WO2012157066A1 - Appareil de purification des gaz d'échappement pour moteur à combustion interne - Google Patents

Appareil de purification des gaz d'échappement pour moteur à combustion interne Download PDF

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Publication number
WO2012157066A1
WO2012157066A1 PCT/JP2011/061192 JP2011061192W WO2012157066A1 WO 2012157066 A1 WO2012157066 A1 WO 2012157066A1 JP 2011061192 W JP2011061192 W JP 2011061192W WO 2012157066 A1 WO2012157066 A1 WO 2012157066A1
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WIPO (PCT)
Prior art keywords
reducing agent
injection valve
exhaust
mass
exhaust gas
Prior art date
Application number
PCT/JP2011/061192
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English (en)
Japanese (ja)
Inventor
伊藤　和浩
中山　茂樹
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トヨタ自動車株式会社
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Priority to PCT/JP2011/061192 priority Critical patent/WO2012157066A1/fr
Publication of WO2012157066A1 publication Critical patent/WO2012157066A1/fr

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
    • F01N3/2066—Selective catalytic reduction [SCR]
    • 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
    • F01N3/36—Arrangements for supply of additional fuel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • 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
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Definitions

  • the present invention relates to an exhaust purification device for an internal combustion engine.
  • An exhaust emission control device that purifies NOx by supplying urea water (NH 3 ) in an amount corresponding to the estimated NOx generation amount to a selective reduction type NOx catalyst is known (see, for example, Patent Document 1). .
  • the attachment position of the injection valve, the injection hole shape, and the like are determined so that urea water (NH 3 ) is uniformly distributed in the exhaust pipe.
  • the NOx distribution in the exhaust gas may not be uniform due to the influence of the shape of the exhaust pipe. That is, the NOx distribution and the reducing agent distribution in the exhaust gas may deviate. For this reason, there is a possibility that the reducing agent is insufficient at locations where the NOx concentration in the exhaust is high, and the reducing agent becomes excessive at locations where the NOx concentration is low. As a result, the NOx purification rate may decrease, or NH 3 remaining in the catalyst without being used for NOx purification may be biased and adsorbed to the catalyst. Furthermore, there is a possibility that NH 3 may slip through the catalyst.
  • a technique for measuring five parameters of exhaust flow rate, exhaust temperature, mixture temperature, mixture pressure, and atmospheric humidity, weighting each parameter, and supplying a reducing agent based on the weighted five parameters (For example, refer to Patent Document 2).
  • weighting of five parameters is learned so that the NOx distribution and the reducing agent distribution are matched.
  • a plurality of reducing agent injection valves are provided. The supply amount of the reducing agent from each injection valve is controlled according to the NOx distribution.
  • the present invention has been made in view of the above-described problems, and an object thereof is to appropriately supply a reducing agent.
  • an exhaust gas purification apparatus for an internal combustion engine comprises: A catalyst provided in the exhaust passage of the internal combustion engine; A supply device for supplying a reducing agent to the catalyst; An exhaust gas purification apparatus for an internal combustion engine comprising: The supply device supplies the reducing agent toward a place where the mass of the exhaust gas is larger than a place where the mass of the exhaust gas is small.
  • the exhaust density is not uniform, and there are places where the exhaust density is high and low. Then, the mass per unit volume is relatively large at locations where the exhaust density is high, and the mass per unit volume is relatively small at locations where the exhaust density is low. That is, the location where the exhaust mass is small may be a location where the exhaust density is relatively low. Further, the location where the mass of the exhaust is large may be a location where the density of the exhaust is relatively high. Further, the location where the exhaust mass is small and the location where the exhaust mass is large may be the location where the mass of the exhaust is the smallest and the location where the mass is the largest. That is, the reducing agent may be supplied toward a location where the mass of exhaust gas is the largest.
  • the portion where the mass of exhaust gas is large contains more components to be purified than the portion where the mass of exhaust gas is small. For this reason, in the location where the mass of exhaust gas is large, more reducing agent is required.
  • the reducing agent toward a location where the mass of the exhaust gas is large, it is possible to supply more reducing agent to a location where more components to be purified are contained. Thereby, purification efficiency can be improved. Further, the supply amount of the reducing agent can be reduced. Moreover, since it becomes possible to supply the reducing agent according to the amount of the component to be purified, it is possible to suppress the excess reducing agent from adhering to the catalyst and reducing the purification rate. Moreover, it can suppress that an excessive reducing agent passes a catalyst. In this way, the reducing agent can be properly supplied.
