WO2014129449A1 - 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 PDF

Info

Publication number
WO2014129449A1
WO2014129449A1 PCT/JP2014/053737 JP2014053737W WO2014129449A1 WO 2014129449 A1 WO2014129449 A1 WO 2014129449A1 JP 2014053737 W JP2014053737 W JP 2014053737W WO 2014129449 A1 WO2014129449 A1 WO 2014129449A1
Authority
WO
WIPO (PCT)
Prior art keywords
exhaust
filter
internal combustion
combustion engine
exhaust gas
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.)
Ceased
Application number
PCT/JP2014/053737
Other languages
English (en)
French (fr)
Inventor
正 内山
充宏 阿曽
正文 野田
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.)
Isuzu Motors Ltd
Original Assignee
Isuzu Motors Ltd
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 Isuzu Motors Ltd filed Critical Isuzu Motors Ltd
Priority to CN201480016697.XA priority Critical patent/CN105143623B/zh
Priority to EP14753870.6A priority patent/EP2960453B1/en
Priority to US14/768,577 priority patent/US9664090B2/en
Publication of WO2014129449A1 publication Critical patent/WO2014129449A1/ja
Anticipated expiration legal-status Critical
Ceased 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
    • F01N3/08—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
    • F01N3/206—Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents
    • F01N3/2066—Selective catalytic reduction [SCR]
    • 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
    • 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
    • F01N13/009—Exhaust or silencing apparatus characterised by constructional features 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
    • F01N3/02—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
    • F01N3/0231—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 special exhaust apparatus upstream of the filter for producing nitrogen dioxide, e.g. for continuous filter regeneration systems [CRT]
    • 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
    • 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
    • F01N3/027—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 electric or magnetic heating means
    • F01N3/0275—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 electric or magnetic heating means using electric discharge means
    • 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
    • F01N3/031—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 having means for by-passing filters, e.g. when clogged or during cold engine start
    • 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
    • F01N3/033—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 in combination with other devices
    • F01N3/035—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 in combination with other devices with catalytic reactors
    • 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
    • F01N9/00—Electrical control of exhaust gas treating apparatus
    • F01N9/002—Electrical control of exhaust gas treating apparatus of filter regeneration
    • 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
    • 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
    • B01D53/9404—Removing only nitrogen compounds
    • B01D53/9409—Nitrogen oxides
    • B01D53/9431—Processes characterised by a specific device
    • 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
    • B01D53/944—Simultaneously removing carbon monoxide, hydrocarbons or carbon making use of oxidation catalysts
    • 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
    • B01D53/9459—Removing one or more of nitrogen oxides, carbon monoxide, or hydrocarbons by multiple successive catalytic functions; systems with more than one different function, e.g. zone coated catalysts
    • B01D53/9477—Removing one or more of nitrogen oxides, carbon monoxide, or hydrocarbons by multiple successive catalytic functions; systems with more than one different function, e.g. zone coated catalysts with catalysts positioned on separate bricks, e.g. exhaust systems
    • 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
    • B01D53/9495—Controlling the catalytic process
    • 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
    • F01N13/011—Exhaust or silencing apparatus characterised by constructional features having two or more purifying devices arranged in parallel
    • 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
    • F01N2240/16—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 electric heater, i.e. a resistance heater
    • 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
    • F01N2410/00—By-passing, at least partially, exhaust from inlet to outlet of apparatus, to atmosphere or to other device
    • 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
    • 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
    • F01N2550/04—Filtering activity of particulate filters
    • 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
    • F01N2550/06—By-pass systems
    • F01N2550/12—By-pass systems of particulate filters
    • 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
    • F01N2560/05—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being a particulate 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
    • F01N2560/12—Other sensor principles, e.g. using electro conductivity of substrate or radio frequency
    • 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
    • F01N2610/02—Adding substances to exhaust gases the substance being ammonia or urea
    • 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
    • F01N2610/14—Arrangements for the supply of substances, e.g. conduits
    • F01N2610/1453—Sprayers or atomisers; Arrangement thereof in the exhaust apparatus
    • 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
    • F01N2900/0601—Parameters used for exhaust control or diagnosing being estimated
    • 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
    • F01N2900/14—Parameters used for exhaust control or diagnosing said parameters being related to the exhaust gas
    • F01N2900/1402—Exhaust gas composition
    • 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
    • F01N2900/1606—Particle filter loading or soot amount
    • 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
    • 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
    • F01N3/0235—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 exhaust gas throttling means
    • 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
