, in the conventional system, the arrangement is set so that the NSR catalyst belongs to such a temperature region.
- the NSR catalyst is arranged in a temperature range of 350 to 450 ° C., it becomes a preferable temperature condition for adhesion of sulfur components. For this reason, under such conditions, sulfur poisoning of the NSR catalyst proceeds in a relatively short time, and the NOx purification performance and NH 3 generation performance are significantly reduced.
- this system is characterized in that an NSR catalyst 202 is provided at the rear stage of the SC 20. That is, in the system of the present embodiment, the NSR catalyst 202 is disposed in a temperature range (500 to 750 ° C.) different from that of the conventional system. In such a temperature range, since the sulfur component hardly adheres to the NSR catalyst 202, it is possible to effectively suppress the situation where sulfur poisoning proceeds in a short time. Therefore, the execution frequency of the sulfur desorption process of the NSR catalyst 202 can be effectively reduced.
- a temperature range 500 to 750 ° C.
- the catalyst bed temperature is already in a high state, so that it can be easily raised to the desorption temperature by exposure to a rich atmosphere. For this reason, the NSR catalyst 202 can be effectively recovered from sulfur poisoning without causing deterioration of fuel consumption and emission.
- the NSR catalyst 202 is disposed in a high temperature region as in the system of the first embodiment described above, the NOx purification efficiency of the NSR catalyst 202 is reduced. Therefore, in the system of the first embodiment, the NSR catalyst 202 is mainly intended to generate NH 3 rather than NOx purification, and the NOx purification is executed in the SCR 22 disposed downstream thereof. As described above, the capacity and characteristics of these catalysts are adjusted. Thereby, even if the NSR catalyst 202 is arranged in a high temperature region, it is possible to effectively suppress the deterioration of NOx emission.
- the degree of progress of sulfur poisoning in the NSR catalyst 202 can be determined, for example, based on the NOx concentration downstream of the SCR 22. This is because when the sulfur poisoning of the NSR catalyst 202 progresses and the amount of NH 3 produced decreases, NH 3 becomes insufficient in the SCR 22, and as a result, the NOx purification rate in the SCR 22 decreases. Therefore, in the system of the present embodiment, when the NOx concentration downstream of the SCR 22 is higher than a predetermined value (for example, 1.4 ppm), it is determined that sulfur poisoning of the NSR catalyst 202 has progressed, and the NSR catalyst It is assumed that the sulfur desorption process 202 is executed.
- a predetermined value for example, 1.4 ppm
- the air-fuel ratio control method From the viewpoint of controllability of the air-fuel ratio, for example, a method of controlling the air-fuel ratio of a predetermined cylinder to a rich air-fuel ratio during lean burn operation is preferable.
- the plurality of cylinders of the internal combustion engine 10 are classified into two cylinder groups (for example, a cylinder group consisting of # 1 and # 3 cylinders and a cylinder group consisting of # 2 and # 4 cylinders).
- the air-fuel ratio of one cylinder group is controlled to a lean air-fuel ratio
- the air-fuel ratio of the other cylinder group is controlled to a rich air-fuel ratio.
- the sensor output value is fed back to the fuel injection amount of each cylinder so that the output of the air-fuel ratio sensor 24 disposed in the exhaust passage 16 becomes an output indicating a slight rich.
- FIG. 3 is a flowchart of a routine in which the ECU 30 executes the sulfur poisoning recovery process of the NSR catalyst 202. Note that the routine of FIG. 3 is repeatedly executed during the lean burn operation of the internal combustion engine 10.
- step 100 it is first determined whether sulfur poisoning of the NSR catalyst 202 is proceeding (step 100). Specifically, it is determined whether or not the NOx sensor value detected by the NOx sensor 26 is equal to or less than a predetermined value (for example, 1.4 ppm). As a result, when the establishment of NOx sensor value ⁇ predetermined value is recognized, it is determined that NH 3 is generated without any problem in the NSR catalyst 202, that is, sulfur poisoning of the NSR catalyst 202 is not progressing. This routine is immediately terminated.
- a predetermined value for example, 1.4 ppm
- NSR is controlled by controlling one cylinder group (for example, # 1 and # 3 cylinders) to a rich air-fuel ratio and the other cylinder group (for example, # 2 and # 4) to a lean air-fuel ratio.
