US20100132337A1 - Exhaust gas purification device for internal combustion engine - Google Patents

Exhaust gas purification device for internal combustion engine Download PDF

Info

Publication number
US20100132337A1
US20100132337A1 US12/530,842 US53084208A US2010132337A1 US 20100132337 A1 US20100132337 A1 US 20100132337A1 US 53084208 A US53084208 A US 53084208A US 2010132337 A1 US2010132337 A1 US 2010132337A1
Authority
US
United States
Prior art keywords
fuel
exhaust gas
filter
ozone
nox
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US12/530,842
Other languages
English (en)
Inventor
Hirohito Hirata
Masaya Ibe
Hiroyuki Matsubara
Masaya Kamada
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Motor Corp
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA reassignment TOYOTA JIDOSHA KABUSHIKI KAISHA ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KAMADA, MASAYA, MATSUBARA, HIROYUKI, HIRATA, HIROHITO, IBE, MASAYA
Publication of US20100132337A1 publication Critical patent/US20100132337A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • 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
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/023—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles
    • F01N3/025—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles using fuel burner or by adding fuel to exhaust
    • F01N3/0253—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles using fuel burner or by adding fuel to exhaust adding fuel to exhaust gases
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/42—Auxiliary equipment or operation thereof
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9445—Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC]
    • 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
    • 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
    • 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
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2251/00—Reactants
    • B01D2251/10—Oxidants
    • B01D2251/104—Ozone
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2251/00—Reactants
    • B01D2251/20—Reductants
    • B01D2251/208—Hydrocarbons
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/10—Noble metals or compounds thereof
    • B01D2255/102—Platinum group metals
    • B01D2255/1021—Platinum
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/204—Alkaline earth metals
    • B01D2255/2042—Barium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/90—Physical characteristics of catalysts
    • B01D2255/91—NOx-storage component incorporated in the catalyst
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2258/00—Sources of waste gases
    • B01D2258/01—Engine exhaust gases
    • B01D2258/012—Diesel engines and lean burn gasoline engines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2279/00—Filters adapted for separating dispersed particles from gases or vapours specially modified for specific uses
    • B01D2279/30—Filters adapted for separating dispersed particles from gases or vapours specially modified for specific uses for treatment of exhaust gases from IC Engines
    • 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
    • F01N2240/00—Combination or association of two or more different exhaust treating devices, or of at least one such device with an auxiliary device, not covered by indexing codes F01N2230/00 or F01N2250/00, one of the devices being
    • F01N2240/38—Combination or association of two or more different exhaust treating devices, or of at least one such device with an auxiliary device, not covered by indexing codes F01N2230/00 or F01N2250/00, one of the devices being an ozone (O3) generator, e.g. for adding ozone after generation of ozone from air
    • 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
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/02—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor
    • F01N2560/025—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor for measuring or detecting O2, e.g. lambda sensors
    • 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
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/02—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor
    • F01N2560/026—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor for measuring or detecting NOx
    • 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
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/08—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being a pressure sensor
    • 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
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/14—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics having more than one sensor of one kind
    • 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
    • F01N2610/00—Adding substances to exhaust gases
    • 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
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/03—Adding substances to exhaust gases the substance being hydrocarbons, e.g. engine fuel
    • 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
    • F01N2900/00—Details of electrical control or of the monitoring of the exhaust gas treating apparatus
    • F01N2900/06—Parameters used for exhaust control or diagnosing
    • F01N2900/16—Parameters used for exhaust control or diagnosing said parameters being related to the exhaust apparatus, e.g. particulate filter or catalyst
    • F01N2900/1614—NOx amount trapped in catalyst
    • 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

