WO2019172357A1 - Dispositif d'épuration d'échappement, véhicule, et dispositif de commande d'épuration d'échappement - Google Patents

Dispositif d'épuration d'échappement, véhicule, et dispositif de commande d'épuration d'échappement Download PDF

Info

Publication number
WO2019172357A1
WO2019172357A1 PCT/JP2019/009013 JP2019009013W WO2019172357A1 WO 2019172357 A1 WO2019172357 A1 WO 2019172357A1 JP 2019009013 W JP2019009013 W JP 2019009013W WO 2019172357 A1 WO2019172357 A1 WO 2019172357A1
Authority
WO
WIPO (PCT)
Prior art keywords
exhaust
nox
exhaust gas
reduction catalyst
amount
Prior art date
Application number
PCT/JP2019/009013
Other languages
English (en)
Japanese (ja)
Inventor
洋 阿野田
Original Assignee
いすゞ自動車株式会社
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 いすゞ自動車株式会社 filed Critical いすゞ自動車株式会社
Priority to CN201980017347.8A priority Critical patent/CN111819349A/zh
Publication of WO2019172357A1 publication Critical patent/WO2019172357A1/fr

Links

Images

Classifications

    • 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
    • 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
    • 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
    • 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
    • F01N3/24—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 constructional aspects of converting 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
    • 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
    • F01N3/24—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 constructional aspects of converting apparatus
    • F01N3/28—Construction of catalytic reactors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D21/00—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas
    • F02D21/06—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air
    • F02D21/08—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air the other gas being the exhaust gas of engine
    • 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
    • F02D41/04—Introducing corrections for particular operating conditions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/14—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories in relation to the exhaust system
    • F02M26/15—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories in relation to the exhaust system in relation to engine exhaust purifying apparatus
    • 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
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
    • 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 disclosure relates to an exhaust purification device, a vehicle, and an exhaust purification control device.
  • NOx nitrogen oxide
  • An apparatus is known (see, for example, Patent Document 1).
  • the NOx selective reduction catalyst adsorbs a reducing agent (for example, ammonia) generated from a precursor (for example, urea water) supplied into the exhaust pipe, and reduces the NOx contained in the exhaust gas by the adsorbed ammonia.
  • a reducing agent for example, ammonia
  • the NOx occlusion reduction type catalyst has a property of occluded NOx at a low temperature when the NOx selective reduction type catalyst is in an inactive region. Therefore, even when the temperature is low, NOx is occluded by the NOx occlusion reduction type catalyst and then reduced. Thus, when the NOx occlusion reduction type catalyst is used together with the NOx selective reduction type catalyst in the exhaust purification device, the exhaust purification processing in the exhaust purification device can be effectively performed.
  • the exhaust gas purification apparatus may be provided with a collection unit for collecting particulate matter.
  • a collection unit for collecting particulate matter.
  • the temperature of the exhaust purification device rises.
  • the temperature in the exhaust purification device exhaust pipe
  • ammonia from the NOx selective reduction catalyst can be as much as possible. It is preferable to decrease.
  • An object of the present disclosure is to provide an exhaust purification device, a vehicle, and an exhaust purification control device capable of suppressing a reducing agent from desorbing from a NOx selective reduction catalyst due to a temperature rise in an exhaust pipe. is there.
  • An exhaust emission control device includes: An exhaust pipe through which exhaust gas generated from the internal combustion engine flows; A NOx selective reduction catalyst that is disposed in the exhaust pipe and purifies nitrogen oxides in the exhaust gas by adsorbing a reducing agent; An NOx occlusion reduction type catalyst which is disposed upstream of the NOx selective reduction type catalyst in the exhaust pipe in the exhaust direction in which the exhaust gas flows, and occludes nitrogen oxides in the exhaust gas; A recirculation path section for connecting the exhaust pipe and the exhaust pipe of the internal combustion engine from the exhaust pipe, and recirculating the exhaust gas in the exhaust pipe to the intake pipe; An adjustment unit for adjusting the flow rate of the exhaust gas recirculated in the recirculation path unit; A control unit that controls the adjusting unit so that a reduction action of the reducing agent and nitrogen oxides contained in the exhaust gas is promoted according to the amount of adsorption of the reducing agent of the NOx selective reduction catalyst; , Is provided.