- the air-fuel ratio of the exhaust gas flowing into the catalyst 202 is controlled to a slightly rich target A / F.
- step 104 it is next determined whether or not the NSR catalyst 202 has recovered from sulfur poisoning.
- the NOx sensor value is detected again using the NOx sensor 26.
- the detected NOx sensor value is a predetermined value (1.4 ppm) or less.
- step 104 if NOx sensor value ⁇ predetermined value is not found in step 104, the amount of NH 3 produced in the NSR catalyst 202 has not increased, that is, the NSR catalyst 202 has not yet recovered from sulfur poisoning. If it is determined that there is not, the process shifts to step 102 again, shifts to the next step, and the process for controlling the exhaust air-fuel ratio to be slightly rich is executed again.
- the NSR catalyst 202 since the NSR catalyst 202 is disposed in the predetermined exhaust upstream region (500 to 750 ° C.), sulfur poisoning of the NSR catalyst 202 can be performed in a short time. It is possible to effectively deter progress. Further, according to the arrangement of the NSR catalyst 202 in the system of the first embodiment, the catalyst bed temperature is always at a high temperature. For this reason, when the sulfur desorption process of the NSR catalyst 202 is executed, the temperature can be easily raised to the sulfur desorption temperature, so that deterioration of fuel consumption and system complexity can be effectively avoided.
- the NSR catalyst 202 is arranged at the rear stage of the SC 20 arranged in the high temperature region, but the configuration of the NSR catalyst 202 is not limited to this. That is, as long as the bed temperature of the NSR catalyst 202 is raised to 500 to 750 ° C., the NSR catalyst 202 may be configured separately on the downstream side of the SC 20.
- the exhaust air-fuel ratio is made slightly rich by controlling one cylinder group to a rich air-fuel ratio and the other cylinder group to a lean air-fuel ratio.
- the sulfur poisoning state of the NSR catalyst 202 is detected based on the output signal of the NOx sensor 26, but the sulfur poisoning detection method is not limited to this. That is, when the travel distance from the previous sulfur poisoning recovery process reaches a predetermined distance (for example, 3000 km), the progress of sulfur poisoning may be determined, or from the previous sulfur poisoning recovery process.
- the sulfur adsorption amount of the NSR catalyst 202 may be estimated and determined based on information such as the time, travel distance, exhaust gas amount, air-fuel ratio, and bed temperature.
- the TWC 201 is the “first catalyst” in the first invention
- the NSR catalyst 202 is the “second catalyst” in the first invention
- the SCR 22 is the first catalyst.
- the ECU 30 executes the process of step 100, so that the “determination means” in the fourth aspect of the invention executes the process of step 102.
- the “rich gas introduction means” in the fourth invention is realized.
- the NOx sensor 26 corresponds to the “NOx concentration acquisition means” in the fifth aspect of the invention.
- FIG. 2 Features of Embodiment 2
- a second embodiment of the present invention will be described with reference to FIG.
- the second embodiment can be realized by executing a routine shown in FIG. 4 to be described later using the system shown in FIG.
- the TWC 201 disposed in the front stage of the SC 20 serves as a three-way catalyst that simultaneously purifies the three components of HC, CO, and NOx when the air-fuel ratio of the inflowing exhaust gas is the stoichiometric air-fuel ratio. It has a function.
- the TWC 201 includes noble metals (active points) such as Pt and Pd as catalyst components and an oxygen storage component capable of absorbing and releasing oxygen.
- Pt and Pd active points
- oxygen storage component capable of absorbing and releasing oxygen.
- the oxygen storage component absorbs excess oxygen in the exhaust gas, so that NOx can be reduced and purified.
- the oxygen storage component absorbs and releases oxygen, even if the air-fuel ratio of the exhaust gas flowing into the catalyst varies somewhat from the stoichiometric air-fuel ratio, the three components HC, CO, and NOx are good. Can be purified.
- the purification performance of the three-way catalyst deteriorates over time. It is known that the degree of deterioration of a catalyst is related to the oxygen storage capacity Cmax, which is the maximum amount of oxygen that the catalyst can store. That is, it can be determined that the deterioration of the catalyst progresses as the oxygen storage capacity Cmax decreases. Therefore, the deterioration of the catalyst can be detected by measuring the oxygen storage capacity Cmax of the catalyst.