  • the supply device includes an injection valve that injects the reducing agent
  • the injection valve may be formed with an injection hole for injecting a reducing agent toward a portion where the mass of the exhaust gas is large.
  • the injection valve includes one or a plurality of injection holes, and the injection holes are formed so that the center of gravity of the reducing agent injected from each injection hole passes through a portion where the mass of the exhaust gas is large. May be.
  • the reducing agent is dispersed in a wider range.
  • concentration of the reducing agent is high and there are places where it is low.
  • a place where the concentration of the reducing agent is high may be formed on the center side of the spray, or may be formed on the outer side. is there.
  • more reducing agent exists around the center of gravity of the injected reducing agent.
  • the position of the center of gravity of the reducing agent may vary depending on the shape of the nozzle hole. For this reason, if the nozzle hole is formed so that the center of gravity of the reducing agent passes through a portion where the mass of the exhaust gas is large, more reducing agent can be supplied to a portion where there are more components to be purified.
  • each nozzle hole is formed so that a portion where the spray of the reducing agent injected from each nozzle hole passes through a portion where the mass of the exhaust gas is larger. May be. That is, since the concentration of the reducing agent is higher in the areas where the sprays overlap than in the areas where the sprays do not overlap, more reducing agent can be supplied. Moreover, you may form an injection hole so that the reducing agent injected from each injection hole may each pass through the location where the mass of exhaust_gas
  • the center of gravity may be the mass center of the mass distribution of the reducing agent at a predetermined distance from the injection valve.
  • a plurality of the injection valves may be provided, and the injection valves may be arranged so that the reducing agent injected from each injection valve overlaps at a location where the mass of the exhaust gas is large.
  • the number of injection holes of each injection valve may be one or plural.
  • the place where the concentration of the reducing agent is high may be formed on the center side of the spray, or may be formed on the outer side.
  • the attachment position of each injection valve may be adjusted so that the position where the reducing agent injected from each injection valve overlaps becomes the mass center of the mass distribution of the reducing agent.
  • the reducing agent can be properly supplied.
  • FIG. 1 is a diagram illustrating a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to a first embodiment. It is the figure which illustrated the form of spraying of the injection valve concerning Example 1. It is the figure which showed an example of the relationship between the mass distribution of the exhaust_gas
  • FIG. 5 is a diagram illustrating a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to a second embodiment.
  • FIG. 6 is a diagram illustrating a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to a third embodiment.
  • FIG. 5 is a diagram illustrating a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to a second embodiment.
  • FIG. 6 is a diagram illustrating a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to
  • FIG. 10 is a diagram illustrating a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to a fourth embodiment.
  • FIG. 10 is a diagram illustrating a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to a fourth embodiment.
  • FIG. 10 is a diagram illustrating a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to a fourth embodiment.
  • FIG. 10 is a diagram illustrating a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to a fourth embodiment.
  • FIG. 10 is a diagram illustrating a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to a fourth embodiment. It is a figure which shows schematic structure of the conventional injection valve. It is a figure which shows schematic structure of the injection valve which concerns on Example 5.
  • FIG. It is a figure which shows schematic structure of the other injection valve which concerns on Example 5.
  • FIG. It is a figure which shows schematic structure of the injection valve provided with one injection hole. It is a figure which shows
  • FIG. 1 is a diagram showing a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to the present embodiment.
  • the internal combustion engine 1 shown in FIG. 1 is a water-cooled four-cycle diesel engine having four cylinders.
  • the following embodiments can be similarly applied even to a gasoline engine.
  • the exhaust passage 2 is connected to the internal combustion engine 1.
  • An injection valve 3 and a catalyst 4 are provided in the exhaust passage 2 in order from the upstream side in the exhaust flow direction.
  • the injection valve 3 injects a reducing agent.
  • a reducing agent derived from ammonia such as fuel (HC) or urea water can be used. What is used as the reducing agent depends on the type of the catalyst 4. Then, the reducing agent reacts with the catalyst 4.
  • the injection hole of the injection valve 3 can be formed so that the spray R of the injection valve 3 has the following shape.
  • FIG. 2 is a diagram illustrating the form of the spray R of the injection valve 3 according to the present embodiment.
  • FIG. 2 shows a cross-sectional shape of the spray R of the reducing agent injected from the injection valve 3.
  • This cross section is a cross section orthogonal to the central axis of the injection valve 3 at a predetermined distance from the injection valve 3.
  • the inside of the region surrounded by the solid line indicates the range where the spray R from each nozzle hole exists.
  • the broken line indicates the tip of the injection valve 3.
  • FIG. 2A shows a case where three nozzle holes are provided.
  • three injection holes are arranged at equal intervals around the central axis of the injection valve 3. Therefore, three sprays R are formed at an equal angle around the central axis of the injection valve 3.
  • FIG. 2 (B) and FIG. 2 (C) are cases where four nozzle holes are provided.
  • four injection holes are arranged at equal intervals around the central axis of the injection valve 3.
  • four sprays R are formed at equal angles around the central axis of the injection valve 3.
  • three injection holes are arranged at equal intervals around the central axis of the injection valve 3, and further one is arranged on the central axis of the injection valve 3. Therefore, three sprays R are formed at an equal angle around the central axis of the injection valve 3, and one spray R is formed on the central axis of the injection valve 3.
  • FIG. 2 (D) and 2 (E) show a case where five nozzle holes are provided.
  • FIG. 2D five injection holes are arranged at equal intervals around the central axis of the injection valve 3.
  • five sprays R are formed at equal angles around the central axis of the injection valve 3.
  • FIG. 2 (E) four injection holes are arranged at equal intervals around the central axis of the injection valve 3, and one further is arranged on the central axis of the injection valve 3.
  • four sprays R are formed at an equal angle around the central axis of the injection valve 3, and one spray R is formed on the central axis of the injection valve 3.
  • FIG. 2 (F) and FIG. 2 (G) are cases where six nozzle holes are provided.
  • FIG. 2 (F) six injection holes are arranged at equal intervals around the central axis of the injection valve 3.
  • six sprays R are formed at equal angles around the central axis of the injection valve 3.
  • FIG. 2G five injection holes are arranged at equal intervals around the central axis of the injection valve 3, and further one is arranged on the central axis of the injection valve 3. Therefore, five sprays R are formed at equal angles around the central axis of the injection valve 3, and one spray R is formed on the central axis of the injection valve 3.
  • FIG. 2 (H) shows a case where seven nozzle holes are provided.
  • six injection holes are arranged at equal intervals around the central axis of the injection valve 3, and one further is arranged on the central axis of the injection valve 3.
  • six sprays R are formed at equal angles around the central axis of the injection valve 3, and one spray R is formed on the central axis of the injection valve 3.
  • the center of gravity of the reducing agent is on an extension line of the central axis of the injection valve 3.
  • This center of gravity may be the center of gravity or the center of mass of the reducing agent present in the cross section orthogonal to the central axis. That is, it is good also as a mass center of mass distribution of the spray R shown in FIG.
  • the center of gravity of the reducing agent may not be on an extension line of the central axis of the injection valve 3.
  • the injection hole of the injection valve 3 may be one or two.
  • the catalyst 4 examples include an occlusion reduction type NOx catalyst, a selective reduction type NOx catalyst, an oxidation catalyst, and a three-way catalyst. Further, the catalyst 4 may be carried on a particulate filter. Further, a particulate filter may be provided upstream or downstream of the catalyst 4.
  • the internal combustion engine 1 configured as described above is provided with an ECU 10 that is an electronic control unit for controlling the internal combustion engine 1.
  • the ECU 10 controls the operation state of the internal combustion engine 1 according to the operation conditions of the internal combustion engine 1 and the request of the driver.
  • the ECU 10 is connected to an accelerator opening sensor 12 capable of detecting an engine load by outputting an electric signal corresponding to the amount of depression of the accelerator pedal 11, and a crank position sensor 13 for detecting the engine speed via electric wiring. Output signals from these sensors are input to the ECU 10.
  • the injection valve 3 is connected to the ECU 10 via electric wiring, and the injection valve 3 is controlled by the ECU 10.
  • the injection valve 3 is assumed to inject urea water
  • the catalyst 4 is a selective reduction type NOx catalyst. Then, the urea water injected from the injection valve 3 is hydrolyzed by the heat of the exhaust gas to become ammonia (NH 3 ), and part or all of the urea water is adsorbed on the catalyst 4. This ammonia selectively reduces NOx. Then, ammonia is supplied to the catalyst 4 or adsorbed in advance, and the NOx is reduced when NOx passes through the catalyst 4.
  • the exhaust density may vary depending on the location. That is, the mass per unit volume may vary depending on the location. For this reason, mass distribution arises. And in a location where mass is large, there are more NOx, HC, and CO than in a small location. For this reason, the amounts of NOx, HC, and CO flowing into the catalyst 4 are not uniform, and deviation occurs depending on the shape of the exhaust passage 2 and the like. In the catalyst 4, there are a portion where the exhaust mass is large and a portion where the exhaust mass is small. Therefore, when the reducing agent is uniformly supplied to the catalyst 4, excess or deficiency of the reducing agent may occur depending on the location. .
  • an amount of reducing agent corresponding to the mass of exhaust gas that is, the amount of NOx, HC, CO can be supplied. it can.
  • FIG. 3 is a diagram showing an example of the relationship between the mass distribution of the exhaust gas in the exhaust passage 2 and the spray R of the reducing agent injected from the injection valve 3.
  • FIG. 3 is a cross section cut by a plane orthogonal to the central axis of the exhaust passage 2.
  • An inner region surrounded by a broken line in FIG. 3 is a portion A where the mass of the exhaust gas is relatively large, and a region outside the broken line in FIG. 3 is a portion B where the mass of the exhaust gas is relatively small.
  • the center of the location A where the exhaust mass is relatively large is assumed to be substantially equal to the central axis of the exhaust passage 2.
  • the mass of exhaust gas may be the mass of exhaust gas per unit volume.
  • the injection valve 3 is attached so that the reducing agent is supplied toward the location A where the mass of the exhaust gas is relatively large.
  • the injection valve 3 is attached so that the central axis of the injection valve 3 and the central axis of the exhaust passage 2 downstream of the injection valve 3 coincide.
  • the central axis of the injection valve 3 and the central axis of the exhaust passage 2 can be matched by using a portion where the exhaust passage 2 is bent.
  • the center of gravity of the reducing agent injected from the injection valve 3 exists on the central axis of the exhaust passage 2. That is, the center of gravity of the reducing agent passes through the portion A where the mass of the exhaust gas is relatively large.
  • the concentration of the reducing agent is relatively high at and around the center of gravity of the reducing agent. For this reason, more reducing agent can be supplied to the location A where the mass of the exhaust gas is relatively large.
  • the attachment position and the injection hole shape of the injection valve 3 may be adjusted so that the locations where the respective sprays R overlap each other pass the location A where the mass of the exhaust gas is relatively large.
  • the direction of the central axis of the injection valve 3 and the flow direction of the exhaust need not be parallel. That is, it is only necessary that the center of gravity of the reducing agent passes through the location A where the exhaust mass is relatively large.
  • the injection hole of the injection valve 3 may be directed to the location A where the mass of the exhaust gas is relatively large.
  • the injection valve 3 may be formed with an injection hole for injecting the reducing agent toward the location A where the mass of the exhaust gas is relatively large.
  • the location A where the exhaust mass is relatively large may be displaced from the central axis of the exhaust passage 2.
  • the attachment position of the injection valve 3 or the injection hole shape is adjusted according to the location A where the mass of the exhaust gas is relatively large.
  • the mass distribution of the exhaust can be obtained in advance by experiments or simulations. Further, the exhaust gas mass distribution may change depending on the operating state of the internal combustion engine 1. For example, the exhaust mass distribution in a predetermined operation state is obtained, and the injection valve 3 is installed in accordance with the exhaust mass distribution. Then, the reducing agent is supplied in a predetermined operation state.
  • the operating state is determined based on, for example, the engine speed and the engine load. This operation state may be an operation state in which the reducing agent can be supplied.
  • the center of gravity of the reducing agent or the part where the sprays R overlap each other passes through the part A where the mass of the exhaust gas is relatively large. To do.
  • the exhaust mass is relatively larger than the location B where the exhaust amount is relatively small. More A reducing agent is supplied to the location A.
  • FIG. 4 is a diagram showing an example of the mass distribution of the exhaust when the catalyst 4 is viewed from the upstream side of the exhaust passage 2. This mass distribution is on the upstream end face of the catalyst 4.
  • An inner region surrounded by a broken line in FIG. 4 is a portion A where the mass of the exhaust gas is relatively large, and a region outside the broken line in FIG. 4 is a portion B where the mass of the exhaust gas is relatively small.
  • the mass of exhaust gas may be the mass of exhaust gas per unit volume.
  • FIG. 4 there is a deviation between the center axis C of the catalyst 4 and the center D where the exhaust mass is relatively large. For example, if the exhaust passage 2 is bent just upstream of the catalyst 4, centrifugal force acts on the exhaust, resulting in a mass distribution as shown in FIG. 4.
  • the mounting position, the injection hole shape, and the number of injection holes of the injection valve 3 are adjusted so that more reducing agent is supplied to the location A where the exhaust mass is relatively large.
  • the injection valve 3 may be attached to a portion where the cross-sectional area of the exhaust passage 2 increases toward the downstream side, and the reducing agent may be injected therefrom in parallel with the central axis of the catalyst 4.
  • a reducing agent can be supplied according to the amount of components to be purified.
  • a NOx catalyst is used as the catalyst 4 and urea water is used as the reducing agent
  • a larger amount of ammonia can be adsorbed in a portion where a lot of NOx passes, so that the NOx purification rate can be improved. it can.
  • ammonia can be prevented from passing through the catalyst 4.
  • HC is supplied as a reducing agent, it is possible to suppress the HC from adhering to the catalyst 4 and preventing the exhaust gas from being purified. Furthermore, deterioration due to the temperature rise of the catalyst 4 can be suppressed. Moreover, it can suppress that the catalyst 4 is clogged with a particulate matter.
  • FIG. 5 is a diagram showing a schematic configuration of the exhaust gas purification apparatus for an internal combustion engine according to the present embodiment.
  • FIG. 5A is a view showing the arrangement of the device
  • FIG. 5B is a view of the exhaust passage 2 where the injection valve 3 is attached as viewed from the upstream side.
  • symbol is attached
  • an oxidation catalyst 41 and a particulate filter 42 are provided upstream of the injection valve 3.
  • a selective reduction type NOx catalyst 43 is provided downstream of the injection valve 3.
  • the injection valve 3 is attached to a location where the exhaust passage 2 between the particulate filter 42 and the selective reduction type NOx catalyst 43 is narrowed.
  • the injection valve 3 is attached so that its central axis is orthogonal to the central axis of the exhaust passage 2.
  • the injection hole of the injection valve 3 is formed so that the concentration of the reducing agent injected from the injection valve 3 is high on the central axis of the injection valve 3 and decreases as the distance from the central axis increases. It is assumed that the portion where the mass of the exhaust is relatively large is on the central axis of the exhaust passage 2.
  • the injection valve 3 can be attached even if the particulate filter 42 and the selective reduction type NOx catalyst 43 are close to each other. Moreover, since the disturbance of the exhaust gas becomes large at the location where the exhaust passage 2 is narrowed, atomization of the reducing agent can be promoted.
  • FIG. 6 is a diagram showing a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to the present embodiment.
  • FIG. 6A is a diagram showing the arrangement of the apparatus
  • FIG. 6B is a diagram of the particulate filter 42 viewed from the downstream side of the particulate filter 42.
  • symbol is attached
  • the injection valve 3 is attached so that the spray R from the injection valve 3 collides with the downstream end face of the particulate filter 42. For this reason, the injection valve 3 is attached to a portion downstream of the particulate filter 42 and having a smaller sectional area of the exhaust passage 2 toward the downstream side.
  • the portion where the mass of the exhaust is relatively large is on the central axis of the exhaust passage 2. Then, the reducing agent injection direction is determined so that the center of gravity of the reducing agent passes through a point where the downstream end surface of the particulate filter 42 and the central axis of the exhaust passage 2 intersect.
  • the injection valve 3 can be attached even if the particulate filter 42 and the selective reduction type NOx catalyst 43 are close to each other. Further, since the temperature of the end face of the particulate filter 42 is high due to the heat of exhaust gas, for example, hydrolysis of urea water can be promoted.
  • FIG. 7 to 11 are diagrams showing a schematic configuration of an exhaust gas purification apparatus for an internal combustion engine according to the present embodiment.
  • FIG. 7A, FIG. 8A, and FIG. 9A are views of the catalyst 4 viewed from the lateral direction.
  • 7B, FIG. 8B, FIG. 9B, FIG. 10, and FIG. 11 are views of the catalyst 4 viewed from the upstream side of the catalyst 4.
  • FIG. 11 shows the shapes of the sprays R, R1, and R2 when the exhaust passage 2 is assumed to be absent. .
  • the cross section of the catalyst 4 orthogonal to the exhaust flow direction is relatively long in one direction (vertical direction) and relatively short in the other direction (horizontal direction) orthogonal to the one direction.
  • the cross-sectional shape of the catalyst 4 may be oval or rectangular.
  • the central axis of the exhaust passage 2 is shifted between the upstream side and the downstream side of the catalyst 4. That is, the exhaust passage 2 upstream of the catalyst 4 is located above the central axis of the catalyst 4, and the exhaust passage 2 downstream of the catalyst 4 is located below the central axis of the catalyst 4. Yes.
  • the mass of the exhaust gas and the mass of the reducing agent tend to vary depending on the location.
  • the injection valve 3 is attached to the straight portion of the exhaust passage 2 upstream from the catalyst 4.
  • the straight portion of the exhaust passage 2 is located upstream of the portion where the cross-sectional area of the exhaust passage 2 increases toward the downstream side in accordance with the shape of the catalyst 4.
  • the injection valve 3 is attached so that its central axis is orthogonal to the central axis of the exhaust passage 2. It is assumed that the portion where the mass of the exhaust is relatively large is on the central axis of the exhaust passage 2.
  • the exhaust emission control device configured as described above, it is possible to supply more reducing agent to a location where the mass of the exhaust is relatively large. Further, even if the cross-sectional area of the exhaust passage 2 is increased immediately upstream of the catalyst 4 toward the downstream side, a reducing agent corresponding to the mass of the exhaust gas flowing into the catalyst 4 is supplied. Moreover, a reducing agent can be supplied also to a location where the mass of exhaust gas is relatively small. Thus, the reducing agent can be supplied according to the mass of the exhaust.
  • the injection valve 3 is mounted on the upstream side of the catalyst 4 and on the downstream side of the portion where the cross section of the exhaust passage 2 becomes larger toward the downstream side. Then, the reducing agent is injected in parallel with the upstream end face of the catalyst 4 and in the major axis direction of the upstream end face. Further, as shown in FIG. 8 (B), the spray R1 near the extension line of the central axis of the injection valve 3 has a relatively high concentration, and the spray at a position away from the extension line of the central axis of the injection valve 3. A nozzle hole is formed so that the concentration of R2 is relatively low. That is, the concentration is higher on the center side of the spray. It is assumed that a portion having a relatively large exhaust mass is formed along the long axis of the catalyst 4.
  • two injection valves 3 are mounted on the upstream side of the catalyst 4 and on the downstream side of the portion where the cross section of the exhaust passage 2 becomes larger on the downstream side. And in each injection valve 3, the reducing agent is injected in parallel with the upstream end face of the catalyst 4 and in the major axis direction of the upstream end face. In addition, nozzle holes and the like are formed so that the spray R from each injection valve 3 is uniform.
  • the concentration of the reducing agent increases because more reducing agent exists at the locations where the sprays R overlap.
  • more reducing agent can be supplied to locations where the exhaust mass is relatively large.
  • a reducing agent can be supplied also to another location.
  • the reducing agent can be supplied according to the mass of the exhaust.
  • the injection valve 3 is attached on the upstream side of the catalyst 4 and on the downstream side of the portion where the cross section of the exhaust passage 2 becomes larger toward the downstream side. Further, the injection valve 3 injects a reducing agent in a diagonal direction parallel to the upstream end face of the upstream end face of the catalyst 4. Further, the spray R1 near the extension of the central axis of the injection valve 3 has a relatively high concentration, and the spray R2 away from the extension of the central axis of the injection valve 3 has a relatively low concentration. A nozzle hole or the like is formed.
  • two injection valves 3 are attached opposite to the upstream side of the catalyst 4 and the downstream side of the portion where the cross section of the exhaust passage 2 becomes larger toward the downstream side. Further, the injection valve 3 injects a reducing agent in a diagonal direction parallel to the upstream end face of the upstream end face of the catalyst 4. In addition, nozzle holes and the like are formed so that the spray R from each injection valve 3 is uniform.
  • the exhaust gas purification apparatus configured as described above, since a larger amount of the reducing agent is present at the portion where the spray R overlaps, more reducing agent can be supplied to the portion where the mass of the exhaust gas is relatively large. Moreover, a reducing agent can be supplied also to another location. Thus, the reducing agent can be supplied according to the mass of the exhaust.
  • FIG. 12 is a diagram showing a schematic configuration of a conventional injection valve 3.
  • FIG. 12A is a cross-sectional view when the tip of the injection valve 3 is cut along the central axis
  • FIG. 12B is a diagram of the tip of the injection valve 3 as viewed from an extension line of the central axis.
  • FIG. 12C shows the concentration distribution of the reducing agent at a predetermined distance from the injection valve 3.
  • the injection hole 31 of the injection valve 3 is formed so that the cross section orthogonal to the central axis of the injection valve 3 is rectangular.
  • the rectangular length of this cross section is longer toward the tip side of the injection valve 3.
  • the width of the rectangle of the cross section is constant.
  • the spray R is formed at a predetermined angle.
  • the angles of the nozzle hole 31 and the spray R are smaller than the angles of the nozzle hole 31 and the spray R shown in FIG.
  • FIG. 13 is a diagram showing a schematic configuration of the injection valve 3 according to the present embodiment.
  • FIG. 13A is a cross-sectional view when the tip of the injection valve 3 is cut along the central axis
  • FIG. 13B is a view of the tip of the injection valve 3 as viewed from an extension line of the central axis.
  • FIG. 13C is a view showing the concentration distribution of the reducing agent at a predetermined distance from the injection valve 3.
  • the injection hole 31 is formed so that the angle of the injection hole 31 and the spray R is larger than that of the injection valve 3 shown in FIG. That is, comparing the injection valve 3 shown in FIG. 12 with a cross-sectional shape, the injection valve 3 shown in FIG. Note that the rectangular width of the cross section is the same as that shown in FIG.
  • the reducing agent peels from the nozzle hole 31 when the reducing agent passes through the nozzle hole 31.
  • more reducing agent flows through the central axis side of the injection valve 3.
  • a spray R1 having a relatively high concentration is formed on the extension line of the central axis of the injection valve 3
  • a spray R2 having a relatively low concentration is formed at both ends.
  • the concentration of the reducing agent on the extension line of the central axis of the injection valve 3 can be increased.
  • by directing the injection hole 31 to a location where the mass of the exhaust is large most of the injected reducing agent is directed to a location where the mass of the exhaust is large.
  • the concentration of the reducing agent on the extension line of the central axis of the injection valve 3 can be increased by setting the angle of the injection hole 31 so that the reducing agent is peeled off from the wall surface of the injection hole 31.
  • FIG. 14 is a diagram showing a schematic configuration of another injection valve 3 according to the present embodiment.
  • FIG. 14A is a cross-sectional view when the tip of the injection valve 3 is cut along the central axis
  • FIG. 14B is a diagram of the tip of the injection valve 3 as viewed from an extension line of the central axis.
  • FIG. 14C shows the concentration distribution of the reducing agent at a predetermined distance from the injection valve 3.
  • the injection hole 31 is provided at a position shifted from the central axis of the injection valve 3. Thereby, the spray R1 having a relatively high concentration is formed on the center side, and the spray R2 having a relatively low concentration is formed on both ends. In this way, the concentration of the reducing agent on the extension line of the injection hole 31 of the injection valve 3 can be increased. Then, by directing the injection hole 31 to a location where the mass of the exhaust is large, most of the injected reducing agent is directed to a location where the mass of the exhaust is large. For this reason, more reducing agent can be supplied to the location where the mass of exhaust gas is large.
  • FIG. 15 is a diagram showing a schematic configuration of the injection valve 3 having one injection hole 31.
  • FIG. 15A is a cross-sectional view when the tip of the injection valve 3 is cut along the central axis, and
  • FIG. 15B shows the concentration distribution of the reducing agent at a predetermined distance from the injection valve 3. It is.
  • the injection valve 3 shown in FIG. 15 is formed such that the reducing agent advances in the direction of the arrow in FIG. If it does so, more reducing agents will distribute
  • FIG. Thereby, the spray R2 having a relatively low concentration is formed on the extended line of the central axis of the injection valve 3, and the spray R1 having a relatively high concentration is formed around the spray R2.
  • FIG. 16 is a diagram showing a schematic configuration of another injection valve 3 having one injection hole 31.
  • FIG. 16A is a cross-sectional view when the tip of the injection valve 3 is cut along the central axis
  • FIG. 16B shows the concentration distribution of the reducing agent at a predetermined distance from the injection valve 3. It is.
  • the injection valve 3 shown in FIG. 16 is formed such that the reducing agent advances in the direction of the arrow in FIG. If it does so, more reducing agents will distribute
  • FIG. As a result, a spray R1 having a relatively high concentration is formed on the extension line of the central axis of the injection valve 3, and a spray R2 having a relatively low concentration is formed therearound.
  • the concentration distribution of the reducing agent also changes depending on the shape of the injection valve 3. Then, by directing the nozzle hole 31 to a location where the mass of the exhaust is large, most of the injected reducing agent is directed to a location where the mass of the exhaust is large. For this reason, more reducing agent can be supplied to the location where the mass of exhaust gas is large.

Landscapes

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

Abstract

En vue de fournir un agent réducteur de façon appropriée dans un appareil de purification des gaz d'échappement pour un moteur à combustion interne, ledit appareil de purification des gaz d'échappement comprend un catalyseur disposé dans un conduit d'échappement du moteur à combustion interne et un appareil de fourniture pour la fourniture de l'agent réducteur au catalyseur, l'appareil de fourniture fournissant plutôt l'agent réducteur en direction d'un emplacement présentant une masse plus importante de gaz d'échappement que vers un emplacement présentant une masse moins importante de gaz d'échappement. Une quantité appropriée de l'agent réducteur au vu de la masse de gaz d'échappement peut ainsi être fournie.
PCT/JP2011/061192 2011-05-16 2011-05-16 Appareil de purification des gaz d'échappement pour moteur à combustion interne WO2012157066A1 (fr)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015136262A1 (fr) * 2014-03-11 2015-09-17 Johnson Matthey Catalysts (Germany) Gmbh Système compact cylindrique de réduction catalytique sélective permettant une réduction de l'oxyde d'azote dans des gaz d'échappement riches en oxygène de moteurs à combustion interne de 500 à 4 500 kw
WO2015185297A1 (fr) * 2014-06-04 2015-12-10 Robert Bosch Gmbh Module d'injection et ligne d'échappement comprenant un module d'injection
US9616383B2 (en) 2014-02-06 2017-04-11 Johnson Matthey Catalysts (Germany) Gmbh Compact selective catalytic reduction system for nitrogen oxide reduction in the oxygen-rich exhaust of 500 to 4500 kW internal combustion engines
US10443587B2 (en) 2013-06-28 2019-10-15 Robert Bosch Gmbh High-pressure fuel pump

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003239727A (ja) * 2002-02-13 2003-08-27 Komatsu Ltd 排気ガス浄化装置
JP2009085050A (ja) * 2007-09-28 2009-04-23 Denso Corp 添加剤噴射弁、添加剤噴射装置、及び排気浄化システム
JP2010242704A (ja) * 2009-04-09 2010-10-28 Toyota Industries Corp 排気ガスの浄化装置

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003239727A (ja) * 2002-02-13 2003-08-27 Komatsu Ltd 排気ガス浄化装置
JP2009085050A (ja) * 2007-09-28 2009-04-23 Denso Corp 添加剤噴射弁、添加剤噴射装置、及び排気浄化システム
JP2010242704A (ja) * 2009-04-09 2010-10-28 Toyota Industries Corp 排気ガスの浄化装置

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10443587B2 (en) 2013-06-28 2019-10-15 Robert Bosch Gmbh High-pressure fuel pump
US9616383B2 (en) 2014-02-06 2017-04-11 Johnson Matthey Catalysts (Germany) Gmbh Compact selective catalytic reduction system for nitrogen oxide reduction in the oxygen-rich exhaust of 500 to 4500 kW internal combustion engines
WO2015136262A1 (fr) * 2014-03-11 2015-09-17 Johnson Matthey Catalysts (Germany) Gmbh Système compact cylindrique de réduction catalytique sélective permettant une réduction de l'oxyde d'azote dans des gaz d'échappement riches en oxygène de moteurs à combustion interne de 500 à 4 500 kw
CN106170613A (zh) * 2014-03-11 2016-11-30 庄信万丰催化剂(德国)有限公司 用于500kW至4500kW的内燃机的富氧排气中的氮氧化物还原的紧凑圆柱形选择性催化还原系统
US9803529B2 (en) 2014-03-11 2017-10-31 Johnson Matthey Catalysts (Germany) Gmbh Compact cylindrical selective catalytic reduction system for nitrogen oxide reduction in the oxygen-rich exhaust of 500 to 4500 kW internal combustion engines
CN106170613B (zh) * 2014-03-11 2019-04-09 庄信万丰催化剂(德国)有限公司 选择性催化还原系统及其使用方法
WO2015185297A1 (fr) * 2014-06-04 2015-12-10 Robert Bosch Gmbh Module d'injection et ligne d'échappement comprenant un module d'injection
CN106536882A (zh) * 2014-06-04 2017-03-22 罗伯特·博世有限公司 喷射模块和具有喷射模块的废气系统

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