  • the vehicle according to the present disclosure is The above-described exhaust purification device is provided.
  • An exhaust purification control apparatus includes: An exhaust pipe through which exhaust gas generated from an internal combustion engine flows, a NOx selective reduction catalyst that is disposed in the exhaust pipe and purifies nitrogen oxides in the exhaust gas by adsorbing a reducing agent, and the exhaust gas includes An NOx occlusion reduction type catalyst that is disposed upstream of the NOx selective reduction type catalyst in the exhaust pipe in the flowing exhaust direction and occludes nitrogen oxides in the exhaust gas, and an intake pipe of the internal combustion engine from the exhaust pipe
  • An exhaust gas purification control device for an exhaust gas purification device comprising: a recirculation path portion that connects the exhaust pipe and the exhaust pipe, and recirculates the exhaust gas in the exhaust pipe to the intake pipe, An adjustment unit for adjusting the flow rate of the exhaust gas recirculated in the recirculation path unit; A control unit that controls the adjusting unit so that a reduction action of the reducing agent and nitrogen oxides contained in the exhaust gas is promoted according to the amount of adsorption of the reducing
  • FIG. 1 is a schematic configuration diagram illustrating an exhaust system of an internal combustion engine to which an exhaust emission control device according to an embodiment of the present disclosure is applied.
  • FIG. 2 is a graph showing the temperature change of NOx storage efficiency in the NOx storage reduction catalyst.
  • FIG. 3 is a graph showing the temperature change of the NOx purification rate in the NOx selective reduction catalyst.
  • FIG. 4 is a flowchart showing an operation example of the purification control in the exhaust purification device.
  • FIG. 5 is a flowchart showing an operation example of the exhaust gas flow rate control in the recirculation path section.
  • FIG. 1 is a schematic configuration diagram illustrating an exhaust system of an internal combustion engine 1 to which an exhaust purification device 100 according to an embodiment of the present disclosure is applied.
  • the internal combustion engine 1 is, for example, a diesel engine mounted on a vehicle V, and is provided with an exhaust purification device 100 for guiding exhaust gas generated in the internal combustion engine 1 to the atmosphere.
  • the exhaust purification device 100 includes an intake pipe 110, an exhaust pipe 120, a first temperature detection unit 130, a second temperature detection unit 140, a urea water injection unit 150, a recirculation path unit 160, and a control unit 300. It has.
  • the intake pipe 110 is provided with an intake valve (not shown), and the intake pipe 110 sucks outside air into the internal combustion engine 1 by opening the intake valve under the control of the control unit 300.
  • Exhaust gas generated from the internal combustion engine 1 flows through the exhaust pipe 120.
  • a NOx occlusion reduction catalyst 210 and a DPF (capacitor) as an example of a collection unit are sequentially arranged from the upstream side in the direction in which the exhaust gas flows (the direction from the left to the right in the drawing, hereinafter referred to as “exhaust direction”).
  • the NOx occlusion reduction type catalyst 210 is disposed upstream of the DPF 220 and the NOx selective reduction type catalyst 230 in the exhaust pipe 120 in the exhaust direction, and occludes nitrogen oxides (hereinafter referred to as NOx) in the exhaust gas.
  • NOx nitrogen oxides
  • the NOx occlusion reduction type catalyst 210 occludes NOx in the exhaust gas when the exhaust temperature is the occlusion temperature and the exhaust air-fuel ratio is in a lean state.
  • the range of the occlusion temperature includes a temperature at which the NOx selective reduction catalyst 230 is in a non-activated region.
  • the NOx occluded in the NOx occlusion reduction catalyst 210 is reduced by reacting with the hydrocarbons and carbon monoxide in the exhaust gas by setting the exhaust air-fuel ratio to a rich state under the control of the control unit 300. .
  • the DPF 220 collects particulate matter contained in the exhaust gas that passes through the DPF 220.
  • the particulate matter is removed by executing a regeneration process for burning the collected particulate matter under the control of the control unit 300.
  • a regeneration process for burning the collected particulate matter under the control of the control unit 300.