Definitions

  • the present invention relates generally to exhaust gas purification devices for internal combustion engines, and more particularly, to an exhaust gas purification device including an NOx storage reduction catalyst and a particulate filter.
  • exhaust gas purification devices with a filter and an NOx storage reduction catalyst arranged in that order from upstream toward downstream on the exhaust passages in internal combustion engines, especially, diesel engines, are traditionally known (the NOx storage reduction catalyst is hereinafter referred to as the NSR catalyst).
  • the NOx storage reduction catalyst is hereinafter referred to as the NSR catalyst.
  • the particulates contained in exhaust gas can be captured with the filter.
  • NOx whose purification becomes insufficient under a lean atmosphere can be captured with the NSR catalyst.
  • a process for removing the captured particulates from the filter (hereinafter, this process is referred to as the regeneration of the filter) is needed to prevent increases in exhaust resistance due to filter clogging.
  • a known way to remove particulates from such a filter is by adding fuel to exhaust gas upstream relative to the filter and increasing the temperature of the exhaust gas flowing into the filter. Enhancing the temperature of the exhaust gas allows the particulates to be burned by utilizing the heat.
  • the above exhaust gas purification devices also require a process for removing stored NOx from the NSR catalyst (hereinafter, this process is referred to as the regeneration of the NSR catalyst).
  • a known way to remove stored NOx from an NSR catalyst is by adding fuel to exhaust gas upstream relative to the NSR catalyst and making rich the air-fuel ratio of the exhaust gas flowing into the NSR catalyst. Making the exhaust gas rich in air-fuel ratio allows the stored NOx to be reduced and purified by means of the HC or CO contained in the exhaust gas. The reduction of the stored NOx by the HC or the CO is a reaction occurring when the NSR catalyst is sufficiently warmed. Accordingly, not all chemical potentials of the fuel added to the exhaust gas during the regeneration of the NSR catalyst will be used to reduce the stored NOx. Instead, one portion or a large portion of the chemical potential will be used to heat the NSR catalyst.
  • Patent Document 1 JP-A-2002-89240
  • Patent Document 2 JP-A-2005-538295
  • Patent Document 3 JP-A-2006-522272
  • Patent Document 4 JP-A-2000-297633
  • Patent Document 5 JP-A-2002-188432
  • the fuel efficiency of the internal combustion engine therefore, can be correspondingly improved if the fuel consumption can be reduced.
  • One method of achieving this is by utilizing the heat generated by the regeneration of the filter for regenerating the NSR catalyst. During the regeneration of the filter, the combustion of the added fuel generates heat and at the same time, the combustion of particulates also generates heat. If such heat is used to warm the NSR catalyst, only the amount of fuel consumed to chemically reduce stored NOx will be required as the fuel consumption for the regeneration of the NSR catalyst.
  • the present invention has been made for solving the above problem, and an object of the invention is to provide an exhaust gas purification device including an NOx storage reduction catalyst and a particulate filter, in the purification device of which, the NOx storage reduction catalyst can fully utilize its original capability to store NOx.
  • a first aspect of the present invention is an exhaust gas purification device for an internal combustion engine, comprising:
  • an NOx storage reduction catalyst disposed on an exhaust passage of the internal combustion engine
  • a filter disposed upstream relative to the NOx storage reduction catalyst, the filter being used to capture particulates contained in exhaust gas;
  • a second aspect of the present invention is the exhaust gas purification device for the internal combustion engine according to the first aspect of the present invention, further comprising:
  • a third aspect of the present invention is the exhaust gas purification device for the internal combustion engine according to the first aspect of the present invention, wherein the fuel supply means is adapted to:
  • a fourth aspect of the present invention is the exhaust gas purification device for the internal combustion engine according to the second aspect of the present invention, wherein:
  • the fuel supply means executes fuel supply while controlling a supply quantity of the fuel such that an air-fuel ratio of the exhaust gas flowing into the filter will be lean;
  • the second means for supplying the fuel executes a predetermined period of fuel supply while controlling a supply quantity of the fuel such that the air-fuel ratio of the exhaust gas flowing into the NOx storage reduction catalyst will be rich.
  • supplying ozone such that the ozone will be mixed with the exhaust gas flowing into the NOx storage reduction catalyst allows accelerated oxidation of any NOx substances contained in the exhaust gas, and hence, accelerated storage of the NOx into the NOx storage reduction catalyst.
  • the amount of ozone to be supplied is controlled for a molar quantity of the ozone in the exhaust gas to be larger than a molar quantity of NO, nitrogen oxides of an order higher than that of NO 2 , such as NO 2 and N 2 O 5 , can be generated.
  • NO 2 and N 2 O 5 nitrogen oxides of an order higher than that of NO 2 , such as NO 2 and N 2 O 5 .
  • HNO 3 if moisture is present. Generating the above nitrogen oxides of a higher order enables the NOx storage reduction catalyst to further accelerate its internal NOx storage reaction.
  • the fuel can be supplied to the NOx storage reduction catalyst without being passed through the filter.
  • the fuel can also be simultaneously supplied in divided form to two sections, namely, an upstream side of the filter and that of the NOx storage reduction catalyst. In this way, the fuel can be supplied in any one or more of selectable plural forms to make more effective use of the fuel.
  • the filter can be regenerated and at the same time, the heat generated during the regeneration of the filter can be used to warm the NOx storage reduction catalyst.
  • the NOx storage reduction catalyst can be regenerated efficiently by supplying the exhaust gas of a rich air-fuel ratio to the NOx storage reduction catalyst that has been warmed to high enough a temperature.
  • the filter can be regenerated and at the same time, the heat generated during the regeneration of the filter can be used to warm the NOx storage reduction catalyst. Additionally, a lean atmosphere in the filter and a rich atmosphere in the NOx storage reduction catalyst can both be created at the same time by supplying the fuel in divided form to two different sections. This makes the regeneration of the NOx storage reduction catalyst simultaneously achievable with that of the filter, thus making more effective use of the heat generated during the regeneration of the filter.
  • FIG. 1 is a diagram illustrating an exhaust gas purification device configuration in a first embodiment of the present invention.
  • FIG. 2 is a flowchart representing a routine executed in the first embodiment of the present invention.
  • FIG. 3 is a diagram illustrating an exhaust gas purification device configuration in a second embodiment of the present invention.