    • F01N3/2006—Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating
    • F01N3/2013—Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating using electric or magnetic heating means
    • F01N3/2026—Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating using electric or magnetic heating means directly electrifying the catalyst substrate, i.e. heating the electrically conductive catalyst substrate by joule effect
    • 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
    • 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 purification device for an internal combustion engine.
  • a filter that collects particulate matter (Particulate Matter, hereinafter referred to as PM) in exhaust gas discharged from a diesel engine for example, a diesel particulate filter (Diesel Particulate Filter, hereinafter referred to as DPF) is known. Yes.
  • NOx catalyst for purifying nitrogen compounds (hereinafter referred to as NOx) in exhaust gas ammonia (NH 3 ) produced by hydrolysis from urea water by exhaust heat is used to selectively reduce NOx in exhaust gas.
  • a selective reduction catalyst hereinafter referred to as SCR
  • SCR selective reduction catalyst
  • NOx carbon monoxide: NO, carbon dioxide: NO 2
  • NH 3 ammonia
  • the present invention has been made in view of such a point, and the object thereof is to control the NOx purification rate by controlling the ratio of NO and NO 2 in the exhaust gas flowing into the SCR with high accuracy. Is to improve.
  • an exhaust gas purification apparatus for an internal combustion engine includes a filter provided in an exhaust passage of the internal combustion engine for collecting particulate matter in the exhaust, and an exhaust gas downstream of the filter.
  • a urea water injection means provided in the passage for injecting urea water into the exhaust gas; and provided in an exhaust passage downstream of the urea water injection means and using ammonia generated from the urea water.
  • the capacitance detection means may have a pair of electrodes respectively inserted into a pair of cells facing each other with at least one or more cells in the filter interposed therebetween.
  • a bypass passage that branches from the exhaust passage upstream of the filter and bypasses the filter; and a second passage that is provided in the bypass passage and collects particulate matter in the exhaust gas flowing through the bypass passage.
  • the pair of electrodes may be inserted into a pair of cells facing each other with at least one or more cells in the second filter interposed therebetween.
  • the pair of electrodes may function as a heater.
  • the NOx purification rate can be effectively improved by controlling the ratio of NO and NO 2 in the exhaust gas flowing into the SCR with high accuracy.
  • FIG. 1 is a schematic overall configuration diagram showing an exhaust emission control device for an internal combustion engine according to an embodiment of the present invention.
  • the exhaust purification system of an internal combustion engine according to an embodiment of the present invention it is a diagram illustrating an example of a map for calculating the NO 2 consumed from the PM accumulation amount. It is a typical whole block diagram which shows the exhaust gas purification apparatus of the internal combustion engine which concerns on other embodiment of this invention.
  • a diesel engine (hereinafter simply referred to as an engine) 10 is provided with an intake manifold 10a and an exhaust manifold 10b.
  • An intake passage 11 for introducing fresh air is connected to the intake manifold 10a, and an exhaust passage 12 for releasing exhaust gas to the atmosphere is connected to the exhaust manifold 10b.
  • the exhaust passage 12 is provided with a pre-stage post-treatment device 14 and a post-stage post-treatment device 20 in order from the exhaust upstream side.
  • the pre-stage post-treatment device 14 is configured by arranging an oxidation catalyst (Diesel Oxidation Catalyst: hereinafter referred to as DOC) 15 and a DPF 16 in order from the upstream side in a case 14a. Further, an exhaust pipe injection device 13 is provided upstream of the DOC 15, a DPF inlet temperature sensor 18 is provided upstream of the DPF 16, and a DPF outlet temperature sensor 19 is provided downstream of the DPF 16.
  • DOC Diesel Oxidation Catalyst
  • the exhaust pipe injection device 13 injects unburned fuel (mainly HC) into the exhaust passage 12 in accordance with an instruction signal output from an electronic control unit (hereinafter, ECU) 40.
  • ECU electronice control unit
  • this in-pipe injection device 13 may be omitted.
  • the DOC 15 is formed, for example, by supporting a catalyst component on the surface of a ceramic carrier such as a cordierite honeycomb structure.
  • a catalyst component such as a cordierite honeycomb structure.
  • unburned fuel mainly HC
  • the DOC 15 oxidizes this and raises the temperature of the exhaust gas.
  • DOC15 the exhaust by oxidizing NO in the gas to produce a NO 2, thereby increasing the ratio of NO 2 to NO in the exhaust gas.
  • the DPF 16 is formed, for example, by arranging a large number of cells partitioned by porous partition walls along the exhaust gas flow direction, and alternately plugging the upstream side and the downstream side of these cells. .
  • the DPF 16 collects PM in the exhaust gas in the pores and surfaces of the partition walls, and performs so-called forced regeneration that burns and removes the PM when the PM accumulation amount reaches a predetermined amount.
  • the forced regeneration is performed by supplying unburned fuel (mainly HC) to the DOC 15 by the exhaust pipe injection device 13 or post injection, and raising the DPF 16 to the PM combustion temperature (for example, about 600 ° C.).
  • the DPF 16 of the present embodiment is provided with a pair of electrodes 17a and 17b that are inserted into a pair of cells facing each other with at least one or more cells interposed therebetween to form a capacitor.
  • the pair of electrodes 17a and 17b are electrically connected to the ECU 40.
  • the DPF inlet temperature sensor 18 detects the temperature of exhaust gas flowing into the DPF 16 (hereinafter referred to as inlet temperature T IN ).
  • the DPF outlet temperature sensor 19 detects the temperature of exhaust gas flowing out from the DPF 16 (hereinafter referred to as outlet temperature T OUT ).