  • post injection into the cylinder of the internal combustion engine 1 and fuel supply into the exhaust pipe 120 are performed, for example, hydrocarbons are supplied to an oxidation catalyst (not shown)
  • An oxidation reaction occurs in the oxidation catalyst, and the temperature of the exhaust gas in the exhaust pipe 120 rises.
  • the particulate matter is burned by the exhaust gas whose temperature has risen flowing into the DPF 220.
  • the NOx selective reduction catalyst 230 is disposed downstream of the DPF 220 in the exhaust pipe 120 and adsorbs ammonia as an example of a reducing agent generated based on the urea water injected by the urea water injection unit 150.
  • the NOx selective reduction catalyst 230 reduces the NOx by reacting the adsorbed ammonia with NOx contained in the exhaust gas passing through the NOx selective reduction catalyst 230.
  • the first temperature detection unit 130 is arranged upstream of the NOx storage reduction catalyst 210 in the exhaust direction, and detects the temperature of the front portion of the NOx storage reduction catalyst 210 in the exhaust pipe 120.
  • the second temperature detection unit 140 is arranged upstream of the NOx selective reduction catalyst 230 in the exhaust direction, and detects the temperature of the front portion of the NOx selective reduction catalyst 230 in the exhaust pipe 120.
  • the urea water injection unit 150 is disposed upstream of the NOx selective reduction catalyst 230 in the exhaust pipe 120.
  • urea water is supplied into the exhaust pipe 120 by the urea water injection unit 150, the urea water is hydrolyzed by the temperature in the exhaust pipe 120, and ammonia is generated. Then, ammonia is adsorbed on the NOx selective reduction catalyst 230.
  • the recirculation path section 160 is a path that branches from the exhaust pipe 120 and recirculates the exhaust gas in the exhaust pipe 120 toward the intake pipe 110, and is connected to the intake pipe 110 and the exhaust pipe 120.
  • the recirculation path section 160 is provided with an adjustment section 161 that adjusts the flow rate of exhaust gas that is returned from the exhaust pipe 120 to the intake pipe 110 via the recirculation path section 160.
  • the adjustment unit 161 adjusts the flow rate of the exhaust gas returned from the exhaust pipe 120 to the intake pipe 110 by changing the flow path of the exhaust gas from the open state to the closed state under the control of the control unit 300.
  • the controller 300 is, for example, an electronic control unit (ECU), and includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an input / output circuit (not shown). .
  • the control unit 300 performs a regeneration process for burning the particulate matter collected in the DPF 220 based on a preset program, a rich process for making the exhaust air-fuel ratio in the exhaust pipe 120 rich, and a recirculation path unit 160. A process for adjusting the flow rate of the exhaust gas is executed.
  • the control unit 300 corresponds to the “exhaust gas purification control device” of the present disclosure.
  • the control unit 300 estimates the ammonia adsorption amount of the NOx selective reduction catalyst 230 when executing the regeneration process of the DPF 220. Then, the control unit 300 adjusts the adjustment unit 161 so that the reduction action of ammonia adsorbed on the NOx selective reduction catalyst 230 and NOx contained in the exhaust gas is accelerated according to the estimated amount of adsorption of ammonia. To control.
  • the control unit 300 corresponds to the “estimation unit” of the present disclosure.
  • the control unit 300 estimates the NOx occlusion amount of the NOx occlusion reduction type catalyst 210.
  • the control unit 300 controls the adjustment unit 161 based on the estimated occlusion amount. It is determined whether or not to control.
  • the control unit 300 controls the adjustment unit 161 so as to reduce the flow rate of the exhaust gas in the recirculation path unit 160.
  • the predetermined target amount is, for example, the amount of ammonia that causes the ammonia slip concentration in the NOx selective reduction catalyst 230 to be equal to or less than the target value during the regeneration process.
  • the supplied ammonia amount is the amount of ammonia supplied to the NOx selective reduction catalyst 230, and is calculated based on the amount of urea water injected by the urea water injection unit 150.
  • the consumed ammonia amount is the amount of ammonia consumed in the NOx purification reaction, the amount of NOx that has passed through the NOx selective reduction catalyst 230, the temperature detection result of the second temperature detection unit 140, the flow rate of exhaust gas, Is calculated based on the ratio of NO 2 and the amount of adsorbed ammonia.
  • the amount of NOx that has passed through the NOx selective reduction catalyst 230 is detected based on a sensor or the like (not shown).
  • the ratio of NO 2 in NOx is estimated by correcting the map based on the engine speed and the fuel injection amount based on the NOx storage amount and temperature of the NOx storage reduction catalyst 210.