  • FIG. 4 is a flowchart representing a routine executed in the second embodiment of the present invention.
  • FIG. 1 is a diagram illustrating an exhaust gas purification device configuration in a first embodiment of the invention.
  • the exhaust gas purification device configuration in the first embodiment is described below using FIG. 1 .
  • the exhaust gas purification device of the first embodiment includes a diesel particulate filter (hereinafter, referred to as DPF) 40 and a catalytic converter 20 , in an exhaust passage 12 of a diesel engine (hereinafter, referred to simply as engine) 10 .
  • the catalytic converter 20 is disposed downstream relative to the DPF 40 .
  • exhaust gas from the engine 10 first have any particulates removed by the DPF 40 , and then have any NOx, HC, and CO substances purified by the catalytic converter 20 before the exhaust gas are released to the atmosphere.
  • a fuel injector 42 is installed near an inlet of the DPF 40 on the exhaust passage 12 , and the same fuel as used for operating the engine 10 is injected from the fuel injector 42 .
  • NSR catalyst 22 An NOx storage reduction catalyst (hereinafter, referred to as NSR catalyst) 22 is accommodated in the catalytic converter 20 .
  • a noble metal such as platinum Pt, and BaCO 3 are supported on a ceramic support to constitute the NSR catalyst 22 , with Pt functioning as an active site that simultaneously activates an oxidation reaction of CO, HC and a reducing reaction of NOx, and BaCO 3 functioning as an NOx-retaining substance to occlude the NOx contained in the exhaust gas in the form of a nitrate. More specifically, NOx is occluded as Ba(NO 3 ) 2 in BaCO 3 . The stored Ba(NO 3 ) 2 is reduced and decomposed primarily under a rich state of the exhaust gas.
  • the NOx-retaining substance however, not only occludes NOx, but may also adsorb NOx. For this reason, the “retaining” action of the NOx-retaining substance connotes “adsorbing” the NOx as well as “occluding” the NOx.
  • a gas injection port 32 is provided at an upstream side of the NSR catalyst 22 within the catalytic converter 20 .
  • the gas injection port 32 is connected to an ozone feeder 30 .
  • the ozone feeder 30 contains an ozonizer that creates ozone by use of air obtained from an air suction port 34 . Further detailed description of the ozonizer is omitted herein since various techniques concerning its configuration and functionality are already known.
  • the ozone feeder 30 supplies internally created ozone from the gas injection port 32 to the inside of the catalytic converter 20 . Inside the catalytic converter 20 , the ozone supplied from the ozone feeder 30 gets mixed with the exhaust gas flowing in through the exhaust passage 12 , and then the mixed gas flows into the NSR catalyst 22 .
  • the exhaust gas purification device of the present embodiment includes a plurality of sensors for obtaining information on states of the purification device. More specifically, the DPF 40 has a differential pressure sensor 52 that outputs a signal commensurate with a differential pressure between an inlet and outlet of the DPF. An air-fuel ratio sensor 54 that outputs a signal commensurate with an air-fuel ratio of the exhaust gas is mounted near the outlet of the DPF 40 on the exhaust passage 12 . Also, an NOx sensor 56 that detects NOx is mounted near an outlet of the catalytic converter 20 on the exhaust passage 12 .
  • the exhaust gas purification device of the present embodiment also includes a controller 50 that controls operation of the purification device.
  • the above-described ozone feeder 30 and fuel injector 42 are connected to an output section of the controller 50 .
  • the above-described sensors 52 , 54 , 56 are connected to an input section of the controller 50 .
  • Information on operating parameters and operating states of the engine 10 is also input to the input section of the controller 50 .
  • the controller 50 controls the ozone feeder 30 and the fuel injector 42 in accordance with a predetermined control program.
  • the NOx contained in the exhaust gas can be stored using the NSR catalyst 22 .
  • the present embodiment utilizes ozone to improve the NSR catalyst 22 in NOx storage capability.
  • the engine 10 activates the ozone feeder 30 to supply ozone to the catalytic converter 20 .
  • the NOx contained in the exhaust gas will be oxidized by a gas-phase reaction. More specifically, the NOx and the ozone will react upon each other to develop the reactions shown in reaction formulae (1) to (3) that follow.
  • Reaction formula (3) is shown only with an arrow that indicates a rightward reaction, but such a leftward reaction as enclosed in brackets below can also occur.
  • the NOx-retaining substance occludes the resulting nitrogen oxides of a high order (or HNO 3 generated by reactions of these nitrogen oxides with water).
  • the NOx occlusion occurring with the NOx-retaining substance is thus achieved.
  • NO 3 when converted into a nitrate such as Ba(NO 3 ) 2 , NO 3 is occluded by an NOx occluding material.
  • reaction formulae (1) to (3) therefore, when ozone is added to exhaust gas, the high-order nitrogen oxides that the NOx-retaining substance easily occludes can be created efficiently. That is to say, the NOx storage capability of the NSR catalyst 22 can be enhanced.
  • the quantity of ozone to be supplied is controlled so that a molar ratio of the ozone to NO is greater than 1 in a mixture of the exhaust gas and the ozone.
  • the control of the ozone supply quantity is conducted by the controller 50 .
  • the controller 50 estimates and calculates the quantity of NO in the exhaust gas and controls the ozone feeder 30 to supply an appropriate quantity of ozone according to the estimated quantity of NO.
  • the quantity of ozone to be supplied is preferably controlled to obtain a molar ratio of at least 2 of the ozone to the NO in the mixed gas.
  • This alternative method allows a large portion of the NO to be oxidized into NO 3 and N 2 O 5 , and the quantity of NOx storage into the NSR catalyst 22 to be increased remarkably.
  • the regeneration of the DPF 40 is a process for preventing increases in exhaust resistance due to clogging of the DPF 40 , and this process is executed upon detection of the clogging of the DPF 40 by the differential pressure sensor 52 . More specifically, combustion heat of the fuel injected from the fuel injector 42 heats the DPF 40 . Particulates that the DPF 40 has captured are burned by the heating of the DPF, and removed therefrom. Since oxygen is needed to burn the particulates, an injection quantity of the fuel from the fuel injector 42 is controlled so that the exhaust gas flowing into the DPF 40 will be a lean air-fuel ratio.
  • the regeneration of the NSR catalyst 22 is a process for recovering the NOx storage capability of the NSR catalyst 22 by removing stored NOx from the NSR catalyst 22 . More specifically, the NSR catalyst 22 is heated and the air-fuel ratio of the exhaust gas flowing thereinto is temporarily enhanced for a rich air-fuel ratio. The stored NOx within the NSR catalyst 22 is reduced by the HC and CO contained in the exhaust gas, and then removed from the NSR catalyst 22 . The air-fuel ratio of the exhaust gas flowing into the NSR catalyst 22 can be adjusted according to the particular fuel injection quantity of the fuel injector 42 .