  • the inlet temperature T IN and the outlet temperature T OUT are output to the electrically connected ECU 40.
  • the post-stage post-processing device 20 includes a urea water injection device 21 and an SCR 22 disposed in the case 20a in order from the upstream side.
  • the urea water injection device 21 injects urea water in a urea water tank (not shown) into the exhaust passage 12 between the pre-stage post-treatment device 14 and the post-stage post-treatment device 20 in response to an instruction signal output from the ECU 40. To do.
  • the injected urea water is hydrolyzed by exhaust heat to be generated into ammonia (NH 3 ), and is supplied to the downstream SCR 22 as a reducing agent.
  • the SCR 22 is formed, for example, by supporting copper zeolite or iron zeolite on the surface of a ceramic carrier such as a honeycomb structure.
  • the SCR 22 adsorbs ammonia (NH 3 ) supplied as a reducing agent and reduces and purifies NOx from the exhaust gas passing through the adsorbed ammonia (NH 3 ).
  • the ECU 40 performs various controls of the engine 10, the exhaust pipe injection device 13, the urea water injection device 21, and the like, and includes a known CPU, ROM, RAM, input port, output port, and the like.
  • the ECU 40 includes a capacitance calculation unit 41, a PM accumulation amount calculation unit 42, a NO 2 consumption amount estimation unit 43, a NOx inflow rate calculation unit 44, and a NOx inflow rate adjustment unit 45, with some functions. Have as an element.
  • Each of these functional elements will be described as being included in the ECU 40 which is an integral hardware, but any one of them can be provided in separate hardware.
  • the capacitance calculation unit 41 and the electrodes 17a and 17b constitute the capacitance detection means of the present invention.
  • the electrostatic capacity calculator 41 calculates the electrostatic capacity C between the electrodes 17a and 17b based on signals input from the pair of electrodes 17a and 17b.
  • the electrostatic capacity C is calculated by the following formula 1, which is the dielectric constant ⁇ of the medium between the electrodes 17a and 17b, the area S of the electrodes 17a and 17b, and the distance d between the electrodes 17a and 17b.
  • the PM accumulation amount calculation unit 42 calculates the average value T AVE of the inlet temperature T IN detected by the DPF inlet temperature sensor 18 and the outlet temperature T OUT detected by the DPF outlet temperature sensor 19 and the capacitance calculation unit 41. Based on the capacitance C to be calculated, the PM accumulation amount collected in the DPF 16 is calculated. For calculating the PM deposition amount, an approximate expression or a map obtained in advance through experiments or the like can be used.
  • NO 2 consumption estimation unit 43 based on the PM accumulation amount calculated by the PM accumulation amount calculation unit 42 estimates the NO 2 consumption consumed by PM deposited in the DPF 16. More specifically, the ECU 40 stores a consumption map (see FIG. 2) that prescribes the relationship between the PM accumulation amount and the NO 2 consumption amount obtained in advance by experiments or the like. NO 2 consumption estimating unit 43, by reading a value corresponding to the PM accumulation amount from the consumption amount map, estimates the NO 2 consumption.
  • the NOx inflow ratio calculation unit 44 calculates the ratio between NO and NO 2 in the exhaust gas that passes through the DPF 16 and flows into the SCR 22. A more detailed calculation method will be described below. First, the NOx inflow ratio calculation unit 44 calculates the amount of NO and the amount of NO 2 in the exhaust gas discharged from the engine 10 based on the operating state of the engine 10. Further, the amount of NO 2 produced from NO by oxidation in the DOC 15 is calculated. Then, NOx inflow ratio calculation unit 44, these calculated amount of NO, NO 2 amount, the NO 2 generation amount, calculates the NO 2 amount flowing to the DPF 16, by further subtracting the NO 2 consumption by PM, The ratio of NO to NO 2 in the exhaust gas flowing into the SCR 22 is calculated.
  • the NOx inflow ratio adjusting unit 45 controls the combustion state of the engine 10 so that the ratio of NO and NO 2 calculated by the NOx inflow ratio calculating unit 44 approaches 1: 1. Thereby, the ratio of NO to NO 2 in the exhaust gas flowing into the SCR 22 is always maintained at an ideal 1: 1, and the NOx purification rate by the SCR 22 is improved.
  • the control for bringing the ratio of NO and NO 2 close to 1: 1 can be performed by adjusting parameters such as the fuel injection timing (ignition timing) of the engine 10, the exhaust gas recirculation amount, and the air-fuel ratio, for example. .
  • the exhaust gas purification apparatus for an internal combustion engine of the present embodiment calculates the PM accumulation amount from the capacitance C between the electrodes 17a and 17b that is not affected by the exhaust gas flow rate, and also consumes NO 2 by PM. In consideration of the above, the ratio of NO and NO 2 flowing into the SCR 22 is maintained at 1: 1.
  • the PM accumulation amount of the DPF 16 can be detected with high accuracy, and the ratio of NO and NO 2 flowing into the SCR 22 is always maintained at an ideal 1: 1. This makes it possible to effectively improve the NOx purification rate. Further, the reaction of NO, NO 2 and ammonia (NH 3 ) in the SCR 22 is promoted, so that excess ammonia can be effectively reduced.
  • a bypass passage 12a for bypassing the DPF 16 may be connected to the exhaust passage 12, and the bypass passage 12a may be provided with a measurement DPF 16a (second filter) having a small capacity.
  • the pair of electrodes 17a and 17b are inserted into a pair of cells facing each other with at least one or more cells in the measurement DPF 16a interposed therebetween, and an orifice 12b (throttling) for adjusting the flow rate of exhaust gas is provided in the bypass passage 12a.
  • a voltage may be applied to the pair of electrodes 17a and 17b so as to function as a heater.
  • the engine 10 is not limited to a diesel engine, and can be widely applied to other internal combustion engines such as a gasoline engine.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Processes For Solid Components From Exhaust (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Exhaust Gas Treatment By Means Of Catalyst (AREA)