- the oxygen storage capacity Cmax of the SC 20 is measured by executing active air-fuel ratio control.
- the active air-fuel ratio control is a control for forcibly switching the air-fuel ratio of the internal combustion engine 10 alternately between the rich side and the lean side with the theoretical air-fuel ratio interposed therebetween.
- FIG. 4 is a flowchart of a routine in which the ECU 30 executes the sulfur poisoning recovery process of the NSR catalyst 202. Note that the routine of FIG. 4 is repeatedly executed during the lean burn operation of the internal combustion engine 10.
- step 200 it is first determined whether or not sulfur poisoning of the NSR catalyst 202 is proceeding (step 200).
- step 200 the same processing as in step 100 is executed.
- NH 3 is generated without any problem in the NSR catalyst 202, that is, sulfur poisoning of the NSR catalyst 202 is not progressing. This routine is immediately terminated.
- step 200 determines whether NOx sensor value ⁇ predetermined value is not satisfied in step 200. If NOx sensor value ⁇ predetermined value is not satisfied in step 200, the amount of NH 3 produced in the NSR catalyst 202 is decreased, that is, sulfur poisoning of the NSR catalyst 202 is proceeding.
- the process proceeds to the next step, and it is determined whether it is time to measure the oxygen storage capacity Cmax of the SC 20 (step 202). Specifically, the determination is made based on whether or not the vehicle has traveled a predetermined distance from the previous measurement of the oxygen storage capacity Cmax, whether or not the emission on the downstream side of the SC 20 has deteriorated.
- Step 204 active air-fuel ratio control is performed by shifting the control center of the air-fuel ratio to the rich side.
- target A / F 14.3
- the oxygen storage capacity Cmax of the SC 20 is measured and the sulfur poisoning recovery process of the NSR 202 is performed at the same time.
- the sulfur poisoning recovery process of the NSR catalyst 202 can be executed.
- the NSR catalyst 202 is arranged at the rear stage of the SC 20 arranged in the high temperature region, but the configuration of the NSR catalyst 202 is not limited to this. That is, as long as the bed temperature of the NSR catalyst 202 is raised to 600 to 700 ° C., the NSR catalyst 202 may be configured separately on the downstream side of the SC 20.
- the sulfur poisoning state of the NSR catalyst 202 is detected based on the output signal of the NOx sensor 26, but the sulfur poisoning detection method is not limited to this. That is, when the travel distance from the previous sulfur poisoning recovery process reaches a predetermined distance (for example, 3000 km), the progress of sulfur poisoning may be determined, or from the previous sulfur poisoning recovery process.
- the sulfur adsorption amount of the NSR catalyst 202 may be estimated and determined based on information such as the time, travel distance, exhaust gas amount, air-fuel ratio, and bed temperature.
- the ECU 30 executes the process of step 202, so that the “second determination means” in the ninth aspect of the invention executes the process of step 204.
- the “abnormality diagnosis unit” and the “rich gas introduction unit” in the ninth aspect of the invention are realized.