  • Heat that has been generated during the regeneration of the DPF 40 can be utilized to regenerate the NSR catalyst 22 .
  • combustion of the fuel injected from the fuel injector 42 generates heat and at the same time, the combustion of the particulates also generates heat.
  • Much of the fuel injected from the fuel injector 42 can be used for the reduction of the stored NOx if such heat is utilized to heat the NSR catalyst 22 .
  • the exhaust gas purification device of the present embodiment allows the NOx storage quantity of the NSR catalyst 22 to be increased by utilizing ozone, and thus the regenerating period of the NSR catalyst 22 to be extended.
  • FIG. 2 is a flowchart representing a routine executed by the controller 50 in the present embodiment.
  • the above-described addition of ozone and regeneration of the DPF 40 and NSR catalyst 22 are both executed in accordance with the routine shown in FIG. 2 .
  • step S 100 of the routine shown in FIG. 2 ozone is created from air by the ozone feeder 30 and then the ozone is added to exhaust gas.
  • a gas-phase reaction with the ozone in the catalytic converter 20 accelerates the oxidation of the NOx in the exhaust gas, and hence, storage of the NOx into the NSR catalyst 22 .
  • step S 102 Whether the clogging of the DPF 40 is detected by the differential pressure sensor 52 is judged in step S 102 . If the clogging of the DPF 40 is detected, process control advances to step S 104 to execute the regeneration of the DPF 40 .
  • step S 104 fuel injection from the fuel injector 42 is executed and fuel is added to the exhaust gas flowing into the DPF 40 .
  • the fuel injection quantity of the fuel injector 42 is controlled so that the exhaust gas flowing into the DPF 40 will be a lean air-fuel ratio.
  • An output signal from the air-fuel ratio sensor 54 is fed back during the control of the fuel injection quantity.
  • the fuel that has been injected from the fuel injector 42 is burned upon reacting with the oxygen in the exhaust gas, and the resulting heat creates a high-temperature atmosphere in the DPF 40 .
  • the particulates on the DPF 40 are burned upon reacting with excess oxygen present in the exhaust gas, and are progressively removed from the DPF 40 .
  • step S 106 Whether the clogging of the DPF 40 is detected by the differential pressure sensor 52 is re-judged in step S 106 .
  • Process step S 104 is continued if the clogging of the DPF 40 is re-detected or still remains detected. Conversely if the clogged state of the DPF 40 is cleared, the regeneration thereof terminates and process control advances to step S 108 to execute the regeneration of the NSR catalyst 22 .
  • step S 108 the creation of ozone by the ozone feeder 30 is stopped and the addition of the ozone to the exhaust gas is also stopped.
  • next step S 110 fuel injection from the fuel injector 42 is continued and fuel is added to the exhaust gas flowing into the DPF 40 .
  • a fuel injection quantity of the fuel injector 42 at this time is controlled so that the exhaust gas flowing into the DPF 40 will be a rich air-fuel ratio.
  • An output signal from the air-fuel ratio sensor 54 is fed back during the control of the fuel injection quantity.
  • the NOx stored within the NSR catalyst 22 is reduced by the HC and CO contained in the exhaust gas, and then removed from the NSR catalyst 22 progressively.
  • the heat generated by the combustion of the added fuel and stored particulates raises a temperature of the exhaust gas flowing into the catalytic converter 20 .
  • the high-temperature exhaust gas then warm the NSR catalyst 22 and the catalyst temperature upon completion of the regeneration of the DPF 40 rises to, or nearly to, a temperature level required for the regeneration thereof. Therefore, the amount of fuel consumed to heat the NSR catalyst 22 for the regeneration thereof is saved and much of the fuel injected from the fuel injector 42 can be used to reduce the stored NOx.
  • Fuel addition for regenerating the NSR catalyst 22 is executed only for a required regenerating period calculated from the NOx storage quantity existing immediately before the regeneration.
  • the NOx storage quantity can be estimated and calculated from counts of a cumulative operating period and/or cumulative traveling distance from a previous regenerating process for the NSR catalyst 22 .
  • process control proceeds to step S 112 to stop the addition of fuel from the fuel injector 42 . This completes the regeneration of the DPF 40 and then completes that of the NSR catalyst 22 as well.
  • step S 102 control is transferred to step S 114 for a next judgment. Whether NOx is detected by the NOx sensor 56 is judged in step S 114 . If no NOx is detected, control is returned to the judgment in step S 102 . Subsequently, either step S 102 or S 114 is repeated until a positive judgment has been conducted therein.
  • the NOx detected by the NOx sensor 56 is that which has not been stored into the NSR catalyst 22 .
  • Upon saturation of the quantity of NOx storage in the NSR catalyst 22 non-stored NOx flows out in the downstream direction.
  • control proceeds to step S 116 , in which step, the regeneration of the NSR catalyst 22 is then executed.
  • step S 116 the creation of ozone by the ozone feeder 30 is stopped and the addition of the ozone to the exhaust gas is also stopped.
  • next step S 118 fuel injection from the fuel injector 42 is executed and fuel is added to the exhaust gas flowing into the DPF 40 .
  • the fuel injection quantity of the fuel injector 42 is controlled so that the exhaust gas flowing into the DPF 40 will be a rich air-fuel ratio.
  • An output signal from the air-fuel ratio sensor 54 is fed back during the control of the fuel injection quantity.
  • the fuel that has been injected from the fuel injector 42 is burned upon reacting with the oxygen in the exhaust gas, and the resulting heat warms the exhaust gas.
  • excess fuel is left intact in the exhaust gas, passes through the DPF 40 , and flows into the NSR catalyst 22 .
  • the high-temperature exhaust gas of a rich air-fuel ratio flows into the NSR catalyst 22 , the NOx stored therein is reduced by the HC and CO contained in the exhaust gas, and is progressively removed from the NSR catalyst 22 .
  • Fuel addition for the regeneration of the NSR catalyst 22 is executed only for the required regenerating period calculated from the NOx storage quantity existing immediately before the regeneration.
  • the NOx storage quantity can be estimated and calculated from counts of the cumulative operating period and/or cumulative traveling distance from the previous regenerating process for the NSR catalyst 22 .
  • process control proceeds to step S 120 to stop the addition of fuel from the fuel injector 42 . This completes the regeneration of the NSR catalyst 22 .
  • supply of ozone to the inside of the catalytic converter 20 by the ozone feeder 30 during lean-burn operation of the engine 10 allows the oxidation of the NOx in the exhaust gas to be accelerated and thus the quantity of NOx storage into the NSR catalyst 22 to be increased.
  • An increase in the quantity of NOx storage into the NSR catalyst 22 extends the regenerating period thereof, with a result that the heat generated during the regeneration of the DPF 40 will have more chances to be utilized for the regeneration of the NSR catalyst 22 .