Abstract

　内燃機関の排気浄化装置に関し、ＮＯｘの浄化率を効果的に向上させる。　排気中のＰＭを捕集するＤＰＦ１６と、排気中に尿素水を噴射する尿素水噴射装置２１と、排気中のＮＯｘを還元浄化するＳＣＲ２２と、ＤＰＦ１６の静電容量を検出する静電容量検出ユニット１７ａ，１７ｂ，４１と、静電容量に基づいてＰＭ堆積量を算出するＰＭ堆積量算出部４２と、ＰＭ堆積量に基づいてＮＯ2の消費量を算出するＮＯ2消費量推定部４３と、推定される消費量に基づいて、ＳＣＲ２２に流入するＮＯとＮＯ2の比率が１：１に近づくように、エンジン１０を制御する制御ユニット４４，４５とを備えた。

Description

内燃機関の排気浄化装置
　本発明は、内燃機関の排気浄化装置に関する。
　ディーゼルエンジンから排出される排気ガス中の粒子状物質（Particulate Matter、以下、ＰＭ）を捕集するフィルタとして、例えば、ディーゼル・パティキュレイト・フィルタ（Diesel Particulate Filter、以下、ＤＰＦ）が知られている。
　また、排気ガス中の窒素化合物（以下、ＮＯｘ）を浄化するＮＯｘ触媒として、尿素水から排気熱により加水分解されて生成されるアンモニア（ＮＨ3）を用いて排気ガス中のＮＯｘを選択的に還元浄化する選択的還元触媒（Selective Catalytic Reduction：以下、ＳＣＲという）も知られている。ＳＣＲにおいては、特に排気温度が低い時には排気ガス中のＮＯｘ（一酸化炭素：ＮＯ，二酸化炭素：ＮＯ2）は、以下の反応式でアンモニア（ＮＨ3）と反応して浄化される。　
２ＮＨ3＋ＮＯ＋ＮＯ2→２Ｎ2＋３Ｈ2Ｏ・・・式（１）
　そのため、ＳＣＲによるＮＯｘの浄化率を向上するためには、ＮＯとＮＯ2との比率を１：１に維持することが好ましい。
特開２０１３－２２８３号公報 特開２００９－２４３３１６号公報
　ところで、排気ガス中のＮＯ2は、ＤＰＦに捕集されたＰＭと反応して消費される傾向がある。そのため、下流側のＳＣＲに流入する排気ガス中のＮＯとＮＯ2との比率を１：１に維持するためには、上流側のＤＰＦに捕集されたＰＭ堆積量を高精度に測定することによりＳＣＲの浄化率を向上することができる。
　本発明は、このような点に鑑みてなされたもので、その目的は、ＳＣＲに流入する排気ガス中のＮＯとＮＯ2との比率を高精度に制御することで、ＮＯｘの浄化率を効果的に向上させることにある。
　上述の目的を達成するため、本発明の内燃機関の排気浄化装置は、内燃機関の排気通路に設けられて、排気中の粒子状物質を捕集するフィルタと、前記フィルタよりも下流側の排気通路に設けられて、排気中に尿素水を噴射する尿素水噴射手段と、前記尿素水噴射手段よりも下流側の排気通路に設けられて、尿素水から生成されるアンモニアを用いて排気中の窒素化合物を還元浄化する選択的還元触媒と、前記フィルタの静電容量を検出する静電容量検出手段と、検出される前記静電容量に基づいて、前記フィルタに捕集された粒子状物質の堆積量を推定する堆積量推定手段と、推定される前記堆積量に基づいて、前記フィルタに堆積した粒子状物質による二酸化窒素の消費量を算出する消費量算出手段と、算出される前記消費量に基づいて、前記選択的還元触媒に流入する排気中の一酸化炭素と二酸化窒素との比率が１：１に近づくように、前記内燃機関の燃焼状態を制御する制御手段と、を備えることを特徴とする。
　また、前記静電容量検出手段は、前記フィルタ内の少なくとも一個以上のセルを挟んで対向する一対のセルにそれぞれ挿入される一対の電極を有するものであってもよい。
　また、前記フィルタよりも上流側の排気通路から分岐して、当該フィルタを迂回するバイパス通路と、前記バイパス通路に設けられて、当該バイパス通路を流れる排気中の粒子状物質を捕集する第２のフィルタと、をさらに備え、前記一対の電極は、前記第２のフィルタ内の少なくとも一個以上のセルを挟んで対向する一対のセルにそれぞれ挿入されるものであってもよい。
　また、前記第２のフィルタの強制再生を実行する際は、前記一対の電極をヒータとして機能させてもよい。
　本発明の内燃機関の排気浄化装置によれば、ＳＣＲに流入する排気ガス中のＮＯとＮＯ2との比率を高精度に制御することで、ＮＯｘの浄化率を効果的に向上させることができる。
本発明の一実施形態に係る内燃機関の排気浄化装置を示す模式的な全体構成図である。 本発明の一実施形態に係る内燃機関の排気浄化装置において、ＰＭ堆積量からＮＯ2消費量を算出するマップの一例を示す図である。 本発明の他の実施形態に係る内燃機関の排気浄化装置を示す模式的な全体構成図である。
　以下、図１，２に基づいて、本発明の一実施形態に係る内燃機関の排気浄化装置を説明する。同一の部品には同一の符号を付してあり、それらの名称および機能も同じである。したがって、それらについての詳細な説明は繰返さない。
　図１に示すように、ディーゼルエンジン（以下、単にエンジン）１０には、吸気マニホールド１０ａと排気マニホールド１０ｂとが設けられている。吸気マニホールド１０ａには新気を導入する吸気通路１１が接続され、排気マニホールド１０ｂには排気ガスを大気に放出する排気通路１２が接続されている。さらに、排気通路１２には、排気上流側から順に、前段後処理装置１４、後段後処理装置２０が設けられている。
　前段後処理装置１４は、ケース１４ａ内に上流側から順に酸化触媒（Diesel Oxidation Catalyst：以下、ＤＯＣという）１５と、ＤＰＦ１６とを配置して構成されている。また、ＤＯＣ１５の上流側には排気管内噴射装置１３、ＤＰＦ１６の上流側にはＤＰＦ入口温度センサ１８、ＤＰＦ１６の下流側にはＤＰＦ出口温度センサ１９がそれぞれ設けられている。
　排気管内噴射装置１３は、電子制御ユニット（以下、ＥＣＵ）４０から出力される指示信号に応じて、排気通路１２内に未燃燃料（主にＨＣ）を噴射する。なお、エンジン１０の多段噴射によるポスト噴射を用いる場合は、この排気管内噴射装置１３を省略してもよい。
　ＤＯＣ１５は、例えば、コーディエライトハニカム構造体等のセラミック製担体表面に触媒成分を担持して形成されている。ＤＯＣ１５は、排気管内噴射装置１３又はポスト噴射によって未燃燃料（主にＨＣ）が供給されると、これを酸化して排気ガスの温度を上昇させる。また、ＤＯＣ１５は、排気ガス中のＮＯを酸化してＮＯ2を生成することで、排気ガス中のＮＯに対するＮＯ2の比率を増加させる。
　ＤＰＦ１６は、例えば、多孔質性の隔壁で区画された多数のセルを排気ガスの流れ方向に沿って配置し、これらセルの上流側と下流側とを交互に目封止して形成されている。ＤＰＦ１６は、排気ガス中のＰＭを隔壁の細孔や表面に捕集すると共に、ＰＭの堆積量が所定量に達すると、これを燃焼除去するいわゆる強制再生が実行される。強制再生は、排気管内噴射装置１３又はポスト噴射によりＤＯＣ１５に未燃燃料（主にＨＣ）を供給し、ＤＰＦ１６をＰＭ燃焼温度（例えば、約６００℃）まで昇温することで行われる。
　また、本実施形態のＤＰＦ１６には、少なくとも一個以上のセルを挟んで対向する一対のセルにそれぞれ挿入されてコンデンサを形成する一対の電極１７ａ，１７ｂが設けられている。これら一対の電極１７ａ，１７ｂは、ＥＣＵ４０と電気的に接続されている。
　ＤＰＦ入口温度センサ１８は、ＤＰＦ１６に流入する排気ガスの温度（以下、入口温度ＴIN）を検出する。ＤＰＦ出口温度センサ１９は、ＤＰＦ１６から流出する排気ガスの温度（以下、出口温度ＴOUT）を検出する。これら入口温度ＴIN及び出口温度ＴOUTは、電気的に接続されたＥＣＵ４０に出力される。
　後段後処理装置２０は、上流側から順に尿素水噴射装置２１と、ケース２０ａ内に配置されたＳＣＲ２２とを備え構成されている。
　尿素水噴射装置２１は、ＥＣＵ４０から出力される指示信号に応じて、前段後処理装置１４と後段後処理装置２０との間の排気通路１２内に、図示しない尿素水タンク内の尿素水を噴射する。噴射された尿素水は排気熱により加水分解されてアンモニア（ＮＨ3）に生成され、下流側のＳＣＲ２２に還元剤として供給される。
　ＳＣＲ２２は、例えば、ハニカム構造体等のセラミック製担体表面に銅ゼオライト又は鉄ゼオライトを担持して形成されている。ＳＣＲ２２は、還元剤として供給されるアンモニア（ＮＨ3）を吸着すると共に、吸着したアンモニア（ＮＨ3）で通過する排気ガス中からＮＯｘを還元浄化する。
　ＥＣＵ４０は、エンジン１０や排気管内噴射装置１３、尿素水噴射装置２１等の各種制御を行うもので、公知のＣＰＵやＲＯＭ、ＲＡＭ、入力ポート、出力ポート等を備え構成されている。また、ＥＣＵ４０は、静電容量演算部４１と、ＰＭ堆積量算出部４２と、ＮＯ2消費量推定部４３と、ＮＯｘ流入比率算出部４４と、ＮＯｘ流入比率調整部４５とを一部の機能要素として有する。これら各機能要素は、一体のハードウェアであるＥＣＵ４０に含まれるものとして説明するが、これらのいずれか一部を別体のハードウェアに設けることもできる。なお、本実施形態において、静電容量演算部４１及び電極１７ａ，１７ｂは、本発明の静電容量検出手段を構成する。
　静電容量演算部４１は、一対の電極１７ａ，１７ｂから入力される信号に基づいて、これら電極１７ａ，１７ｂ間の静電容量Ｃを演算する。静電容量Ｃは、電極１７ａ，１７ｂ間の媒体の誘電率ε、電極１７ａ，１７ｂの面積Ｓ、電極１７ａ，１７ｂ間の距離ｄとする以下の数式１で演算される。
Figure JPOXMLDOC01-appb-M000001