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Abstract
Description
前記内燃機関の排気通路に配設され、その内部に貴金属が担持された第1の触媒と、
前記第1の触媒の排気下流側に配設され、その内部に貴金属および塩基が担持された第2の触媒と、
前記第2の触媒の下流側の排気通路に配設されたNOx選択還元触媒と、を備え、
前記第2の触媒は、前記排気通路における所定の排気上流領域に配設されていることを特徴とする。
前記第2の触媒は、その動作時の床温が500~750℃となる領域に配設されていることを特徴とする。
前記第1の触媒と前記第2の触媒とは、直列配置で一体化されたタンデム構造であることを特徴とする。
前記第2の触媒の硫黄被毒が進行したか否かを判定する判定手段と、
前記硫黄被毒が進行したと判定された場合に、前記第2の触媒内にリッチガスを導入するリッチガス導入手段と、
を備えることを特徴とする。
前記NOx選択還元触媒の下流側の排気ガスのNOx濃度を取得するNOx濃度取得手段を更に備え、
前記判定手段は、前記NOx濃度が所定濃度よりも高い場合に、前記第2の触媒の硫黄被毒が進行したことを判定することを特徴とする。
前記判定手段は、前記リッチガス導入手段の前回の実行からの走行距離が所定距離よりも長い場合に、前記第2の触媒の硫黄被毒が進行したことを判定することを特徴とする。
前記内燃機関は複数気筒を有する内燃機関であって、
前記リッチガス導入手段は、前記複数気筒を2群に分けた第1,第2の気筒群のうち、前記第1の気筒群の排気空燃比を所定のリッチ空燃比に制御し、前記第2の気筒群の排気空燃比を所定のリーン或いは理論空燃比に制御する空燃比制御手段を含むことを特徴とする。
前記リッチガス導入手段は、前記第2の触媒にスライトリッチの排気ガスを導入することを特徴とする。
前記第1の触媒の異常診断を行うタイミングか否かを判定する第2の判定手段と、
前記第1の触媒の異常診断を行うタイミングである場合に、理論空燃比を制御中心として前記内燃機関の空燃比をリッチ側とリーン側とに交互に強制的に切り替えるアクティブ空燃比制御を実行し、これにより測定した酸素吸蔵容量に基づいて、該第1の触媒の異常診断を実行する異常診断手段と、を更に備え、
前記リッチガス導入手段は、
前記第1の触媒の異常診断を行うタイミングであり、且つ前記第2の触媒の硫黄被毒が進行していると判定された場合に、前記アクティブ空燃比制御における前記制御中心を所定量リッチ方向へ移行させることを特徴とする。
[実施の形態1の構成]
図1は、本発明の実施の形態1の構成を説明するための図である。図1に示すように、本実施の形態のシステムは、内燃機関(エンジン)10を備えている。内燃機関10は多気筒エンジン(図では4気筒)として構成され、各気筒には、筒内に燃料を噴射するための燃料噴射弁12がそれぞれ配置されている。尚、図1のシステムでは直列4気筒エンジンについて説明しているが、V型の多気筒エンジンとして構成されていてもよい。また、図1のシステムでは、燃料噴射弁12として、燃料を筒内に直接噴射する直噴式の燃料噴射弁を用いることとしているが、各気筒のポートに燃料を噴射するポート噴射式の燃料噴射弁でもよい。
(NSR触媒202のNOx浄化機能)
先ず、NSR触媒202のNOx浄化機能について説明する。ECU30は、通常、内燃機関10をリーン空燃比で運転(リーン運転)させる。リーン運転中は、NOx等の酸化剤がHC、CO等の還元剤よりも多量に排出される。このため、TWC201を用いて当該排気ガスを浄化しようとしても、還元剤の不足によって全てのNOxを浄化することができない。そこで、本実施の形態1のシステムは、TWC201の下流側にNSR触媒202を備えることとしている。NSR触媒202は、NOxをBa(NO3)2等の硝酸塩として吸蔵する機能を有している。このため、本実施の形態1のシステムによれば、リーン運転中であっても、該NOxが大気中に放出されてしまう事態を効果的に抑制することができる。
次に、SCR22のNOx浄化機能について説明する。上述したとおり、リッチスパイクの実行によって、NSR触媒202のNOx吸蔵性能を有効に回復させることができる。しかしながら、リッチスパイクが実行されると、該NSR触媒202から脱離したNOxの一部が下流に吹き抜けてしまう。また、上述したとおり、リッチスパイクの実行前にNSR触媒202の下流に吹き抜けてしまうNOxも存在する。これらの吹き抜けNOxがそのまま大気中に放出されてしまうとエミッションの悪化を招いてしまう。
次に、本実施の形態1のシステムの特徴について説明する。上述したとおり、NSR触媒は、床温が350~450℃となる温度環境下において高いNOx浄化性能を発揮する。このため、従来のシステムにおいては、NSR触媒がこのような温度領域に属するように、その配置が設定されている。
a)NSR触媒の床温を700℃程度まで昇温させること
b)NSR触媒内をリッチ雰囲気に晒すこと
次に、図3を参照して、本実施の形態において実行する処理の具体的内容について説明する。図3は、ECU30が、NSR触媒202の硫黄被毒回復処理を実行するルーチンのフローチャートである。尚、図3のルーチンは、内燃機関10のリーンバーン運転中に繰り返し実行される。
[実施の形態2の特徴]
次に、図4を参照して、本発明の実施の形態2について説明する。本実施の形態2は、図1に示すシステムを用いて、後述する図4に示すルーチンを実行することにより実現することができる。