  • the exhaust gas purification device of the present embodiment therefore, can suppress consumption of the fuel required for the regeneration of the NSR catalyst 22 and DPF 40 , and thereby improve fuel efficiency of the engine 10 .
  • FIG. 3 is a diagram illustrating an exhaust gas purification device configuration in a second embodiment of the invention.
  • the exhaust gas purification device configuration in the present embodiment is described below using FIG. 3 .
  • sections and components common to those of the exhaust gas purification device according to the first embodiment are each assigned the same reference number.
  • description of the common sections and components is omitted, with descriptive focus placed only upon configurational differences relative to the first embodiment.
  • the exhaust gas purification device of the present embodiment has a fuel injector 44 between the DFP 40 and catalytic converter 20 on the exhaust passage 12 .
  • the fuel injector 44 as with the fuel injector 42 , injects the same fuel as used for operating the engine 10 .
  • the exhaust gas purification device of the present embodiment further has an air-fuel ratio sensor 58 disposed downstream relative to the fuel injector 44 , near an inlet of the catalytic converter 20 , the air-fuel ratio sensor 58 being adapted to output a signal according to a particular air-fuel ratio of exhaust gas.
  • the fuel injector 44 is installed between the two air-fuel ratio sensors 54 , 58 .
  • the ozone feeder 30 and the two fuel injectors 42 and 44 are connected to the output section of the controller 50 .
  • the plurality of sensors 52 , 54 , 56 and 58 are connected to the input section of the controller 50 .
  • information on operating parameters and operating states of the engine 10 is input to the input section of the controller 50 .
  • the controller 50 controls the ozone feeder 30 and the fuel injectors 42 and 44 in accordance with the predetermined control program.
  • One of the operational differences between the present embodiment and the first embodiment exists in that the DPF 40 and the NSR catalyst 22 are simultaneously regenerated in the present embodiment. As described in the first embodiment, regenerating the DPF 40 requires adding fuel while ensuring a lean air-fuel ratio state of the exhaust gas flowing into the DPF 40 . Regenerating the NSR catalyst 22 , on the other hand, requires ensuring a rich air-fuel ratio state of the exhaust gas flowing into the NSR catalyst 22 . In the device configuration of the first embodiment, since it has been impossible to make the device satisfy the above two requirements at the same time, the regeneration of the NSR catalyst 22 has been conducted following completion of that of the DPF 40 .
  • the exhaust gas purification device configuration in the second embodiment makes it possible to supply fuel to the NSR catalyst 22 without passing the fuel through the DPF 40 .
  • Fuel can also be supplied in divided form to two sections at the same time, that is, an upstream side of the DPF 40 and that of the NSR catalyst 22 .
  • the fuel injection quantities of the fuel injectors 42 and 44 are controlled, as appropriate, to supply the exhaust gas of a rich air-fuel ratio to the NSR catalyst 22 while supplying the exhaust gas of a lean air-fuel ratio to the DPF 40 .
  • the DPF 40 and the NSR catalyst 22 can be regenerated simultaneously.
  • FIG. 4 is a flowchart representing the routine executed by the controller 50 in the present embodiment.
  • the above-described addition of ozone and regeneration of the DPF 40 and NSR catalyst 22 are both executed in accordance with the routine shown in FIG. 4 .
  • step S 200 of the routine shown in FIG. 4 ozone is created from air by the ozone feeder 30 and then the ozone is added to exhaust gas.
  • a gas-phase reaction with the ozone in the catalytic converter 20 accelerates the oxidation of the NOx in the exhaust gas, and hence, storage of the NOx into the NSR catalyst 22 .
  • step S 202 Whether the clogging of the DPF 40 is detected by the differential pressure sensor 52 is judged in step S 202 . If the clogging of the DPF 40 is detected, process control advances to step S 204 , in which step, the creation of ozone by the ozone feeder 30 is then stopped and the addition of the ozone to the exhaust gas is also stopped. Process control further advances to step S 206 to execute the regeneration of the DPF 40 .
  • step S 206 fuel injection from the fuel injector 42 is executed and fuel is added to the exhaust gas flowing into the DPF 40 .
  • a fuel injection quantity of the fuel injector 42 is controlled so that the exhaust gas flowing into the DPF 40 will be of a lean air-fuel ratio.
  • An output signal from the air-fuel ratio sensor 54 is fed back during the control of the fuel injection quantity.
  • the fuel that has been injected from the fuel injector 42 is burned upon reacting with the oxygen in the exhaust gas, and the resulting heat creates a high-temperature atmosphere in the DPF 40 .
  • particulates present on the DPF 40 are burned upon reacting with excess oxygen present in the exhaust gas, and are progressively removed from the DPF 40 .
  • step S 208 Whether the regenerating process for the NSR catalyst 22 is necessary is judged in next step S 208 . This judgment is based upon the quantity of NOx stored at up to a current point of time.
  • the NOx storage quantity can be estimated and calculated from counts of the cumulative operating period and/or cumulative traveling distance from the previous regenerating process for the NSR catalyst 22 . If the estimated quantity of NOx storage is in excess of a predetermined reference level, the regenerating process for the NSR catalyst 22 is judged to be necessary. In this case, control is transferred to step S 210 , in which, the regeneration of the NSR catalyst 22 is executed simultaneously with that of the DPF 40 .
  • step S 210 fuel injection by the fuel injector 44 is also executed downstream relative to the DPF 40 , and fuel is added to the exhaust gas flowing into the NSR catalyst 22 .
  • a fuel injection quantity of the fuel injector 44 is controlled so that the exhaust gas flowing into the NSR catalyst 22 will be a rich air-fuel ratio. A large amount of fuel does not need to be injected from the fuel injector 44 at this time since fuel addition by the fuel injector 42 is also continued at the upstream side of the DPF 40 .
  • An output signal from the air-fuel ratio sensor 58 is fed back during the control of the fuel injection quantity of the fuel injector 44 .
  • the NOx stored within the NSR catalyst 22 is reduced by the HC and CO contained in the exhaust gas, and is progressively removed from the NSR catalyst 22 .
  • the exhaust gas that have passed through the DPF 40 are heated to a high temperature by the combustion of the added fuel and that of the particulates. Since the heat of the high-temperature exhaust gas can be used during the regeneration of the NSR catalyst 22 , there is no need to burn new fuel for heating the NSR catalyst 22 , or even if new fuel needs burning, it is enough just to burn a slight amount of fuel. Much of the fuel injected from the fuel injector 44 , therefore, can be used to reduce stored NOx.
  • Fuel addition by the fuel injector 44 for the regeneration of the NSR catalyst 22 is executed only for the required regenerating period calculated from the NOx storage quantity existing immediately before the regeneration.