  • the previous adsorption amount of ammonia is the current adsorption amount of ammonia calculated last time by the equation (1).
  • the ammonia desorption amount is the amount of ammonia desorbed from the NOx selective reduction catalyst 230, and is calculated based on the ammonia adsorption amount, the temperature detection result of the second temperature detection unit 140, and the exhaust gas flow rate.
  • the estimated storage amount of NOx is estimated by the following equation (2).
  • NOx occlusion amount A + B ⁇ CDE (2)
  • the stored amount of NOx is the amount of NOx already stored in the NOx storage-reduction catalyst 210.
  • the estimated value of the stored amount of NOx estimated last time is used.
  • the upstream NOx concentration of the NOx storage reduction catalyst 210 is the NOx concentration in the exhaust gas upstream of the NOx storage reduction catalyst 210 in the exhaust pipe 120.
  • the NOx concentration detected by a sensor (not shown). Is used.
  • the NOx occlusion efficiency of the NOx occlusion reduction catalyst 210 depends on the temperature detection result of the first temperature detector 130, the exhaust gas flow rate, the NOx concentration upstream of the NOx occlusion reduction catalyst 210, the NOx occlusion amount, and the like. Calculated based on The flow rate of the exhaust gas is the amount of exhaust gas flowing into the exhaust pipe 120 and is detected by a sensor or the like (not shown).
  • the amount of NOx discharged from the NOx storage reduction catalyst 210 is calculated based on the temperature detection result of the first temperature detection unit 130, the stored amount of NOx, and the like.
  • the amount of NOx reduced from the NOx storage reduction catalyst 210 is calculated based on the temperature detection result of the first temperature detection unit 130, the exhaust gas flow rate, the already stored storage amount of the NOx storage reduction catalyst 210, the exhaust air-fuel ratio, and the like. Is done.
  • the exhaust air-fuel ratio is calculated based on the fuel injection amount in the exhaust pipe 120 and the like.
  • the adjustment unit 161 is controlled so as to reduce the flow rate of the exhaust gas in the recirculation path unit 160, so the exhaust gas returned to the intake pipe 110 by the recirculation path unit 160. Gas is reduced. Since the exhaust gas contains NOx, the concentration of NOx in the exhaust gas flowing through the exhaust pipe 120 is increased by controlling the adjustment unit 161.
  • the NOx occlusion amount of the NOx occlusion reduction type catalyst 210 can be increased, and the ammonia adsorbed on the NOx selective reduction type catalyst 230 can be reduced by the purification reaction with NOx contained in the exhaust gas.
  • control unit 300 may determine whether to control the adjustment unit 161 based on the detection result of the first temperature detection unit 130.
  • FIG. 2 is a graph showing a change in the NOx storage efficiency with temperature in the NOx storage reduction catalyst 210.
  • the NOx occlusion efficiency of the NOx occlusion reduction type catalyst 210 is relatively high occlusion efficiency, for example, in the range of temperature T1 to temperature T2. For this reason, the control unit 300 determines to control the adjustment unit 161 in such a temperature range that the occlusion efficiency is higher than the predetermined efficiency.
  • the predetermined efficiency can be appropriately determined according to the storage amount of the NOx storage reduction catalyst 210 or the like. Thereby, the storage efficiency of the NOx storage reduction catalyst 210 can be improved, and ammonia in the NOx selective reduction catalyst 230 can be reduced by the NOx contained in the exhaust gas.
  • control unit 300 may determine whether to control the adjustment unit 161 based on the detection result of the second temperature detection unit 140.
  • FIG. 3 is a graph showing the temperature change of the NOx purification rate in the NOx selective reduction catalyst 230. As shown in FIG.
  • the control part 300 determines with controlling the adjustment part 161, when it is more than the activation temperature T3.
  • the ammonia reduction efficiency of the NOx selective reduction catalyst 230 can be improved, and as a result, the ammonia of the NOx selective reduction catalyst 230 can be easily reduced.
  • control unit 300 may control the adjustment unit 161 based on the temperature of the NOx storage reduction catalyst 210 and the temperature of the NOx selective reduction catalyst 230.
  • Table 1 is a graph showing the relationship between the estimated storage amount of NOx, the temperature of the NOx storage reduction catalyst 210, the temperature of the NOx selective reduction catalyst 230, and the exhaust gas flow rate in the recirculation path section 160.
  • Estimated storage amount indicates the estimated storage amount of the NOx storage reduction catalyst 210.