次に、図4を参照して、本実施の形態において実行する処理の具体的内容について説明する。図4は、ECU30が、NSR触媒202の硫黄被毒回復処理を実行するルーチンのフローチャートである。尚、図4のルーチンは、内燃機関10のリーンバーン運転中に繰り返し実行される。
12 燃料噴射弁
14 排気マニホールド
16 排気通路
20 スタート触媒(SC)
201 三元触媒
202 NOx吸蔵還元触媒(NSR触媒)
22 NOx選択還元触媒(SCR)
24 A/Fセンサ
26 NOxセンサ
30 ECU(Electronic Control Unit)
Claims (9)
- リーンバーン運転が可能な内燃機関の排気浄化装置であって、
前記内燃機関の排気通路に配設され、その内部に貴金属が担持された第1の触媒と、
前記第1の触媒の排気下流側に配設され、その内部に貴金属および塩基が担持された第2の触媒と、
前記第2の触媒の下流側の排気通路に配設されたNOx選択還元触媒と、を備え、
前記第2の触媒は、前記排気通路における所定の排気上流領域に配設されていることを特徴とする内燃機関の排気浄化装置。 - 前記第2の触媒は、その動作時の床温が500~750℃となる領域に配設されていることを特徴とする請求項1記載の内燃機関の排気浄化装置。
- 前記第1の触媒と前記第2の触媒とは、直列配置で一体化されたタンデム構造であることを特徴とする請求項1または2記載の内燃機関の排気浄化装置。
- 前記第2の触媒の硫黄被毒が進行したか否かを判定する判定手段と、
前記硫黄被毒が進行したと判定された場合に、前記第2の触媒内にリッチガスを導入するリッチガス導入手段と、
を備えることを特徴とする請求項1乃至3の何れか1項記載の内燃機関の排気浄化装置。 - 前記NOx選択還元触媒の下流側の排気ガスのNOx濃度を取得するNOx濃度取得手段を更に備え、
前記判定手段は、前記NOx濃度が所定濃度よりも高い場合に、前記第2の触媒の硫黄被毒が進行したことを判定することを特徴とする請求項4記載の内燃機関の排気浄化装置。 - 前記判定手段は、前記リッチガス導入手段の前回の実行からの走行距離が所定距離よりも長い場合に、前記第2の触媒の硫黄被毒が進行したことを判定することを特徴とする請求項4または5記載の内燃機関の排気浄化装置。
- 前記内燃機関は複数気筒を有する内燃機関であって、
前記リッチガス導入手段は、前記複数気筒を2群に分けた第1,第2の気筒群のうち、前記第1の気筒群の排気空燃比を所定のリッチ空燃比に制御し、前記第2の気筒群の排気空燃比を所定のリーン或いは理論空燃比に制御する空燃比制御手段を含むことを特徴とする請求項4乃至6の何れか1項記載の内燃機関の排気浄化装置。 - 前記リッチガス導入手段は、前記第2の触媒にスライトリッチの排気ガスを導入することを特徴とする請求項4乃至7の何れか1項記載の内燃機関の排気浄化装置。
- 前記第1の触媒の異常診断を行うタイミングか否かを判定する第2の判定手段と、
前記第1の触媒の異常診断を行うタイミングである場合に、理論空燃比を制御中心として前記内燃機関の空燃比をリッチ側とリーン側とに交互に強制的に切り替えるアクティブ空燃比制御を実行し、これにより測定した酸素吸蔵容量に基づいて、該第1の触媒の異常診断を実行する異常診断手段と、を更に備え、
前記リッチガス導入手段は、
前記第1の触媒の異常診断を行うタイミングであり、且つ前記第2の触媒の硫黄被毒が進行していると判定された場合に、前記アクティブ空燃比制御における前記制御中心を所定量リッチ方向へ移行させることを特徴とする請求項4乃至8の何れか1項記載の内燃機関の排気浄化装置。
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---|---|---|---|---|
WO2013035159A1 (ja) * | 2011-09-06 | 2013-03-14 | トヨタ自動車株式会社 | 内燃機関の排気浄化装置 |
EP2770178B1 (en) * | 2013-02-25 | 2017-04-05 | Cummins Inc. | System and method for sulfur recovery on an SCR catalyst |
JP6278039B2 (ja) * | 2015-12-14 | 2018-02-14 | トヨタ自動車株式会社 | 選択還元型触媒の劣化診断装置 |
DE102017200145B4 (de) * | 2016-01-22 | 2021-12-23 | Ford Global Technologies, Llc | Verfahren zur Überwachung einer Abgasnachbehandlungsanlage, insbesondere eines NOx-Speicher-Katalysators sowie Steuerungseinrichtung für eine Abgasnachbehandlungsanlage und Fahrzeug |
CN105771633A (zh) * | 2016-03-31 | 2016-07-20 | 大唐环境产业集团股份有限公司 | 一种脱硝反应器装置 |
JP7044045B2 (ja) * | 2018-12-07 | 2022-03-30 | トヨタ自動車株式会社 | 内燃機関の排気浄化装置 |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH1130117A (ja) * | 1997-05-12 | 1999-02-02 | Toyota Motor Corp | 内燃機関の排気浄化装置 |