　ＰＭ堆積量算出部４２は、ＤＰＦ入口温度センサ１８で検出される入口温度ＴIN及びＤＰＦ出口温度センサ１９で検出される出口温度ＴOUTの平均値ＴAVEと、静電容量演算部４１で演算される静電容量Ｃとに基づいて、ＤＰＦ１６に捕集されたＰＭ堆積量を算出する。ＰＭ堆積量の算出には、予め実験等により求めた近似式やマップ等を用いることができる。
　ＮＯ2消費量推定部４３は、ＰＭ堆積量算出部４２で算出されるＰＭ堆積量に基づいて、ＤＰＦ１６に堆積したＰＭによって消費されるＮＯ2消費量を推定する。より詳しくは、ＥＣＵ４０には、予め実験等により求めたＰＭ堆積量とＮＯ2消費量との関係を規定する消費量マップ（図２参照）が記憶されている。ＮＯ2消費量推定部４３は、この消費量マップからＰＭ堆積量に対応する値を読み取ることで、ＮＯ2消費量を推定する。
　ＮＯｘ流入比率算出部４４は、ＤＰＦ１６を通過してＳＣＲ２２に流入する排気ガス中のＮＯとＮＯ2との比率を算出する。より詳しい算出方法を以下に説明する。まず、ＮＯｘ流入比率算出部４４は、エンジン１０の運転状態に基づいて、エンジン１０から排出される排気ガス中のＮＯ量とＮＯ2量とを算出する。また、ＤＯＣ１５で酸化によりＮＯから生成されるＮＯ2生成量を算出する。そして、ＮＯｘ流入比率算出部４４は、これら算出したＮＯ量、ＮＯ2量、ＮＯ2生成量から、ＤＰＦ１６に流入するＮＯ2量を算出し、さらにＰＭによるＮＯ2消費量を減算することで、ＳＣＲ２２に流入する排気ガス中のＮＯとＮＯ2との比率を算出するように構成されている。
　ＮＯｘ流入比率調整部４５は、ＮＯｘ流入比率算出部４４により算出されたＮＯとＮＯ2との比が１：１に近づくように、エンジン１０の燃焼状態を制御する。これにより、ＳＣＲ２２に流入する排気ガス中のＮＯとＮＯ2との比は常時理想的な１：１に維持されて、ＳＣＲ２２によるＮＯｘの浄化率が向上される。なお、ＮＯとＮＯ2との比を１：１に近づける制御は、例えば、エンジン１０の燃料噴射時期（着火時期）、排気再循環量、空燃比等のパラメータを調整することで行うことができる。
　次に、本実施形態に係る内燃機関の排気浄化装置による作用効果を説明する。
　従来、上流側にＤＰＦ、下流側にＳＣＲを配置した排気浄化システムでは、ＤＰＦに堆積したＰＭによってＮＯ2が消費されるため、ＳＣＲに流入するＮＯとＮＯ2との比率を１：１に維持することが困難であった。そのため、ＳＣＲにおいては、ＮＯ，ＮＯ2とアンモニア（ＮＨ3）との反応が低下して、ＮＯｘの浄化率を悪化させる課題がある。また、一般的にＤＰＦのＰＭ堆積量は、差圧センサで検出されるＤＰＦ差圧に基づいて推定されるが、排気ガス流量は運転状態に伴い変化するため、ＤＰＦ差圧ではＰＭ堆積量を正確に把握できない課題もある。
　これに対し、本実施形態の内燃機関の排気浄化装置は、排気ガス流量の影響を受けない電極１７ａ，１７ｂ間の静電容量ＣからＰＭ堆積量を算出すると共に、ＰＭによるＮＯ2の消費量を考慮に入れて、ＳＣＲ２２に流入するＮＯとＮＯ2との比率を１：１に維持するように構成されている。
　したがって、本実施形態の内燃機関の排気浄化装置によれば、ＤＰＦ１６のＰＭ堆積量を高精度に検出できると共に、ＳＣＲ２２に流入するＮＯとＮＯ2との比率を常時理想的な１：１に維持することが可能となり、ＮＯｘの浄化率を効果的に向上することができる。また、ＳＣＲ２２のＮＯ，ＮＯ2とアンモニア（ＮＨ3）との反応が促進されることで、余剰のアンモニアを効果的に低減することが可能になる。
　なお、本発明は、上述の実施形態に限定されるものではなく、本発明の趣旨を逸脱しない範囲で、適宜変形して実施することが可能である。
　例えば、図３に示すように、排気通路１２にＤＰＦ１６を迂回させるバイパス通路１２ａを接続し、このバイパス通路１２ａに容量の小さい計測用ＤＰＦ１６ａ（第２のフィルタ）を備えて構成してもよい。この場合、一対の電極１７ａ，１７ｂを計測用ＤＰＦ１６ａ内の少なくとも一個以上のセルを挟んで対向する一対のセルにそれぞれ挿入すると共に、バイパス通路１２ａには排気ガスの流量を調整するオリフィス１２ｂ（絞り）を設けることが好ましい。また、計測用ＤＰＦ１６ａの強制再生を実行する場合は、一対の電極１７ａ，１７ｂに電圧を印加してヒータとして機能させてもよい。
　また、エンジン１０はディーゼルエンジンに限定されず、ガソリンエンジン等の他の内燃機関にも広く適用することが可能である。
　１０　エンジン
　１２　排気通路
　１３　排気管内噴射装置
　１４　前段後処理装置
　１６　ＤＰＦ（フィルタ）
　１７ａ，１７ｂ　電極（静電容量検出手段）
　２０　後段後処理装置
　２１　尿素水噴射装置（尿素水噴射手段）
　２２　ＳＣＲ（選択的還元触媒）
　４０　ＥＣＵ
　４１　静電容量演算部（静電容量検出手段）
　４２　ＰＭ堆積量算出部（堆積量算出手段）
　４３　ＮＯ2消費量推定部（消費量算出手段）
　４４　ＮＯｘ流入比率算出部（制御手段）
　４５　ＮＯｘ流入比率調整部（制御手段）