  • the “first temperature” in Table 1 indicates the temperature of the NOx storage reduction catalyst 210 (temperature detection result of the first temperature detection unit 130).
  • “Second temperature” in Table 1 indicates the temperature of the NOx selective reduction catalyst 230 (temperature detection result of the second temperature detection unit 140).
  • “Flow rate” in Table 1 indicates the exhaust gas flow rate of the recirculation path section 160.
  • “large” in the “estimated storage amount” in Table 1 indicates a case where the estimated storage amount of the NOx storage reduction catalyst 210 is larger than the predetermined storage amount, and “small” indicates that the NOx storage reduction catalyst 210.
  • the case where the estimated occlusion amount is smaller than the predetermined occlusion amount is shown.
  • control unit 300 controls the adjustment unit 161 by reading the relationship shown in Table 1 from a storage unit (not shown) or the like according to conditions. By doing in this way, control of the adjustment part 161 can be simplified.
  • the flow rate of the exhaust gas flows through the recirculation path unit 160.
  • the amount is “normal” in a fully open state.
  • the flow rate of the exhaust gas is a flow rate that is “reduced” from the “normal” flow rate.
  • the degree to which the amount is reduced is determined according to the estimated storage amount, the estimated adsorption amount of ammonia, and the like.
  • the temperature of the NOx storage reduction catalyst 210 is outside the storage temperature range, and the temperature of the NOx selective reduction catalyst 230 is equal to or higher than the activation temperature (third line in Table 1), The flow rate of the exhaust gas is “decreased”.
  • the storage temperature range is, for example, a range from the temperature T1 to the temperature T2 in FIG.
  • the NOx storage reduction catalyst 210 cannot store NOx and is exhausted from the NOx storage reduction catalyst 210. This is a situation where NOx cannot be used. Therefore, in such a case, the exhaust gas in the recirculation path unit 160 can be reduced, the concentration of NOx contained in the exhaust gas in the exhaust pipe 120 can be increased, and ammonia can be reduced by using the NOx. As a result, the control as shown in the third row of Table 1 is effective.
  • the temperature of the NOx storage reduction catalyst 210 is outside the storage temperature range, and the temperature of the NOx selective reduction catalyst 230 is equal to or lower than the activation temperature (the fourth row of Table 1), The flow rate of the exhaust gas is set to “normal”.
  • the flow rate of the exhaust gas is set to “decrease”. In such a case, it is possible to promote the reduction action of NOx and ammonia contained in the exhaust gas while actively storing NOx in the NOx storage reduction catalyst 210. As a result, the control as shown in the fifth line of Table 1 is effective.
  • control unit 300 prohibits the rich process when the reproduction process is executed.
  • the NOx occlusion amount in the NOx occlusion reduction type catalyst 210 can be easily increased. That is, since the ammonia in the NOx selective reduction catalyst 230 can be easily reduced by NOx contained in the exhaust gas, the regeneration process can be executed quickly.
  • FIG. 4 is a flowchart showing an operation example of the purification control in the exhaust purification device 100. The process in FIG. 4 is appropriately executed while the vehicle V is traveling, for example.
  • the control unit 300 determines whether or not it is necessary to execute the reproduction process (step S101).
  • the determination as to whether the regeneration process in step S101 needs to be executed is based on, for example, the collected amount of particulate matter in the DPF 220. Specifically, when the trapped amount of the particulate matter in the DPF 220 reaches the amount to be burned, the control unit 300 determines that the regeneration process needs to be executed.
  • step S101 if it is not necessary to execute the reproduction process (step S101, NO), this control ends. On the other hand, when it is necessary to execute the reproduction process (step S101, YES), the control unit 300 prohibits the rich process (step S102).
  • the controller 300 estimates the ammonia adsorption amount of the NOx selective reduction catalyst 230 (step S103). Next, the control unit 300 determines whether or not the ammonia adsorption amount is larger than a predetermined target amount (step S104).
  • step S104 if the ammonia adsorption amount is larger than the predetermined target amount (step S104, YES), the control unit 300 performs exhaust gas flow rate control in the recirculation path unit 160 described later (step S105). After step S105, the process returns to step S103.
  • the control unit 300 determines whether or not the regeneration processing condition is satisfied (step S106).
  • the regeneration process condition includes, for example, the temperature condition of the NOx storage reduction catalyst 210 and the like.
  • step S106 if the reproduction processing condition is not satisfied (step S106, NO), the process returns to step S103.
  • NO in step S106, and the reason why the process returns to step S103 after step S105, the exhaust gas passes through the exhaust pipe 120 during the process from step S103 to step S106. This is because the NOx storage amount and the ammonia adsorption amount vary due to the flow.
  • step S106 when the reproduction process condition is satisfied (step S106, YES), the control unit 300 executes the reproduction process (step S107). After the reproduction process is finished, this control is finished. This control is repeatedly executed while the vehicle V is traveling.
  • FIG. 5 is a flowchart showing an operation example of the exhaust gas flow rate control in the recirculation path section 160. The process in FIG. 5 is executed when YES is determined in step S104 in FIG.
  • control unit 300 estimates the NOx occlusion amount of the NOx occlusion reduction type catalyst 210 (step S201). Next, the controller 300 determines whether or not the estimated storage amount of NOx is less than the predetermined storage amount (step S202).
  • step S202 determines whether or not the first temperature of the NOx storage reduction catalyst 210 is within a predetermined range (step S203).
  • the first temperature is, for example, a detection result of the first temperature detection unit 130.
  • the predetermined range is, for example, within the range of T1 and T2 in FIG.
  • step S203 determines whether or not the second temperature of the NOx selective reduction catalyst 230 is equal to or higher than the activation temperature (step S204).
  • the second temperature is, for example, a detection result of the second temperature detection unit 140.
  • step S204 NO
  • step S204, YES the control unit 300 controls the adjustment unit 161 to decrease the exhaust gas flow rate in the recirculation path unit 160 (step S205). Thereafter, this control ends.
  • this control ends.
  • finished a process returns to step S103 in FIG.
  • control unit 300 promotes the reduction action of ammonia and NOx contained in the exhaust gas according to the estimated ammonia adsorption amount of the NOx selective reduction catalyst 230.
  • the adjustment unit 161 is controlled.
  • ammonia in the NOx selective reduction catalyst 230 is reduced using NOx contained in the exhaust gas. As a result, it is possible to suppress the desorption of ammonia from the NOx selective reduction catalyst 230 due to the temperature rise in the exhaust pipe 120 during the regeneration process.
  • the control unit 300 adjusts the adjustment unit 161 so as to decrease the flow rate of the exhaust gas. To control. As a result, the concentration of NOx contained in the exhaust gas is increased so that NOx is stored in the NOx storage reduction catalyst 210, and the ammonia in the NOx selective reduction catalyst 230 is reduced by the NOx by the NOx contained in the exhaust gas. Can do.
  • the NOx occlusion amount is estimated using the above-described equation (2).
  • the present disclosure is not limited to this, and the NOx occlusion amount may be estimated by other methods. good.
  • sensors for detecting NOx may be provided on the upstream side and the downstream side of the NOx storage reduction catalyst 210, respectively, and the NOx storage amount may be estimated using the difference value of the detection amount of each sensor.
  • the adjustment unit 161 is controlled when the regeneration process is executed.
  • the present disclosure is not limited to this, and the temperature inside the exhaust pipe 120 is increased due to a factor other than the regeneration process. At this time, the adjustment unit 161 may be controlled.
  • the estimation unit is exemplified as the control unit 300.
  • the present disclosure is not limited to this, and the estimation unit may be provided separately from the control unit 300.
  • the exhaust emission control device 100 in the above embodiment is mounted on the vehicle V equipped with a diesel engine
  • the present disclosure is not limited to this, and may be mounted on a vehicle equipped with a gasoline engine, for example. good.
  • DPF220 was illustrated as an example of a collection part, this indication is not limited to this, What kind of thing may be used if it is a filter which can collect a particulate matter. . Further, when the exhaust gas purification device 100 is mounted on a vehicle equipped with a gasoline engine, a GPF (gasoline particulate filter) may be the collection unit.
  • GPF gasoline particulate filter
  • the exhaust purification device of the present disclosure is useful as an exhaust purification device, a vehicle, and an exhaust purification control device capable of suppressing the reduction agent from desorbing from the NOx selective reduction catalyst due to the temperature rise in the exhaust pipe. is there.

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)
  • Biomedical Technology (AREA)
  • Environmental & Geological Engineering (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Exhaust Gas Treatment By Means Of Catalyst (AREA)
  • Exhaust-Gas Circulating Devices (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)
  • Processes For Solid Components From Exhaust (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)

Abstract

La présente invention concerne un dispositif d'épuration d'échappement comprenant : un tuyau d'échappement apte à être traversé par un écoulement de gaz d'échappement produit par un moteur à combustion interne ; un catalyseur de réduction sélective des NOx disposé dans le tuyau d'échappement et destiné à purifier les oxydes d'azote dans le gaz d'échappement au moyen de l'adsorption d'un agent réducteur ; un catalyseur de réduction de stockage des NOx disposé en amont du catalyseur de réduction sélective des NOx dans le tuyau d'échappement dans une direction d'échappement de l'écoulement de gaz d'échappement, et destiné à stocker les oxydes d'azote dans le gaz d'échappement ; une unité de réglage destinée à régler le débit de gaz d'échappement retourné du tuyau d'échappement vers un tuyau d'admission du moteur à combustion interne ; et une unité de commande destinée à commander l'unité de réglage de sorte que la réaction de réduction entre l'agent réducteur et les oxydes d'azote contenus dans le gaz d'échappement soit favorisée en fonction de la quantité d'adsorption de l'agent réducteur du catalyseur de réduction sélective des NOx.
PCT/JP2019/009013 2018-03-08 2019-03-07 Dispositif d'épuration d'échappement, véhicule, et dispositif de commande d'épuration d'échappement WO2019172357A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201980017347.8A CN111819349A (zh) 2018-03-08 2019-03-07 废气净化装置、车辆以及废气净化控制装置

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2018041868A JP2019157667A (ja) 2018-03-08 2018-03-08 排気浄化装置、車両および排気浄化制御装置
JP2018-041868 2018-03-08

Publications (1)

Publication Number Publication Date
WO2019172357A1 true WO2019172357A1 (fr) 2019-09-12

Family

ID=67846517

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2019/009013 WO2019172357A1 (fr) 2018-03-08 2019-03-07 Dispositif d'épuration d'échappement, véhicule, et dispositif de commande d'épuration d'échappement

Country Status (3)

Country Link
JP (1) JP2019157667A (fr)
CN (1) CN111819349A (fr)
WO (1) WO2019172357A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2022003248A (ja) * 2020-06-23 2022-01-11 いすゞ自動車株式会社 浄化制御装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006274844A (ja) * 2005-03-28 2006-10-12 Mitsubishi Fuso Truck & Bus Corp 内燃機関の排気浄化装置
JP2010112345A (ja) * 2008-11-10 2010-05-20 Mitsubishi Motors Corp 排気浄化装置
JP2015014215A (ja) * 2013-07-03 2015-01-22 トヨタ自動車株式会社 内燃機関の排気浄化装置
JP2018021475A (ja) * 2016-08-02 2018-02-08 マツダ株式会社 エンジンの排気浄化装置

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4265497B2 (ja) * 2004-07-05 2009-05-20 トヨタ自動車株式会社 排気浄化装置の制御方法
JP4905327B2 (ja) * 2007-11-13 2012-03-28 トヨタ自動車株式会社 内燃機関の排気浄化システム
JP2013241859A (ja) * 2012-05-18 2013-12-05 Isuzu Motors Ltd 排気ガス浄化システム及び排気ガス浄化方法
JP6323354B2 (ja) * 2015-01-30 2018-05-16 トヨタ自動車株式会社 内燃機関の排気浄化装置

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006274844A (ja) * 2005-03-28 2006-10-12 Mitsubishi Fuso Truck & Bus Corp 内燃機関の排気浄化装置
JP2010112345A (ja) * 2008-11-10 2010-05-20 Mitsubishi Motors Corp 排気浄化装置
JP2015014215A (ja) * 2013-07-03 2015-01-22 トヨタ自動車株式会社 内燃機関の排気浄化装置
JP2018021475A (ja) * 2016-08-02 2018-02-08 マツダ株式会社 エンジンの排気浄化装置

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2022003248A (ja) * 2020-06-23 2022-01-11 いすゞ自動車株式会社 浄化制御装置
JP7310730B2 (ja) 2020-06-23 2023-07-19 いすゞ自動車株式会社 浄化制御装置

Also Published As

Publication number Publication date
CN111819349A (zh) 2020-10-23
JP2019157667A (ja) 2019-09-19

Similar Documents

Publication Publication Date Title
JP6508229B2 (ja) 内燃機関の排気浄化装置の異常診断装置
EP3051089B1 (fr) Appareil de purification d'échappement pour moteur à combustion interne
USRE48658E1 (en) Exhaust gas purification apparatus for an internal combustion engine
US8978367B2 (en) Exhaust gas purifying system of internal combustion engine
US7565799B2 (en) Controlling lean NOx trap (LNT) catalyst performance
JP2009264181A (ja) 内燃機関の排気浄化装置
JP5804544B2 (ja) 内燃機関の排気処理装置
WO2019172356A1 (fr) Dispositif d'épuration des gaz d'échappement, véhicule et dispositif de commande d'épuration des gaz d'échappement
JP2010209737A (ja) 内燃機関の排気浄化装置
JP5983438B2 (ja) 内燃機関の排気浄化装置
JP4935929B2 (ja) 内燃機関の排気浄化装置
WO2019172357A1 (fr) Dispositif d'épuration d'échappement, véhicule, et dispositif de commande d'épuration d'échappement
JP5761255B2 (ja) 内燃機関の排気浄化装置
WO2016132875A1 (fr) Système de purification de gaz d'échappement pour moteur à combustion interne, moteur à combustion interne et procédé de purification de gaz d'échappement pour moteur à combustion interne
JP2006348905A (ja) 内燃機関の排気浄化システム
JP5488493B2 (ja) 内燃機関の排気浄化装置
JP2008121555A (ja) 内燃機関の排気浄化装置
JP4893493B2 (ja) 内燃機関の排気浄化装置
JP2016205351A (ja) 内燃機関の排気浄化制御システム
JP5052208B2 (ja) 内燃機関の排気浄化装置
JP6500636B2 (ja) エンジンの排気浄化装置
JP4765685B2 (ja) 内燃機関の排気浄化システム
JP2009264311A (ja) 内燃機関の排気浄化装置
JP4720748B2 (ja) 内燃機関の排気浄化システム
JP6686516B2 (ja) Ｌｎｔを用いた排ガス処理方法およびその装置

Legal Events

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

Ref document number: 19764548

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19764548

Country of ref document: EP

Kind code of ref document: A1