JP2004301036A (ja) * | 2003-03-31 | 2004-10-28 | Ibiden Co Ltd | 触媒コンバータ |
JP2006512529A (ja) * | 2003-01-02 | 2006-04-13 | ダイムラークライスラー・アクチェンゲゼルシャフト | 排気ガス後処理装置及び方法 |
JP2008190461A (ja) * | 2007-02-06 | 2008-08-21 | Mitsubishi Motors Corp | 排ガス浄化装置及び排ガス浄化装置の脱硫方法 |
JP2008286102A (ja) * | 2007-05-17 | 2008-11-27 | Isuzu Motors Ltd | NOx浄化システムの制御方法及びNOx浄化システム |
JP2008303759A (ja) | 2007-06-06 | 2008-12-18 | Toyota Motor Corp | 内燃機関の排気浄化装置 |
JP2008303816A (ja) * | 2007-06-08 | 2008-12-18 | Toyota Motor Corp | 内燃機関の排気浄化装置 |
JP2009097474A (ja) * | 2007-10-18 | 2009-05-07 | Toyota Motor Corp | 触媒劣化診断装置 |
JP2009097471A (ja) * | 2007-10-18 | 2009-05-07 | Toyota Motor Corp | 内燃機関の排気浄化システム |
JP2009114879A (ja) * | 2007-11-02 | 2009-05-28 | Toyota Motor Corp | 内燃機関の排気浄化装置 |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10131588B8 (de) * | 2001-07-03 | 2013-11-14 | Daimler Ag | Betriebsverfahren für eine Abgasnachbehandlungseinrichtung, welche einen Stickoxid-Speicherkatalysator und stromab einen SCR-Katalysator aufweist, sowie Verwendung des SCR-Katalysators zur Entfernung von Schwefelwasserstoff |
US6779337B2 (en) * | 2002-09-20 | 2004-08-24 | Ford Global Technologies, Llc | Hydrogen fueled spark ignition engine |
JP4239765B2 (ja) * | 2003-09-10 | 2009-03-18 | トヨタ自動車株式会社 | 内燃機関の排気浄化触媒制御方法及び排気浄化触媒制御装置 |
US7490464B2 (en) * | 2003-11-04 | 2009-02-17 | Basf Catalysts Llc | Emissions treatment system with NSR and SCR catalysts |
US7063642B1 (en) * | 2005-10-07 | 2006-06-20 | Eaton Corporation | Narrow speed range diesel-powered engine system w/ aftertreatment devices |
US7533523B2 (en) * | 2006-11-07 | 2009-05-19 | Cummins, Inc. | Optimized desulfation trigger control for an adsorber |
EP1939420A1 (de) * | 2006-12-30 | 2008-07-02 | Umicore AG & Co. KG | Verfahren zum Entschwefeln von Stickoxid-Speicherkatalysatoren in der Abgasanlage eines Magermotors |
US7718150B2 (en) * | 2007-04-17 | 2010-05-18 | Ford Global Technologies, Llc | Reverse platinum group metal zoned lean NOx trap system and method of use |
US7797929B2 (en) * | 2007-05-21 | 2010-09-21 | Ford Global Technologies, Llc | Low temperature emission control |
JP4821737B2 (ja) * | 2007-08-21 | 2011-11-24 | トヨタ自動車株式会社 | 内燃機関の排気浄化装置 |
US8007404B2 (en) * | 2007-12-12 | 2011-08-30 | Eaton Corporation | Transmission shift signal for aftertreatment device control |