  • the NOx storage quantity can be estimated and calculated from counts of the cumulative operating period and/or cumulative traveling distance from the previous regenerating process for the NSR catalyst 22 .
  • process control proceeds to step S 212 , in which step, the addition of fuel by the fuel injector 44 is then stopped. This completes the regeneration of the NSR catalyst 22 .
  • step S 214 Completion of the regeneration of the NSR catalyst 22 is followed by a re-judgment in step S 214 . Whether the clogging of the DPF 40 is detected by the differential pressure sensor 52 is re-judged in step S 214 . Process step S 206 is continued if the clogging of the DPF 40 is re-detected or still remains detected. After the regeneration of the NSR catalyst 22 , it is judged in step S 208 that the regenerating process is unnecessary. Process steps S 210 and S 212 are therefore skipped and the judgment in step S 214 follows.
  • step S 214 If, in step S 214 , the clogged state of the DPF 40 is judged to be cleared, process control advances to step S 216 .
  • step S 216 the addition of fuel at the upstream side of the DPF 40 by the fuel injector 42 is stopped. This completes the regeneration of the DPF 40 .
  • step S 202 control is transferred to step S 218 for a next judgment. Whether NOx is detected by the NOx sensor 56 is judged in step S 218 . If no NOx is detected, control is returned to the judgment in step S 202 . Subsequently, either step S 202 or S 218 is repeated until a positive judgment has been conducted therein.
  • step S 220 If NOx is detected by the NOx sensor 56 , control proceeds to step S 220 , in which step, the regeneration of the NSR catalyst 22 is then executed.
  • step S 220 the creation of ozone by the ozone feeder 30 is stopped and the addition of the ozone to the exhaust gas is also stopped.
  • next step S 222 fuel injection from the fuel injector 44 at the downstream side of the DPF 40 is executed and fuel is added to the exhaust gas flowing into the NSR catalyst 22 .
  • the fuel injection quantity of the fuel injector 44 is controlled so that the exhaust gas flowing into the NSR catalyst 22 will be a rich air-fuel ratio.
  • An output signal from the air-fuel ratio sensor 58 is fed back during the control of the fuel injection quantity.
  • the fuel that has been injected from the fuel injector 44 is burned upon reacting with the oxygen in the exhaust gas, and the resulting heat warms the exhaust gas. In addition, excess fuel is left intact in the exhaust gas and flows into the NSR catalyst 22 .
  • the NOx stored therein is reduced by the HC and CO contained in the exhaust gas, and is progressively removed from the NSR catalyst 22 .
  • Fuel addition for the regeneration of the NSR catalyst 22 is executed only for the required regenerating period calculated from the NOx storage quantity existing immediately before the regeneration.
  • the NOx storage quantity can be estimated and calculated from counts of the cumulative operating period and/or cumulative traveling distance from the previous regeneration of the NSR catalyst 22 .
  • process control proceeds to step S 224 to stop the addition of fuel from the fuel injector 44 . This completes the regeneration of the NSR catalyst 22 .
  • the exhaust gas purification device of the present embodiment can regenerate the DPF 40 and at the same time, heat the NSR catalyst 22 using the heat generated during the regeneration of the DPF 40 .
  • the creation of a lean atmosphere in the DPF 40 and that of a rich atmosphere in the NSR catalyst 22 can be achieved by supplying fuel in divided forms to the upstream and downstream sides of the DPF 40 .
  • the NSR catalyst 22 can be regenerated at the same time the DPF 40 is regenerated, and the heat generated during the regeneration of the DPF 40 can be used more effectively.
  • ozone may be supplied to a position other than the gas injection port. If ozone can be reliably added to the exhaust gas flowing into the NSR catalyst, the ozone may be supplied upstream relative to the catalytic converter, on the exhaust passage.
  • the kind of material used for the NOx-retaining substance is not limited to BaCO 3 . That is to say, an alkaline metal such as Na, K, Cs, or Rb, an alkaline earth metal such as Ba, Ca, or Sr, or a rare-earth element such as Y, Ce, La, or Pr may be used according to particular needs.
  • the kind of material used for the active site of the NSR catalyst is not limited to Pt and a noble-metal material such as Rh or Pd may be used according to particular needs.
  • the NSR catalyst can be broken down into a “catalyst” and an “NOx-retaining material”.
  • the noble metal that is the active site, and a support that supports the noble metal are equivalent to the “catalyst”, and the NOx-retaining substance and a support that supports the NOx-retaining substance are equivalent to the “NOx-retaining material”.
  • the “catalyst” and the “NOx-retaining material” do not always need to be an integrated structure and may be independent structures.
  • the “NOx storage reduction catalyst” pertaining to the present invention is not necessarily an integrated structure of the “catalyst” and the “NOx-retaining material”, and includes the “catalyst” and the “NOx-retaining material” in the form of independent structures.
  • one of the supports may be used to form the “catalyst” by supporting only a noble metal that is the active site, and the other support may be used to form the “NOx-retaining material” by supporting only the NOx-retaining substance.
  • the “catalyst” is desirably provided downstream with respect to the “NOx-retaining material” so that the “catalyst” can process the NOx released from the “NOx-retaining material”.
  • the support may be adapted to support the substances separately from each other on the upstream and downstream sides thereof, or upper-layer and lower-layer sides thereof.
  • the addition of ozone is stopped (steps S 108 and S 116 of the routine shown in FIG. 2 , or steps S 204 and S 220 of the routine shown in FIG. 4 ), but under certain conditions, the addition of ozone is anticipated to modify fuel composition. Under specific conditions, therefore, adding fuel under a coexisting state of ozone may enhance a stored-NOx reducing effect, and if this is the case, the addition of ozone may be continued.
  • the present invention is applied to a diesel engine
  • the kind of internal combustion engine to which the invention can be applied is not limited to diesel engines. If the invention is applied to the internal combustion engines, including gasoline lean-burn engines, that emit NOx-containing exhaust gases, the advantages described above can be obtained from the application of the invention.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Environmental & Geological Engineering (AREA)
  • Biomedical Technology (AREA)
  • Health & Medical Sciences (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Processes For Solid Components From Exhaust (AREA)
  • Filtering Of Dispersed Particles In Gases (AREA)
  • Exhaust Gas Treatment By Means Of Catalyst (AREA)
US12/530,842 2007-03-12 2008-03-11 Exhaust gas purification device for internal combustion engine Abandoned US20100132337A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2007-062160 2007-03-12
JP2007062160A JP5119690B2 (ja) 2007-03-12 2007-03-12 内燃機関の排気ガス浄化装置
PCT/JP2008/054379 WO2008126566A1 (ja) 2007-03-12 2008-03-11 内燃機関の排気ガス浄化装置