Claims (4)

  1. 　内燃機関の排気通路に設けられて、排気中の粒子状物質を捕集するフィルタと、
    　前記フィルタよりも下流側の排気通路に設けられて、排気中に尿素水を噴射する尿素水噴射手段と、
    　前記尿素水噴射手段よりも下流側の排気通路に設けられて、尿素水から生成されるアンモニアを用いて排気中の窒素化合物を還元浄化する選択的還元触媒と、
    　前記フィルタの静電容量を検出する静電容量検出手段と、
    　検出される前記静電容量に基づいて、前記フィルタに捕集された粒子状物質の堆積量を算出する堆積量算出手段と、
    　算出される前記堆積量に基づいて、前記フィルタに堆積した粒子状物質による二酸化窒素の消費量を推定する消費量推定手段と、
    　推定される前記消費量に基づいて、前記選択的還元触媒に流入する排気中の一酸化炭素と二酸化窒素との比率が１：１に近づくように、前記内燃機関の燃焼状態を制御する制御手段と、を備える
    　ことを特徴とする内燃機関の排気浄化装置。
  2. 　前記静電容量検出手段は、
    　前記フィルタ内の少なくとも一個以上のセルを挟んで対向する一対のセルにそれぞれ挿入される一対の電極を有する
    　請求項１に記載の内燃機関の排気浄化装置。
  3. 　前記フィルタよりも上流側の排気通路から分岐して、当該フィルタを迂回するバイパス通路と、
    　前記バイパス通路に設けられて、当該バイパス通路を流れる排気中の粒子状物質を捕集する第２のフィルタと、をさらに備え、
    　前記一対の電極は、前記第２のフィルタ内の少なくとも一個以上のセルを挟んで対向する一対のセルにそれぞれ挿入される
    　請求項２に記載の内燃機関の排気浄化装置。
  4. 　前記第２のフィルタの強制再生を実行する際は、前記一対の電極をヒータとして機能させる
    　請求項３に記載の内燃機関の排気浄化装置。
PCT/JP2014/053737 2013-02-22 2014-02-18 内燃機関の排気浄化装置 Ceased WO2014129449A1 (ja)

Priority Applications (3)

Application Number Priority Date Filing Date Title
CN201480016697.XA CN105143623B (zh) 2013-02-22 2014-02-18 内燃机的排气净化装置
EP14753870.6A EP2960453B1 (en) 2013-02-22 2014-02-18 Exhaust purification device for internal combustion engine
US14/768,577 US9664090B2 (en) 2013-02-22 2014-02-18 Exhaust purification device for internal combustion engine

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2013-033286 2013-02-22
JP2013033286A JP6136351B2 (ja) 2013-02-22 2013-02-22 内燃機関の排気浄化装置

Publications (1)

Publication Number Publication Date
WO2014129449A1 true WO2014129449A1 (ja) 2014-08-28

Family

ID=51391239

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2014/053737 Ceased WO2014129449A1 (ja) 2013-02-22 2014-02-18 内燃機関の排気浄化装置

Country Status (5)

Country Link
US (1) US9664090B2 (ja)
EP (1) EP2960453B1 (ja)
JP (1) JP6136351B2 (ja)
CN (1) CN105143623B (ja)
WO (1) WO2014129449A1 (ja)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2590186A (en) * 2014-12-31 2021-06-23 Cummins Emission Solutions Inc Single module integrated aftertreatment module

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101816430B1 (ko) * 2016-08-17 2018-02-21 현대자동차주식회사 배기가스정화시스템의 제어방법
DE102016219387B4 (de) 2016-10-06 2019-01-24 Audi Ag Verfahren und Vorrichtung zur Kalibrierung eines Abgassensors
CN106837495B (zh) * 2016-12-26 2019-07-30 潍柴动力股份有限公司 基于模型的doc后no2％预估方法
US10641153B1 (en) * 2018-11-26 2020-05-05 Tenneco Automotive Operating Company Inc. Exhaust after-treatment system having an oxidation component bypass for low temperature SCR
DE102019203306A1 (de) * 2019-03-12 2020-09-17 Vitesco Technologies GmbH Abgasnachbehandlungsvorrichtung und Verfahren zum Betrieb der Vorrichtung
CN109973177A (zh) * 2019-03-29 2019-07-05 河南科技大学 一种柴油机后处理装置
CN110925066B (zh) * 2020-02-17 2020-05-22 潍柴动力股份有限公司 后处理控制方法及发动机

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007255345A (ja) * 2006-03-24 2007-10-04 Isuzu Motors Ltd 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
WO2008117853A1 (ja) * 2007-03-27 2008-10-02 Ngk Insulators, Ltd. 微粒子センサ
JP2008231950A (ja) * 2007-03-16 2008-10-02 Toyota Motor Corp 内燃機関の排気浄化装置
JP2009097410A (ja) * 2007-10-16 2009-05-07 Toyota Motor Corp パティキュレートフィルタにおけるｐｍ捕集量推定装置およびフィルタ再生システム
JP2009243316A (ja) 2008-03-31 2009-10-22 Sumitomo Electric Ind Ltd 排気ガス浄化装置及びその排気ガス浄化方法
JP2012012983A (ja) * 2010-06-30 2012-01-19 Isuzu Motors Ltd ディーゼルパティキュレートフィルタシステム
JP2012052510A (ja) * 2010-09-03 2012-03-15 Honda Motor Co Ltd 内燃機関の排気浄化システム
JP2013002283A (ja) 2011-06-10 2013-01-07 Hitachi Constr Mach Co Ltd 排気浄化装置

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0621546B2 (ja) * 1988-03-11 1994-03-23 工業技術院長 排気中微粒子処理方法及び装置
JP4260345B2 (ja) * 2000-07-03 2009-04-30 日産ディーゼル工業株式会社 ディーゼルエンジンの排気浄化装置
KR100907363B1 (ko) * 2008-03-03 2009-07-10 현대자동차주식회사 Ｕｒｅａ-ｓｃｒ 시스템 제어방법
DE102008049098A1 (de) * 2008-09-26 2009-06-25 Daimler Ag Verfahren zum Betreiben einer Abgasreinigungsanlage mit einem SCR-Katalysator und einem vorgeschalteten oxidationskatalytisch wirksamen Abgasreinigungsbauteil
EP2379851B1 (de) * 2009-01-22 2015-12-16 MAN Truck & Bus AG Vorrichtung und verfahren zur regeneration eines im abgastrakt einer brennkraftmaschine angeordneten partikelfilters
WO2010113295A1 (ja) * 2009-03-31 2010-10-07 イビデン株式会社 微粒子濃度測定装置
JP5625265B2 (ja) * 2009-06-12 2014-11-19 いすゞ自動車株式会社 Ｐｍセンサ
JP5565005B2 (ja) * 2010-03-10 2014-08-06 いすゞ自動車株式会社 Ｄｐｆ故障検出方法及びｄｐｆ故障検出装置
DE102011003019A1 (de) * 2011-01-24 2012-07-26 Ford Global Technologies, Llc Partikelfilter und Verfahren zur Reinigung eines Abgasstroms
JP5351186B2 (ja) * 2011-01-25 2013-11-27 本田技研工業株式会社 内燃機関の排気浄化システム
WO2012124173A1 (ja) * 2011-03-17 2012-09-20 トヨタ自動車株式会社 内燃機関の排気浄化装置
US9162183B2 (en) * 2012-03-06 2015-10-20 Cummins Inc. System and method to manage SCR catalyst NO2/NOX ratio
US9151205B2 (en) * 2013-02-15 2015-10-06 Indiana University Research & Technology Corporation Real-time soot measurement in a diesel particulate filter

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007255345A (ja) * 2006-03-24 2007-10-04 Isuzu Motors Ltd 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
JP2008231950A (ja) * 2007-03-16 2008-10-02 Toyota Motor Corp 内燃機関の排気浄化装置
WO2008117853A1 (ja) * 2007-03-27 2008-10-02 Ngk Insulators, Ltd. 微粒子センサ
JP2009097410A (ja) * 2007-10-16 2009-05-07 Toyota Motor Corp パティキュレートフィルタにおけるｐｍ捕集量推定装置およびフィルタ再生システム
JP2009243316A (ja) 2008-03-31 2009-10-22 Sumitomo Electric Ind Ltd 排気ガス浄化装置及びその排気ガス浄化方法
JP2012012983A (ja) * 2010-06-30 2012-01-19 Isuzu Motors Ltd ディーゼルパティキュレートフィルタシステム
JP2012052510A (ja) * 2010-09-03 2012-03-15 Honda Motor Co Ltd 内燃機関の排気浄化システム
JP2013002283A (ja) 2011-06-10 2013-01-07 Hitachi Constr Mach Co Ltd 排気浄化装置

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP2960453A4

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2590186A (en) * 2014-12-31 2021-06-23 Cummins Emission Solutions Inc Single module integrated aftertreatment module
GB2590186B (en) * 2014-12-31 2021-09-15 Cummins Emission Solutions Inc Single module integrated aftertreatment module
GB2593295A (en) * 2014-12-31 2021-09-22 Cummins Emission Solutions Inc Single module integrated aftertreatment module
US11141696B2 (en) 2014-12-31 2021-10-12 Cummins Emission Solutions, Inc. Single module integrated aftertreatment module
GB2593295B (en) * 2014-12-31 2021-12-29 Cummins Emission Solutions Inc Single module integrated aftertreatment module

Also Published As

Publication number Publication date
US9664090B2 (en) 2017-05-30
JP6136351B2 (ja) 2017-05-31
EP2960453A1 (en) 2015-12-30
US20160053654A1 (en) 2016-02-25
EP2960453B1 (en) 2017-11-15
CN105143623A (zh) 2015-12-09
EP2960453A4 (en) 2016-09-21
CN105143623B (zh) 2017-12-19
JP2014163253A (ja) 2014-09-08

Similar Documents

Publication Publication Date Title
JP6136351B2 (ja) 内燃機関の排気浄化装置
CN105026717B (zh) 内燃机的排气净化装置
WO2015041289A1 (ja) 診断装置
JP2013142363A (ja) ディーゼルエンジンの排気ガス浄化装置
JP5251711B2 (ja) 内燃機関の排気浄化装置
JP6163996B2 (ja) 診断装置
WO2014115622A1 (ja) 内燃機関の排気浄化装置
CN106661982A (zh) 排气净化系统
CN105593482B (zh) 排气净化系统
CN105556084A (zh) 诊断装置
JP6179377B2 (ja) 排気浄化装置
JP6121974B2 (ja) 内燃機関の排気浄化装置
JP6191355B2 (ja) 診断装置
JP6179378B2 (ja) 排気浄化装置
JP2015055167A (ja) 排気浄化装置
JP2017122411A (ja) 排ガス浄化システム

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 201480016697.X

Country of ref document: CN

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14753870

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

REEP Request for entry into the european phase

Ref document number: 2014753870

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 2014753870

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 14768577

Country of ref document: US