US7926263B2 (en) * | 2007-12-20 | 2011-04-19 | GM Global Technology Operations LLC | Regeneration system and method for exhaust aftertreatment devices |
JP5062529B2 (ja) * | 2008-02-28 | 2012-10-31 | トヨタ自動車株式会社 | 触媒の劣化を診断するための装置及び方法 |
-
2010
- 2010-08-23 JP JP2012530432A patent/JP5534013B2/ja not_active Expired - Fee Related
- 2010-08-23 CN CN2010800687019A patent/CN103080490A/zh active Pending
- 2010-08-23 US US13/818,394 patent/US20130152552A1/en not_active Abandoned
- 2010-08-23 EP EP10856385.9A patent/EP2610451A4/en not_active Withdrawn
- 2010-08-23 WO PCT/JP2010/064182 patent/WO2012025976A1/ja active Application Filing
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH1130117A (ja) * | 1997-05-12 | 1999-02-02 | Toyota Motor Corp | 内燃機関の排気浄化装置 |
JP2006512529A (ja) * | 2003-01-02 | 2006-04-13 | ダイムラークライスラー・アクチェンゲゼルシャフト | 排気ガス後処理装置及び方法 |
JP2004301036A (ja) * | 2003-03-31 | 2004-10-28 | Ibiden Co Ltd | 触媒コンバータ |
JP2008190461A (ja) * | 2007-02-06 | 2008-08-21 | Mitsubishi Motors Corp | 排ガス浄化装置及び排ガス浄化装置の脱硫方法 |
JP2008286102A (ja) * | 2007-05-17 | 2008-11-27 | Isuzu Motors Ltd | NOx浄化システムの制御方法及びNOx浄化システム |
JP2008303759A (ja) | 2007-06-06 | 2008-12-18 | Toyota Motor Corp | 内燃機関の排気浄化装置 |
JP2008303816A (ja) * | 2007-06-08 | 2008-12-18 | Toyota Motor Corp | 内燃機関の排気浄化装置 |
JP2009097474A (ja) * | 2007-10-18 | 2009-05-07 | Toyota Motor Corp | 触媒劣化診断装置 |
JP2009097471A (ja) * | 2007-10-18 | 2009-05-07 | Toyota Motor Corp | 内燃機関の排気浄化システム |
JP2009114879A (ja) * | 2007-11-02 | 2009-05-28 | Toyota Motor Corp | 内燃機関の排気浄化装置 |
Non-Patent Citations (1)
Title |
---|
See also references of EP2610451A4 |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013175604A1 (ja) * | 2012-05-24 | 2013-11-28 | トヨタ自動車株式会社 | 内燃機関の排気浄化装置 |
US20150285118A1 (en) * | 2012-05-24 | 2015-10-08 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purification apparatus for an internal combustion engine |
JPWO2013175604A1 (ja) * | 2012-05-24 | 2016-01-12 | トヨタ自動車株式会社 | 内燃機関の排気浄化装置 |
CN104334846A (zh) * | 2012-06-07 | 2015-02-04 | 丰田自动车株式会社 | 发动机系统 |
Also Published As
Publication number | Publication date |
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CN103080490A (zh) | 2013-05-01 |
JPWO2012025976A1 (ja) | 2013-10-28 |
US20130152552A1 (en) | 2013-06-20 |
EP2610451A4 (en) | 2014-10-22 |
JP5534013B2 (ja) | 2014-06-25 |
EP2610451A1 (en) | 2013-07-03 |
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