Publications (1)

Publication Number Publication Date
US20100132337A1 true US20100132337A1 (en) 2010-06-03

Family

ID=39842480

Family Applications (1)

Application Number Title Priority Date Filing Date
US12/530,842 Abandoned US20100132337A1 (en) 2007-03-12 2008-03-11 Exhaust gas purification device for internal combustion engine

Country Status (5)

Country Link
US (1) US20100132337A1 (zh)
EP (1) EP2157294A4 (zh)
JP (1) JP5119690B2 (zh)
CN (1) CN101636565A (zh)
WO (1) WO2008126566A1 (zh)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150315950A1 (en) * 2012-12-07 2015-11-05 Toyota Jidosha Kabushiki Kaisha Abnormality detection device for exhaust gas purification apparatus
US20160305302A1 (en) * 2015-04-17 2016-10-20 Ford Global Technologies, Llc Method and system for reducing engine exhaust emissions
US9784157B2 (en) * 2010-03-25 2017-10-10 General Electric Company System and method for exhaust treatment
CN113294226A (zh) * 2021-06-30 2021-08-24 同济大学 一种基于超声波除颗粒物的颗粒捕集器

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5401993B2 (ja) * 2009-01-08 2014-01-29 マツダ株式会社 エンジンの排気浄化装置
WO2013035663A1 (ja) * 2011-09-05 2013-03-14 日野自動車株式会社 排ガス浄化装置
JP2013122179A (ja) * 2011-12-09 2013-06-20 Toyota Motor Corp 内燃機関の排気浄化装置
JP2014047670A (ja) * 2012-08-30 2014-03-17 Denso Corp オゾン生成手段を含むエンジン用ＮＯｘ後処理装置の制御方法および制御装置
JP6551426B2 (ja) * 2017-01-13 2019-07-31 トヨタ自動車株式会社 内燃機関の排気浄化装置
WO2020083167A1 (zh) * 2018-10-22 2020-04-30 上海必修福企业管理有限公司 一种发动机尾气臭氧净化系统和方法
WO2020083096A1 (zh) * 2018-10-22 2020-04-30 上海必修福企业管理有限公司 一种发动机排放处理系统和方法
CN113366198B (zh) * 2018-10-22 2023-08-15 上海必修福企业管理有限公司 一种发动机排放处理系统和方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6012283A (en) * 1994-05-18 2000-01-11 Lockheed Martin Corp. Method and apparatus for reducing pollutants
US6212883B1 (en) * 2000-03-03 2001-04-10 Moon-Ki Cho Method and apparatus for treating exhaust gas from vehicles
US20060101810A1 (en) * 2004-11-15 2006-05-18 Angelo Theodore G System for dispensing fuel into an exhaust system of a diesel engine
US20060162297A1 (en) * 2002-09-05 2006-07-27 Patrik Hartherz Method for the post-treatment of exhaust gases and device therefor
US20070271908A1 (en) * 2006-05-25 2007-11-29 Hemingway Mark D Engine exhaust emission control system providing on-board ammonia generation
US7954313B2 (en) * 2005-10-18 2011-06-07 Toyota Jidosha Kabushiki Kaisha Exhaust cleaner for internal combustion engine

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3551805B2 (ja) * 1999-01-12 2004-08-11 トヨタ自動車株式会社 内燃機関の排気浄化装置
JP4201224B2 (ja) * 1999-01-13 2008-12-24 エムズジャパン株式会社 トイレ
JP2000297633A (ja) 1999-04-14 2000-10-24 Hitachi Ltd 内燃機関用排ガス浄化装置
JP4251764B2 (ja) 2000-09-08 2009-04-08 日産自動車株式会社 排気ガス浄化装置及びこれを用いた排気ガス浄化方法
JP2002089246A (ja) * 2000-09-20 2002-03-27 Hitachi Ltd 内燃機関の排ガス浄化方法および排ガス浄化装置
JP2002188432A (ja) 2000-12-19 2002-07-05 Isuzu Motors Ltd ディーゼルエンジンの排気浄化装置
GB0305415D0 (en) 2003-03-08 2003-04-16 Johnson Matthey Plc Exhaust system for lean burn IC engine including particulate filter and NOx absorbent
JP2005240566A (ja) * 2004-02-24 2005-09-08 Hino Motors Ltd 排気浄化装置の制御方法
JP3876905B2 (ja) * 2004-12-07 2007-02-07 いすゞ自動車株式会社 排気ガス浄化システムの脱硫制御方法及び排気ガス浄化システム
WO2006066043A1 (en) * 2004-12-15 2006-06-22 Donaldson Company, Inc. Control for an engine exhaust treatment system
FR2885953B1 (fr) * 2005-05-17 2010-10-01 Renault Sas Dispositif d'aide au fonctionnement d'un catalyseur d'oxydation pour l'epuration de gaz d'echappement d'un moteur a combustion interne et procede associe
JP4529822B2 (ja) * 2005-07-05 2010-08-25 トヨタ自動車株式会社 内燃機関の排気浄化装置

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6012283A (en) * 1994-05-18 2000-01-11 Lockheed Martin Corp. Method and apparatus for reducing pollutants
US6212883B1 (en) * 2000-03-03 2001-04-10 Moon-Ki Cho Method and apparatus for treating exhaust gas from vehicles
US20060162297A1 (en) * 2002-09-05 2006-07-27 Patrik Hartherz Method for the post-treatment of exhaust gases and device therefor
US20060101810A1 (en) * 2004-11-15 2006-05-18 Angelo Theodore G System for dispensing fuel into an exhaust system of a diesel engine
US7954313B2 (en) * 2005-10-18 2011-06-07 Toyota Jidosha Kabushiki Kaisha Exhaust cleaner for internal combustion engine
US20070271908A1 (en) * 2006-05-25 2007-11-29 Hemingway Mark D Engine exhaust emission control system providing on-board ammonia generation

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PDF file of Anderson M D et al. (WO 2006/066043 A1) *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9784157B2 (en) * 2010-03-25 2017-10-10 General Electric Company System and method for exhaust treatment
US20150315950A1 (en) * 2012-12-07 2015-11-05 Toyota Jidosha Kabushiki Kaisha Abnormality detection device for exhaust gas purification apparatus
US9879586B2 (en) * 2012-12-07 2018-01-30 Toyota Jidosha Kabushiki Kaisha Abnormality detection device for exhaust gas purification apparatus
US20160305302A1 (en) * 2015-04-17 2016-10-20 Ford Global Technologies, Llc Method and system for reducing engine exhaust emissions
US9677448B2 (en) * 2015-04-17 2017-06-13 Ford Global Technologies, Llc Method and system for reducing engine exhaust emissions
US9822689B2 (en) 2015-04-17 2017-11-21 Ford Global Technologies, Llc Method and system for reducing engine exhaust emissions
CN113294226A (zh) * 2021-06-30 2021-08-24 同济大学 一种基于超声波除颗粒物的颗粒捕集器

Also Published As

Publication number Publication date
JP2008223576A (ja) 2008-09-25
CN101636565A (zh) 2010-01-27
EP2157294A4 (en) 2011-05-04
WO2008126566A1 (ja) 2008-10-23
JP5119690B2 (ja) 2013-01-16
EP2157294A1 (en) 2010-02-24

Similar Documents

Publication Publication Date Title
US20100132337A1 (en) Exhaust gas purification device for internal combustion engine
JP5087836B2 (ja) 排気ガス浄化システムの制御方法及び排気ガス浄化システム
US8752367B2 (en) Exhaust system for lean burn IC engine including particulate filter and NOx absorbent
US8479500B2 (en) Exhaust treatment system for an internal combustion engine
JP3284274B2 (ja) ディーゼル車両用窒素酸化物の浄化制御方法
JP4686547B2 (ja) 排気ガス浄化を伴う機関駆動車両
JP2005155374A (ja) 排気浄化方法及び排気浄化システム
JP2010112345A (ja) 排気浄化装置
US9702286B2 (en) Exhaust gas purification system and exhaust gas purification method
WO2006123510A1 (ja) 排気ガス浄化方法及び排気ガス浄化システム
JP2002021544A (ja) 内燃機関の希薄排ガスから窒素酸化物およびカーボンブラック粒子を除去するための方法および排ガス浄化装置
WO2006027904A1 (ja) 誘導構造及び排気ガス浄化装置
JP2004239218A (ja) 内燃機関の排気ガス浄化システム
JP2006242020A (ja) 排気浄化装置
KR20180068808A (ko) 배기가스 정화장치 및 제어 방법
JP2007289844A (ja) 内燃機関の排気浄化装置
JP2008038634A (ja) 内燃機関の排気浄化システム
JP3885814B2 (ja) 排気ガス浄化装置の昇温方法及び排気ガス浄化システム
KR20130008881A (ko) 배기 가스 정화 장치 및 이를 제어하는 방법
JP4162239B2 (ja) 排気浄化部材の再生装置及び再生方法
JP2015045260A (ja) 内燃機関の制御装置
JP3876905B2 (ja) 排気ガス浄化システムの脱硫制御方法及び排気ガス浄化システム
JP2007127069A (ja) 排気浄化装置
JP5257332B2 (ja) 排気浄化装置
JP2010127182A (ja) 内燃機関の排気浄化装置

Legal Events

Date Code Title Description
AS Assignment

Owner name: TOYOTA JIDOSHA KABUSHIKI KAISHA,JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HIRATA, HIROHITO;IBE, MASAYA;MATSUBARA, HIROYUKI;AND OTHERS;SIGNING DATES FROM 20091007 TO 20091014;REEL/FRAME:023782/0780

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION