US20160040569A1 - Exhaust gas purifying filter, system and regenerating gasoline particulate filter, and method thereof - Google Patents
Exhaust gas purifying filter, system and regenerating gasoline particulate filter, and method thereof Download PDFInfo
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- US20160040569A1 US20160040569A1 US14/886,679 US201514886679A US2016040569A1 US 20160040569 A1 US20160040569 A1 US 20160040569A1 US 201514886679 A US201514886679 A US 201514886679A US 2016040569 A1 US2016040569 A1 US 2016040569A1
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- ammonia
- particulate filter
- exhaust gas
- catalyst unit
- storage catalyst
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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
- F01N3/02—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
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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
- F01N3/02—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]
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
- F01N13/009—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series
- F01N13/0097—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series the purifying devices are arranged in a single housing
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/02—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
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
- F01N3/0814—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents combined with catalytic converters, e.g. NOx absorption/storage reduction catalysts
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/101—Three-way catalysts
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
- F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
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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]
- F01N3/2073—Selective catalytic reduction [SCR] with means for generating a reducing substance from the exhaust gases
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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
- F01N2370/00—Selection of materials for exhaust purification
- F01N2370/02—Selection of materials for exhaust purification used in catalytic reactors
- F01N2370/04—Zeolitic material
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2430/00—Influencing exhaust purification, e.g. starting of catalytic reaction, filter regeneration, or the like, by controlling engine operating characteristics
- F01N2430/06—Influencing exhaust purification, e.g. starting of catalytic reaction, filter regeneration, or the like, by controlling engine operating characteristics by varying fuel-air ratio, e.g. by enriching fuel-air mixture
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2570/00—Exhaust treating apparatus eliminating, absorbing or adsorbing specific elements or compounds
- F01N2570/18—Ammonia
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/021—Introducing corrections for particular conditions exterior to the engine
- F02D41/0235—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus
- F02D41/027—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to purge or regenerate the exhaust gas treating apparatus
- F02D41/029—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to purge or regenerate the exhaust gas treating apparatus the exhaust gas treating apparatus being a particulate filter
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Definitions
- the present invention relates to an exhaust gas purifying filter, a system for regenerating a particulate filter, and a method thereof. More particularly, the present invention relates to an exhaust gas purifying filter, and a system and a method for regenerating a particulate filter of a gasoline engine.
- GDI gasoline direct injection
- GDI gasoline direct injection engine
- the present invention has been made in an effort to provide an exhaust gas purifying filter, and a system and a method for regenerating a particulate filter having advantages of sufficiently oxidizing particulate matter in a particulate filter of a gasoline engine.
- the present invention has been made in an effort to provide an exhaust gas purifying filter, and a system and a method for regenerating a particulate filter having further advantages of oxidizing the particulate matter in the particulate filter of a gasoline engine at a lower temperature than typically required.
- the present invention provides an exhaust gas purifying filter that includes: an ammonia storage catalyst unit adapted to absorb ammonia contained in the exhaust gas when a temperature of the ammonia storage catalyst unit is lower than a predetermined temperature, release the absorbed ammonia when the temperature of the ammonia storage catalyst unit is higher than or equal to the predetermined temperature, and generate nitrogen oxide from the released ammonia; and a particulate filter adapted to trap particulate matter contained in the exhaust gas and regenerate the trapped particulate matter by using the nitrogen oxide generated by the ammonia storage catalyst unit.
- the ammonia storage catalyst unit may further include a three-way catalyst layer.
- the ammonia storage catalyst unit may include zeolite or an ammonia absorptive material.
- a system for regenerating a particulate filter, wherein the system may be mounted on an exhaust pipe of a gasoline engine.
- the system may include: a three-way catalyst device mounted on the exhaust pipe connected to the gasoline engine, the three-way catalyst device adapted to oxidize or reduce an exhaust gas exhausted from the gasoline engine; an ammonia storage catalyst unit mounted on the exhaust pipe downstream of the three-way catalyst device, wherein the ammonia storage catalyst unit is adapted to absorb ammonia generated in the three-way catalyst when a temperature of the ammonia storage catalyst unit is lower than a predetermined temperature, release the absorbed ammonia when the temperature of the ammonia storage catalyst unit is higher than or equal to the predetermined temperature, and generate nitrogen oxide from the released ammonia; a particulate filter mounted proximal to the ammonia storage catalyst unit, and adapted to trap particulate matter contained in the exhaust gas and regenerate the trapped particulate matter by using the nitrogen oxide generated from the ammonia storage
- control portion is adapted to create a rich atmosphere when a concentration of the ammonia is lower than or equal to a predetermined concentration.
- control portion is adapted to create a lean atmosphere depending on the temperature of the ammonia storage catalyst unit when the pressure difference of the particulate filter is larger than or equal to the predetermined pressure difference.
- the ammonia storage catalyst unit further includes a three-way catalyst layer.
- the ammonia storage catalyst unit includes zeolite or an ammonia absorptive material.
- a system for regenerating a particulate filter which can be applied to the present methods for regenerating a particulate filter.
- the method may include: absorbing the ammonia contained in the exhaust gas; comparing a pressure difference of the particulate filter to a predetermined pressure difference; creating a lean atmosphere when the pressure difference of the particulate filter is larger than or equal to the predetermined pressure difference; releasing the ammonia from the ammonia storage catalyst unit; generating nitrogen oxide from the released ammonia; and regenerating the particulate filter using the generated nitrogen oxide.
- generating the nitrogen oxide is performed by creating a lean atmosphere depending on the temperature of the ammonia storage catalyst unit.
- a ratio of the ammonia in the exhaust gas is raised by creating a rich atmosphere when the ammonia is absorbed.
- vehicle or “vehicular” or other similar term as used herein is inclusive of motor vehicles in general such as passenger automobiles including sports utility vehicles (SUV), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like, and includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles and other alternative fuel vehicles (e.g., fuels derived from resources other than petroleum).
- a hybrid vehicle is a vehicle that has two or more sources of power, for example both gasoline-powered and electric-powered vehicles.
- FIG. 1 and FIG. 2 are schematic diagrams of a system for purifying an exhaust gas according to an exemplary embodiment of the present invention.
- FIG. 3 is a graph showing an absorption ratio of ammonia according to temperature change.
- FIG. 4 is a flowchart of a method for purifying exhaust gas according to an exemplary embodiment of the present invention.
- FIG. 5 is a graph showing a combustion ratio according to temperature change of particulate matter.
- FIG. 1 and FIG. 2 are schematic diagrams of a system for purifying exhaust gas according to an exemplary embodiment of the present invention
- FIG. 3 is a graph showing an absorption ratio of ammonia according to temperature change.
- a system 1 for regenerating a particulate filter includes a gasoline engine 10 , a three-way catalyst device 20 , an ammonia storage catalyst unit 32 , a particulate filter 35 , and a control portion 40 .
- the gasoline engine 10 is an internal combustion engine using gasoline as a fuel, and burns fuel and air so as to convert chemical energy into mechanical energy.
- the gasoline engine 10 includes a plurality of cylinders 11 into which the fuel and the air flow, and an ignition device (not shown) for igniting the fuel and the air flowing into the cylinders 11 .
- the gasoline engine 10 is connected to an intake manifold 15 so as to receive the air in the cylinders 11 , and is connected to an exhaust manifold 17 such that exhaust gas generated in a combustion process is gathered in the exhaust manifold 17 and is exhausted to the exterior through an exhaust pipe 19 .
- an injector 13 can be mounted at the cylinders 11 so as to inject the fuel into the cylinders 11 .
- the three-way catalyst device 20 is mounted on the exhaust pipe 19 , and is adapted to oxidize or reduce the exhaust gas exhausted from the gasoline engine 10 .
- the three-way catalyst device 20 converts toxic chemicals (CO, HC, and NO X ) in the exhaust gas into harmless gases (CO 2 , H 2 O, N 2 , and O 2 ) by way of an oxidation-reduction reaction.
- the three-way catalyst device 20 is a catalytic converter that stimulates the oxidation-reduction reaction, and generally includes a suitable catalyst, such as, for example, a combination of platinum (Pt), palladium (Pd), and rhodium (Rh).
- a suitable catalyst such as, for example, a combination of platinum (Pt), palladium (Pd), and rhodium (Rh).
- the platinum catalyst and the palladium catalyst stimulate the oxidation reaction to reduce carbon monoxide (CO) and hydrocarbon (HC), and the rhodium catalyst stimulates the reduction reaction to reduce nitrogen oxide (NO X ).
- the air-fuel ratio is lean (i.e., air is rich as compared to fuel)
- the oxidation reaction for reducing carbon monoxide (CO) and hydrocarbon (HC) occurs actively in the three-way catalyst device 20 such that production ratios of water (H 2 O) and carbon dioxide (CO 2 ) are increased.
- the air-fuel ratio is rich (i.e., air is lean as compared to fuel)
- the reduction reaction for reducing nitrogen oxide (NO x ) actively occurs such that a production ratio of nitrogen N 2 is increased.
- the ammonia storage catalyst unit 32 is mounted on the exhaust pipe 19 downstream of the three-way catalyst device 20 .
- the ammonia storage catalyst unit 32 can, for example, be mounted in the proximity of the particulate filter 35 , or can be mounted in the particulate filter 35 .
- the ammonia storage catalyst unit 32 and the particulate filter 35 can be provided in a common space.
- the ammonia storage catalyst unit 32 is adapted to absorb and release ammonia (NH 3 ). As described above, if an excessive amount of fuel is supplied, ammonia (NH 3 ) is produced by reducing nitrogen oxide (NO X ) in the three-way catalyst device 20 . Therefore, the ammonia storage catalyst unit 32 is adapted to mainly absorb and release ammonia (NH 3 ) produced in the three-way catalyst device 20 .
- an absorption ratio and a release ratio of ammonia (NH 3 ) in the ammonia storage catalyst unit 32 vary according to temperature. That is, the lower the temperature is, the higher the absorption ratio of ammonia (NH 3 ) in the ammonia storage catalyst unit 32 . On the contrary, the higher the temperature is, the higher the release ratio of ammonia (NH 3 ) in the ammonia storage catalyst unit 32 . Therefore, as shown in FIG. 3 , ammonia (NH 3 ) produced in the three-way catalyst device 20 is mainly absorbed below a certain temperature of the ammonia storage catalyst unit 32 and is mainly released at a temperature higher than or equal to the certain temperature of the ammonia storage catalyst unit 32 .
- the certain temperature may be, but is not limited to, about 350° C.
- this certain temperature can vary and can be, for example, about 300° C., about 310° C., about 320° C., about 330° C., about 340° C., about 360° C., about 370° C., about 380° C., etc.
- the ammonia storage catalyst unit 32 can include, in addition to the ammonia storage layer 33 , a three-way catalyst layer 34 .
- one of the ammonia storage layer 33 or the three-way catalyst layer 34 is provided on the other (i.e. the three-way catalyst layer 34 or the ammonia storage layer 33 respectively) in the ammonia storage catalyst unit 32 .
- the three-way catalyst layer 34 is disposed on the ammonia storage layer 33 , but such disposition of the three-way catalyst layer 34 and the ammonia storage layer 33 are not limited as such.
- the three-way catalyst layer 34 and the three-way catalyst device 20 are provided separated from each other.
- the three-way catalyst layer 34 like the three-way catalyst device 20 , is adapted to oxidize or reduce exhaust gas.
- the three-way catalyst layer 34 produces ammonia (NH 3 ) by reducing nitrogen oxide (NO x ) which is not reduced in the three-way catalyst device 20 . Therefore, an ammonia (NH 3 ) ratio in the exhaust gas passing to the ammonia storage layer 33 is increased.
- the three-way catalyst layer 34 increases the production ratio of nitrogen oxide (NO x ), particularly nitrogen dioxide (NO 2 ), particularly by stimulating the oxidation reaction of ammonia (NH 3 ) released from the ammonia storage layer 33 .
- the particulate filter 35 is mounted downstream in the proximity of the ammonia storage catalyst unit 32 , and is adapted to trap particulate matter (PM) in the exhaust gas.
- the particulate matter (PM) mainly comprises hydrocarbon that is called soot, a soluble organic fraction, and so on.
- the particulate filter 35 is adapted to trap the particulate matter (PM).
- the particulate filter 35 has a honeycomb structure.
- the particulate filter 35 is configured to perform a regeneration process to oxidize and eliminate the particulate matter (PM).
- a pressure difference is created in the particulate filter 35 .
- a pressure sensor 38 is configured and arranged to measure this pressure difference. If the pressure difference measured by the differential pressure sensor 38 is higher than or equal to a predetermined pressure difference, then the particulate filter 35 performs a regeneration process.
- the particulate filter 35 is adapted to regenerate the particulate matter (PM) using the nitrogen oxide (NO x ), particularly nitrogen dioxide (NO 2 ), which is generated by oxidizing the ammonia (NH 3 ) released from the ammonia storage catalyst unit 32 . That is, the particulate matter (PM) is oxidized and eliminated by an oxidation reaction with the nitrogen oxide (NO x ), particularly nitrogen dioxide (NO 2 ).
- a control portion 40 is provided which is adapted to control an air-fuel ratio of an air-fuel mixture flowing into the gasoline engine 10 .
- the control portion 40 is adapted to control the fuel amount and the air amount flowing into the gasoline engine 10 so as to control the oxygen (O 2 ) ratio in the exhaust gas.
- the control portion 40 receives the pressure difference value measured by the differential pressure sensor 38 , compares the measured pressure difference value with a predetermined pressure difference value, and determines whether the particulate filter 35 will be regenerated. If the pressure difference of the particulate filter 35 is larger than or equal to the predetermined pressure difference, then the control portion 40 is adapted to create a lean atmosphere. In particular, the control portion 40 is adapted to increase the oxygen (O 2 ) ratio in the exhaust gas so as to oxidize and eliminate the particulate matter (PM), mainly carbon (C) particles, from the particulate filter 35 . According to an exemplary embodiment, the control portion 40 is adapted to control the injector 13 and can, for example, stop the supply of fuel into the cylinder 11 so as to increase the oxygen (O 2 ) ratio in the exhaust gas.
- the present system is configured such that when controlling the air-fuel ratio to be lean for regeneration of the particulate filter 35 , the control portion 40 is adapted to further control the air-fuel ratio depending to the temperature of the ammonia storage catalyst unit 32 as measured by a temperature sensor 36 .
- the control portion 40 is adapted to control the air-fuel ratio by comparing the temperature measured in the temperature sensor 36 with a releasable temperature (e.g., about 350° C.) in the ammonia storage catalyst unit 32 .
- This releasable temperature is a temperature at which the ammonia (NH 3 ) can be released in the ammonia storage catalyst unit 32 .
- control portion 40 is adapted to increase the oxygen (O 2 ) ratio in the exhaust gas so as to increase the measured temperature to the releasable temperature of the ammonia storage catalyst unit 32 .
- the control portion 40 is further adapted to control the ammonia (NH 3 ) ratio in the exhaust gas.
- the control portion 40 can receive the ammonia (NH 3 ) concentration value as measured by an ammonia concentration measure sensor (not shown), and compare the measured ammonia (NH 3 ) concentration with a predetermined concentration. If the measured ammonia (NH 3 ) concentration is lower than the predetermined concentration, then the control portion 40 can be adapted to create a rich atmosphere.
- the control portion 40 is adapted to control the injector 13 and supply the fuel in an excessive amount to the cylinder 11 so as to increase the ammonia (NH 3 ) ratio in the exhaust gas.
- the control portion 40 can further be configured to calculate the ammonia (NH 3 ) ratio in the exhaust gas depending on parameters (e.g., an engine operation condition, an exhaust gas temperature, an air-fuel ratio, a degradation amount of the catalyst, and so an), and the control portion 40 can include a map table in which the ammonia (NH 3 ) ratio according to the parameters is stored in advance.
- parameters e.g., an engine operation condition, an exhaust gas temperature, an air-fuel ratio, a degradation amount of the catalyst, and so an
- FIG. 4 is a flowchart showing a method for purifying exhaust gas according to an exemplary embodiment of the present invention.
- FIG. 4 a regenerating method using the system 1 as shown in FIGS. 1 and 2 will be described in detail.
- the system 1 for regenerating the particulate filter is operated while the engine operates beginning at step S 100 .
- step S 110 the fuel is supplied excessively into the gasoline engine 10
- step S 110 the fuel is supplied excessively into the gasoline engine 10
- step S 120 the reduction reaction of the nitrogen oxide (NOx) is stimulated in the three-way catalyst device 20 and the ammonia (NH 3 ) is produced at step S 120 .
- the fuel is supplied excessively for protecting the exhaust manifold 17 and the catalyst of the three-way catalyst device 20 .
- the control portion 40 is adapted to control the injector 13 so as to supply the fuel excessively.
- the ammonia NH 3 of the exhaust gas exhausted in the three-way catalyst device 20 is then absorbed in the ammonia storage catalyst unit 32 at step S 130 .
- the ammonia (NH 3 ) is absorbed below the certain temperature, (e.g., about 350° C.) in the ammonia storage catalyst unit 32 . Because the temperature of the exhaust gas is not higher than the releasable temperature during a normal operating mode of the gasoline engine 10 , a majority of the ammonia (NH 3 ) is absorbed in the ammonia storage catalyst unit 32 .
- the differential pressure sensor 38 measures the pressure difference of the particulate filter 35 during the normal operating mode of the gasoline engine 10 at step S 140 , and transmits the measured pressure difference to the control portion 40 .
- the control portion 40 determines whether the pressure difference of the particulate filter 35 is larger than or equal to the predetermined pressure difference at step S 150 . If the pressure difference of the particulate filter 35 is larger than or equal to the predetermined pressure difference, the control portion 40 is adapted to control the air-fuel ratio in the gasoline engine 10 to be lean at step S 160 . Since the oxygen (O 2 ) ratio in the exhaust gas exhausted from the gasoline engine 10 is increased, the oxidation reaction in the three-way catalyst device 20 is stimulated, thereby increasing the temperature of the exhaust gas by the generated oxidation heat.
- ammonia (NH 3 ) is released from the ammonia storage layer 33 of the ammonia storage catalyst unit 32 at step S 170 .
- the released ammonia (NH 3 ) is oxidized such that the nitrogen oxide (NO x ), particularly nitrogen dioxide (NO 2 ), is generated at step S 180 .
- the particulate matter (PM) in the particulate filter 35 is oxidized and eliminated by the nitrogen oxide (NOx), particularly nitrogen dioxide (NO 2 ), at step S 190 . That is, the particulate filter 35 is regenerated.
- the particulate filter 35 is adapted to oxidize and eliminate the particulate matter (PM) using oxygen (O 2 ) gas, but the system 1 for regenerating the particulate filter may also be adapted to oxidize and eliminate the particulate matter (PM) using nitrogen dioxide (NO 2 ).
- FIG. 5 is a graph for showing a combustion ratio according to temperature change of particulate matter.
- an ambient temperature must be higher than or equal to about 400° C. at a minimum for oxidizing (i.e., burning) the particulate matter (PM) (e.g. soot) trapped in the particulate filter with oxygen (O 2 ) gas.
- oxygen oxygen
- nitrogen dioxide NO 2
- the system 1 for regenerating the particulate filter is adapted to increase nitrogen dioxide (NO 2 ) flowing into the particulate filter 35 such that the particulate matter (PM) is oxidized and eliminated by the nitrogen dioxide (NO 2 ) at a lower temperature when the particulate filter 35 is to be regenerated.
- the particulate matter (PM) in the particulate filter 35 of the gasoline engine may be sufficiently oxidized according to exemplary embodiments of the present invention.
- the particulate matter (PM) in the particulate filter 35 of the gasoline engine may be oxidized at a temperature lower than typically required.
Abstract
An exhaust gas purifying filter, a system for regenerating a particulate filter, and a method therefore are disclosed. An exhaust gas purifying filter may include: an ammonia storage catalyst unit adapted to absorb ammonia contained in the exhaust gas when a temperature of the ammonia storage catalyst unit is lower than a predetermined temperature, release the absorbed ammonia when the temperature of the ammonia storage catalyst unit is higher than or equal to the predetermined temperature, and generate nitrogen oxide from the released ammonia; and a particulate filter adapted to trap particulate matter contained in the exhaust gas and regenerate the trapped particulate matter by using the nitrogen oxide generated from the ammonia storage catalyst unit.
Description
- This application claims priority to and the benefit of Korean Patent Application No. 10-2011-0104662 filed in the Korean Intellectual Property Office on Oct. 13, 2011, the entire contents of which are incorporated herein by reference.
- (a) Field of the Invention
- The present invention relates to an exhaust gas purifying filter, a system for regenerating a particulate filter, and a method thereof. More particularly, the present invention relates to an exhaust gas purifying filter, and a system and a method for regenerating a particulate filter of a gasoline engine.
- (b) Description of the Related Art
- In general, a gasoline direct injection (GDI) technology involves direct injection of fuel into a combustion chamber as opposed to injection into an intake pipe. The technology has been developed so as to improve fuel consumption efficiency and performance of an internal combustion engine.
- Since the air/fuel ratio is low (rich atmosphere) around a spark plug, an engine generally is operated in a lean fuel condition. However, this presents a problem in a gasoline direct injection engine (GDI) which generates a large amount of particulate matter (PM) during an incomplete combustion period increment in a combustion chamber. Accordingly, a particulate filter is mounted in a vehicle with a gasoline direct injection engine (GDI).
- However, if such a vehicle operates at a low speed for a long time, it is difficult to passively regenerate particulate matter (PM) in the particulate filter because the temperature and oxygen concentration in the particulate filter are low.
- In a conventional art, various devices for supplying oxygen to a particulate filter have been developed in an attempt to resolve such problems. In particular, regeneration of the particulate filter has been performed such that the particle matter (PM) trapped in the particulate filter is oxidized and eliminated by supplying additional air to the front end of the particulate filter mounted on an exhaust pipe.
- Although the additional air is supplied to the front end of the particulate filter, a high temperature is required for oxidizing PM trapped in the particulate filter with oxygen. However, in the particulate filter of a gasoline engine, it is difficult to secure a temperature at which the particle matter (PM) and the oxygen can sufficiently react.
- The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
- The present invention has been made in an effort to provide an exhaust gas purifying filter, and a system and a method for regenerating a particulate filter having advantages of sufficiently oxidizing particulate matter in a particulate filter of a gasoline engine.
- In addition, the present invention has been made in an effort to provide an exhaust gas purifying filter, and a system and a method for regenerating a particulate filter having further advantages of oxidizing the particulate matter in the particulate filter of a gasoline engine at a lower temperature than typically required.
- According to one aspect, the present invention provides an exhaust gas purifying filter that includes: an ammonia storage catalyst unit adapted to absorb ammonia contained in the exhaust gas when a temperature of the ammonia storage catalyst unit is lower than a predetermined temperature, release the absorbed ammonia when the temperature of the ammonia storage catalyst unit is higher than or equal to the predetermined temperature, and generate nitrogen oxide from the released ammonia; and a particulate filter adapted to trap particulate matter contained in the exhaust gas and regenerate the trapped particulate matter by using the nitrogen oxide generated by the ammonia storage catalyst unit.
- According to various embodiments, the ammonia storage catalyst unit may further include a three-way catalyst layer.
- According to various embodiments, the ammonia storage catalyst unit may include zeolite or an ammonia absorptive material.
- According to another aspect of the present invention, a system is provided for regenerating a particulate filter, wherein the system may be mounted on an exhaust pipe of a gasoline engine. According to various embodiments, the system may include: a three-way catalyst device mounted on the exhaust pipe connected to the gasoline engine, the three-way catalyst device adapted to oxidize or reduce an exhaust gas exhausted from the gasoline engine; an ammonia storage catalyst unit mounted on the exhaust pipe downstream of the three-way catalyst device, wherein the ammonia storage catalyst unit is adapted to absorb ammonia generated in the three-way catalyst when a temperature of the ammonia storage catalyst unit is lower than a predetermined temperature, release the absorbed ammonia when the temperature of the ammonia storage catalyst unit is higher than or equal to the predetermined temperature, and generate nitrogen oxide from the released ammonia; a particulate filter mounted proximal to the ammonia storage catalyst unit, and adapted to trap particulate matter contained in the exhaust gas and regenerate the trapped particulate matter by using the nitrogen oxide generated from the ammonia storage catalyst unit; and a control portion adapted to control an air-fuel ratio of an air-fuel mixture flowing into the gasoline engine, wherein the control portion is further adapted to create a lean atmosphere when a pressure difference of the particulate filter is larger than or equal to a predetermined pressure difference. In particular, when used herein, creating a lean atmosphere refers to creating an atmosphere in which the air/fuel ratio is high (as opposed to a rich atmosphere in which the air/fuel ratio is low).
- According to various embodiments, the control portion is adapted to create a rich atmosphere when a concentration of the ammonia is lower than or equal to a predetermined concentration.
- According to various embodiments, the control portion is adapted to create a lean atmosphere depending on the temperature of the ammonia storage catalyst unit when the pressure difference of the particulate filter is larger than or equal to the predetermined pressure difference.
- According to various embodiments, the ammonia storage catalyst unit further includes a three-way catalyst layer.
- According to various embodiments, the ammonia storage catalyst unit includes zeolite or an ammonia absorptive material.
- According to another aspect of the present invention, a system for regenerating a particulate filter is provided which can be applied to the present methods for regenerating a particulate filter. According to various embodiments, the method may include: absorbing the ammonia contained in the exhaust gas; comparing a pressure difference of the particulate filter to a predetermined pressure difference; creating a lean atmosphere when the pressure difference of the particulate filter is larger than or equal to the predetermined pressure difference; releasing the ammonia from the ammonia storage catalyst unit; generating nitrogen oxide from the released ammonia; and regenerating the particulate filter using the generated nitrogen oxide.
- According to various embodiments, generating the nitrogen oxide is performed by creating a lean atmosphere depending on the temperature of the ammonia storage catalyst unit.
- According to various embodiments, a ratio of the ammonia in the exhaust gas is raised by creating a rich atmosphere when the ammonia is absorbed.
- It is understood that the term “vehicle” or “vehicular” or other similar term as used herein is inclusive of motor vehicles in general such as passenger automobiles including sports utility vehicles (SUV), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like, and includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles and other alternative fuel vehicles (e.g., fuels derived from resources other than petroleum). As referred to herein, a hybrid vehicle is a vehicle that has two or more sources of power, for example both gasoline-powered and electric-powered vehicles.
-
FIG. 1 andFIG. 2 are schematic diagrams of a system for purifying an exhaust gas according to an exemplary embodiment of the present invention. -
FIG. 3 is a graph showing an absorption ratio of ammonia according to temperature change. -
FIG. 4 is a flowchart of a method for purifying exhaust gas according to an exemplary embodiment of the present invention. -
FIG. 5 is a graph showing a combustion ratio according to temperature change of particulate matter. -
-
<Description of Symbols> 1: system for regenerating particulate filter 10: gasoline engine 11: cylinder 13: injector 15: intake manifold 17: exhaust manifold 19: exhaust pipe 20: three-way catalyst device 32: ammonia storage catalyst unit 33: ammonia storage layer 34: three-way catalyst layer 35: particulate filter 36: temperature sensor 38: differential pressure sensor 40: control portion - An exemplary embodiment of the present invention will hereinafter be described in detail with reference to the accompanying drawings.
-
FIG. 1 andFIG. 2 are schematic diagrams of a system for purifying exhaust gas according to an exemplary embodiment of the present invention, andFIG. 3 is a graph showing an absorption ratio of ammonia according to temperature change. - Referring to
FIG. 1 andFIG. 2 , asystem 1 for regenerating a particulate filter according to an exemplary embodiment of the present invention includes agasoline engine 10, a three-way catalyst device 20, an ammoniastorage catalyst unit 32, aparticulate filter 35, and acontrol portion 40. - The
gasoline engine 10 is an internal combustion engine using gasoline as a fuel, and burns fuel and air so as to convert chemical energy into mechanical energy. Thegasoline engine 10 includes a plurality ofcylinders 11 into which the fuel and the air flow, and an ignition device (not shown) for igniting the fuel and the air flowing into thecylinders 11. Thegasoline engine 10 is connected to anintake manifold 15 so as to receive the air in thecylinders 11, and is connected to anexhaust manifold 17 such that exhaust gas generated in a combustion process is gathered in theexhaust manifold 17 and is exhausted to the exterior through anexhaust pipe 19. As further shown, aninjector 13 can be mounted at thecylinders 11 so as to inject the fuel into thecylinders 11. - The three-
way catalyst device 20 is mounted on theexhaust pipe 19, and is adapted to oxidize or reduce the exhaust gas exhausted from thegasoline engine 10. Generally, the three-way catalyst device 20 converts toxic chemicals (CO, HC, and NOX) in the exhaust gas into harmless gases (CO2, H2O, N2, and O2) by way of an oxidation-reduction reaction. - The three-
way catalyst device 20 is a catalytic converter that stimulates the oxidation-reduction reaction, and generally includes a suitable catalyst, such as, for example, a combination of platinum (Pt), palladium (Pd), and rhodium (Rh). The platinum catalyst and the palladium catalyst stimulate the oxidation reaction to reduce carbon monoxide (CO) and hydrocarbon (HC), and the rhodium catalyst stimulates the reduction reaction to reduce nitrogen oxide (NOX). If the air-fuel ratio is lean (i.e., air is rich as compared to fuel), the oxidation reaction for reducing carbon monoxide (CO) and hydrocarbon (HC) occurs actively in the three-way catalyst device 20 such that production ratios of water (H2O) and carbon dioxide (CO2) are increased. On the other and, if the air-fuel ratio is rich (i.e., air is lean as compared to fuel), the reduction reaction for reducing nitrogen oxide (NOx) actively occurs such that a production ratio of nitrogen N2 is increased. - As shown in
FIGS. 1 and 2 , the ammoniastorage catalyst unit 32 is mounted on theexhaust pipe 19 downstream of the three-way catalyst device 20. The ammoniastorage catalyst unit 32 can, for example, be mounted in the proximity of theparticulate filter 35, or can be mounted in theparticulate filter 35. As shown inFIG. 1 andFIG. 2 , the ammoniastorage catalyst unit 32 and theparticulate filter 35 can be provided in a common space. - The ammonia
storage catalyst unit 32 is adapted to absorb and release ammonia (NH3). As described above, if an excessive amount of fuel is supplied, ammonia (NH3) is produced by reducing nitrogen oxide (NOX) in the three-way catalyst device 20. Therefore, the ammoniastorage catalyst unit 32 is adapted to mainly absorb and release ammonia (NH3) produced in the three-way catalyst device 20. - In the present system, an absorption ratio and a release ratio of ammonia (NH3) in the ammonia
storage catalyst unit 32 vary according to temperature. That is, the lower the temperature is, the higher the absorption ratio of ammonia (NH3) in the ammoniastorage catalyst unit 32. On the contrary, the higher the temperature is, the higher the release ratio of ammonia (NH3) in the ammoniastorage catalyst unit 32. Therefore, as shown inFIG. 3 , ammonia (NH3) produced in the three-way catalyst device 20 is mainly absorbed below a certain temperature of the ammoniastorage catalyst unit 32 and is mainly released at a temperature higher than or equal to the certain temperature of the ammoniastorage catalyst unit 32. According to an exemplary embodiment, the certain temperature may be, but is not limited to, about 350° C. Of course, this certain temperature can vary and can be, for example, about 300° C., about 310° C., about 320° C., about 330° C., about 340° C., about 360° C., about 370° C., about 380° C., etc. - The ammonia
storage catalyst unit 32 can use various absorptive materials. According to an exemplary embodiment, one of the absorptive materials may be zeolite. - As shown in
FIG. 2 , the ammoniastorage catalyst unit 32 can include, in addition to theammonia storage layer 33, a three-way catalyst layer 34. According to an embodiment, one of theammonia storage layer 33 or the three-way catalyst layer 34 is provided on the other (i.e. the three-way catalyst layer 34 or theammonia storage layer 33 respectively) in the ammoniastorage catalyst unit 32. In particular, according to one embodiment the three-way catalyst layer 34 is disposed on theammonia storage layer 33, but such disposition of the three-way catalyst layer 34 and theammonia storage layer 33 are not limited as such. - As shown in
FIGS. 1 and 2 , the three-way catalyst layer 34 and the three-way catalyst device 20 are provided separated from each other. According to preferred embodiments, the three-way catalyst layer 34, like the three-way catalyst device 20, is adapted to oxidize or reduce exhaust gas. Thus, for example, if the fuel is supplied excessively (i.e., air-fuel ratio is rich), the three-way catalyst layer 34 produces ammonia (NH3) by reducing nitrogen oxide (NOx) which is not reduced in the three-way catalyst device 20. Therefore, an ammonia (NH3) ratio in the exhaust gas passing to theammonia storage layer 33 is increased. Also, if oxygen (O2) is supplied excessively (i.e., air-fuel ratio is lean), then the three-way catalyst layer 34 increases the production ratio of nitrogen oxide (NOx), particularly nitrogen dioxide (NO2), particularly by stimulating the oxidation reaction of ammonia (NH3) released from theammonia storage layer 33. - As shown in
FIGS. 1 and 2 , theparticulate filter 35 is mounted downstream in the proximity of the ammoniastorage catalyst unit 32, and is adapted to trap particulate matter (PM) in the exhaust gas. The particulate matter (PM) mainly comprises hydrocarbon that is called soot, a soluble organic fraction, and so on. Theparticulate filter 35 is adapted to trap the particulate matter (PM). According to a preferred embodiment, theparticulate filter 35 has a honeycomb structure. - However, if the particulate matter (PM) becomes trapped in the
particulate filter 35, the flow of the exhaust gas may be interrupted. Therefore, theparticulate filter 35 is configured to perform a regeneration process to oxidize and eliminate the particulate matter (PM). In particular, if particulate matter (PM) of more than a certain amount is trapped in theparticulate filter 35, then a pressure difference is created in theparticulate filter 35. Apressure sensor 38 is configured and arranged to measure this pressure difference. If the pressure difference measured by thedifferential pressure sensor 38 is higher than or equal to a predetermined pressure difference, then theparticulate filter 35 performs a regeneration process. - The
particulate filter 35 is adapted to regenerate the particulate matter (PM) using the nitrogen oxide (NOx), particularly nitrogen dioxide (NO2), which is generated by oxidizing the ammonia (NH3) released from the ammoniastorage catalyst unit 32. That is, the particulate matter (PM) is oxidized and eliminated by an oxidation reaction with the nitrogen oxide (NOx), particularly nitrogen dioxide (NO2). - As shown in
FIGS. 1 and 2 , acontrol portion 40 is provided which is adapted to control an air-fuel ratio of an air-fuel mixture flowing into thegasoline engine 10. In particular, thecontrol portion 40 is adapted to control the fuel amount and the air amount flowing into thegasoline engine 10 so as to control the oxygen (O2) ratio in the exhaust gas. - The
control portion 40 receives the pressure difference value measured by thedifferential pressure sensor 38, compares the measured pressure difference value with a predetermined pressure difference value, and determines whether theparticulate filter 35 will be regenerated. If the pressure difference of theparticulate filter 35 is larger than or equal to the predetermined pressure difference, then thecontrol portion 40 is adapted to create a lean atmosphere. In particular, thecontrol portion 40 is adapted to increase the oxygen (O2) ratio in the exhaust gas so as to oxidize and eliminate the particulate matter (PM), mainly carbon (C) particles, from theparticulate filter 35. According to an exemplary embodiment, thecontrol portion 40 is adapted to control theinjector 13 and can, for example, stop the supply of fuel into thecylinder 11 so as to increase the oxygen (O2) ratio in the exhaust gas. - Further, the present system is configured such that when controlling the air-fuel ratio to be lean for regeneration of the
particulate filter 35, thecontrol portion 40 is adapted to further control the air-fuel ratio depending to the temperature of the ammoniastorage catalyst unit 32 as measured by atemperature sensor 36. In particular, after determining whether theparticulate filter 35 will be regenerated, thecontrol portion 40 is adapted to control the air-fuel ratio by comparing the temperature measured in thetemperature sensor 36 with a releasable temperature (e.g., about 350° C.) in the ammoniastorage catalyst unit 32. This releasable temperature is a temperature at which the ammonia (NH3) can be released in the ammoniastorage catalyst unit 32. For example, if the temperature measured in thetemperature sensor 36 is lower than the releasable temperature in the ammoniastorage catalyst unit 32, then thecontrol portion 40 is adapted to increase the oxygen (O2) ratio in the exhaust gas so as to increase the measured temperature to the releasable temperature of the ammoniastorage catalyst unit 32. - The
control portion 40 is further adapted to control the ammonia (NH3) ratio in the exhaust gas. For example, thecontrol portion 40 can receive the ammonia (NH3) concentration value as measured by an ammonia concentration measure sensor (not shown), and compare the measured ammonia (NH3) concentration with a predetermined concentration. If the measured ammonia (NH3) concentration is lower than the predetermined concentration, then thecontrol portion 40 can be adapted to create a rich atmosphere. In particular, thecontrol portion 40 is adapted to control theinjector 13 and supply the fuel in an excessive amount to thecylinder 11 so as to increase the ammonia (NH3) ratio in the exhaust gas. - The
control portion 40 can further be configured to calculate the ammonia (NH3) ratio in the exhaust gas depending on parameters (e.g., an engine operation condition, an exhaust gas temperature, an air-fuel ratio, a degradation amount of the catalyst, and so an), and thecontrol portion 40 can include a map table in which the ammonia (NH3) ratio according to the parameters is stored in advance. -
FIG. 4 is a flowchart showing a method for purifying exhaust gas according to an exemplary embodiment of the present invention. - Referring to
FIG. 4 , a regenerating method using thesystem 1 as shown inFIGS. 1 and 2 will be described in detail. - Referring to
FIG. 4 , thesystem 1 for regenerating the particulate filter is operated while the engine operates beginning at step S100. If thegasoline engine 10 is operated and the fuel is supplied excessively into the gasoline engine 10 (step S110) (i.e. if the air-fuel ratio is rich), then the reduction reaction of the nitrogen oxide (NOx) is stimulated in the three-way catalyst device 20 and the ammonia (NH3) is produced at step S120. Typically, in an initial operation region and at a high load region, the fuel is supplied excessively for protecting theexhaust manifold 17 and the catalyst of the three-way catalyst device 20. Also, if the ammonia (NH3) concentration as measured by the ammonia concentration measure sensor (not shown) or as calculated by thecontrol portion 40 is lower than the predetermined concentration, then thecontrol portion 40 is adapted to control theinjector 13 so as to supply the fuel excessively. The ammonia NH3 of the exhaust gas exhausted in the three-way catalyst device 20 is then absorbed in the ammoniastorage catalyst unit 32 at step S130. As described above, the ammonia (NH3) is absorbed below the certain temperature, (e.g., about 350° C.) in the ammoniastorage catalyst unit 32. Because the temperature of the exhaust gas is not higher than the releasable temperature during a normal operating mode of thegasoline engine 10, a majority of the ammonia (NH3) is absorbed in the ammoniastorage catalyst unit 32. - The
differential pressure sensor 38 measures the pressure difference of theparticulate filter 35 during the normal operating mode of thegasoline engine 10 at step S140, and transmits the measured pressure difference to thecontrol portion 40. - Then, the
control portion 40 determines whether the pressure difference of theparticulate filter 35 is larger than or equal to the predetermined pressure difference at step S150. If the pressure difference of theparticulate filter 35 is larger than or equal to the predetermined pressure difference, thecontrol portion 40 is adapted to control the air-fuel ratio in thegasoline engine 10 to be lean at step S160. Since the oxygen (O2) ratio in the exhaust gas exhausted from thegasoline engine 10 is increased, the oxidation reaction in the three-way catalyst device 20 is stimulated, thereby increasing the temperature of the exhaust gas by the generated oxidation heat. Therefore, if the increased temperature of the exhaust gas is higher than or equal to the certain temperature (e.g., about 350° C.), then ammonia (NH3) is released from theammonia storage layer 33 of the ammoniastorage catalyst unit 32 at step S170. Next, the released ammonia (NH3) is oxidized such that the nitrogen oxide (NOx), particularly nitrogen dioxide (NO2), is generated at step S180. Then the particulate matter (PM) in theparticulate filter 35 is oxidized and eliminated by the nitrogen oxide (NOx), particularly nitrogen dioxide (NO2), at step S190. That is, theparticulate filter 35 is regenerated. - Generally, the
particulate filter 35 is adapted to oxidize and eliminate the particulate matter (PM) using oxygen (O2) gas, but thesystem 1 for regenerating the particulate filter may also be adapted to oxidize and eliminate the particulate matter (PM) using nitrogen dioxide (NO2). -
FIG. 5 is a graph for showing a combustion ratio according to temperature change of particulate matter. - Referring to
FIG. 5 , an ambient temperature must be higher than or equal to about 400° C. at a minimum for oxidizing (i.e., burning) the particulate matter (PM) (e.g. soot) trapped in the particulate filter with oxygen (O2) gas. However, as shown, nitrogen dioxide (NO2) can oxidize (i.e., burn) the particulate matter (PM) below 400° C. - Therefore, the
system 1 for regenerating the particulate filter is adapted to increase nitrogen dioxide (NO2) flowing into theparticulate filter 35 such that the particulate matter (PM) is oxidized and eliminated by the nitrogen dioxide (NO2) at a lower temperature when theparticulate filter 35 is to be regenerated. - As described above, the particulate matter (PM) in the
particulate filter 35 of the gasoline engine may be sufficiently oxidized according to exemplary embodiments of the present invention. - Also, the particulate matter (PM) in the
particulate filter 35 of the gasoline engine may be oxidized at a temperature lower than typically required. - While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
Claims (4)
1.-8. (canceled)
9. A method for regenerating a particulate filter that comprises an ammonia storage catalyst unit adapted to absorb or release ammonia contained in exhaust gas depending on a temperature of the ammonia storage catalyst unit, and a particulate filter adapted to trap particulate matter contained in the exhaust gas, the method comprising:
absorbing ammonia contained in the exhaust gas;
comparing a pressure difference of the particulate filter to a predetermined pressure difference;
creating a lean atmosphere when the pressure difference of the particulate filter is larger than or equal to the predetermined pressure difference;
releasing the ammonia from the ammonia storage catalyst unit;
generating nitrogen oxide from the released ammonia; and
regenerating the particulate filter using the generated nitrogen oxide.
10. The method of claim 9 , wherein the step of generating the nitrogen oxide is performed by creating a lean atmosphere depending on the temperature of the ammonia storage catalyst unit.
11. The method of claim 9 , wherein a ratio of the ammonia in the exhaust gas is raised by creating a rich atmosphere when the ammonia is absorbed.
Priority Applications (1)
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US14/886,679 US20160040569A1 (en) | 2011-10-13 | 2015-10-19 | Exhaust gas purifying filter, system and regenerating gasoline particulate filter, and method thereof |
Applications Claiming Priority (4)
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KR10-2011-0104662 | 2011-10-13 | ||
KR1020110104662A KR101317411B1 (en) | 2011-10-13 | 2011-10-13 | System of regenerating gasoline particulate filter and method thereof |
US13/534,823 US20130095002A1 (en) | 2011-10-13 | 2012-06-27 | Exhaust gas purifying filter, system of regenerating gasoline particulate filter, and method thereof |
US14/886,679 US20160040569A1 (en) | 2011-10-13 | 2015-10-19 | Exhaust gas purifying filter, system and regenerating gasoline particulate filter, and method thereof |
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US13/534,823 Division US20130095002A1 (en) | 2011-10-13 | 2012-06-27 | Exhaust gas purifying filter, system of regenerating gasoline particulate filter, and method thereof |
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US20160040569A1 true US20160040569A1 (en) | 2016-02-11 |
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US14/886,679 Abandoned US20160040569A1 (en) | 2011-10-13 | 2015-10-19 | Exhaust gas purifying filter, system and regenerating gasoline particulate filter, and method thereof |
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US13/534,823 Abandoned US20130095002A1 (en) | 2011-10-13 | 2012-06-27 | Exhaust gas purifying filter, system of regenerating gasoline particulate filter, and method thereof |
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JP (1) | JP6054057B2 (en) |
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Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8919099B2 (en) * | 2011-06-10 | 2014-12-30 | GM Global Technology Operations LLC | System and method for determining an ammonia generation rate in a three-way catalyst |
US9714625B2 (en) | 2011-07-28 | 2017-07-25 | GM Global Technology Operations LLC | System and method for controlling ammonia levels in a selective catalytic reduction catalyst using a nitrogen oxide sensor |
US9188071B2 (en) | 2012-05-15 | 2015-11-17 | GM Global Technology Operations LLC | System and method for controlling an engine based on ammonia storage in multiple selective catalytic reduction catalysts |
JP2014073693A (en) * | 2012-10-02 | 2014-04-24 | Toyota Motor Corp | Hybrid vehicle |
DE102017100518A1 (en) * | 2016-02-04 | 2017-08-10 | Umicore Ag & Co. Kg | System and process for exhaust gas purification while avoiding nitrous oxide |
CN106609691B (en) * | 2017-02-23 | 2023-03-14 | 河南科技大学 | Pipeline system for SCR (selective catalytic reduction) post-treatment system and SCR post-treatment system |
JP7052785B2 (en) * | 2019-10-09 | 2022-04-12 | トヨタ自動車株式会社 | Hybrid vehicle and its control method |
JP2022094138A (en) * | 2020-12-14 | 2022-06-24 | トヨタ自動車株式会社 | Exhaust emission control device for internal combustion engine |
CN114320547B (en) * | 2021-12-28 | 2023-06-20 | 联合汽车电子有限公司 | Regeneration method, device, equipment, system and storage medium of particle trap |
US11686236B1 (en) * | 2022-02-18 | 2023-06-27 | Saudi Arabian Oil Company | Device for the reduction of ammonia and nitrogen oxides emissions |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09133032A (en) * | 1995-11-10 | 1997-05-20 | Toyota Motor Corp | Exhaust emission control system for internal combustion engine |
JP2000008833A (en) * | 1998-06-22 | 2000-01-11 | Toyota Motor Corp | Exhaust gas purifier of internal combustion engine |
US20010049936A1 (en) * | 1996-04-19 | 2001-12-13 | Kenneth Voss E. | System for reduction of harmful exhaust emissions from diesel engines |
US20020198098A1 (en) * | 2000-04-26 | 2002-12-26 | Shinji Yamamoto | Exhaust gas purifying catalyst and method of producing same |
US20060153761A1 (en) * | 2003-01-02 | 2006-07-13 | Daimlerchrysler Ag | Exhaust gas aftertreatment installation and method |
US20070028601A1 (en) * | 2003-04-05 | 2007-02-08 | Daimlerchrysler Ag | Device and method for exhaust gas aftertreatment |
US20090183495A1 (en) * | 2006-06-12 | 2009-07-23 | Isuzu Motors Limited | Method of Purifying Exhaust Gas and Exhaust Gas Purification System |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3513536B2 (en) * | 1995-01-27 | 2004-03-31 | トヨタ自動車株式会社 | Exhaust gas purification method and exhaust gas purification device |
JP4016420B2 (en) * | 2002-10-08 | 2007-12-05 | 日産自動車株式会社 | Exhaust gas purification catalyst system |
JP4729990B2 (en) * | 2005-06-10 | 2011-07-20 | トヨタ自動車株式会社 | Exhaust gas purification device for internal combustion engine |
JP4463248B2 (en) * | 2006-07-31 | 2010-05-19 | 本田技研工業株式会社 | Control method for NOx reduction system |
DE502007003465D1 (en) * | 2007-02-23 | 2010-05-27 | Umicore Ag & Co Kg | Catalytically activated diesel particulate filter with ammonia barrier effect |
JP4304539B2 (en) * | 2007-05-17 | 2009-07-29 | いすゞ自動車株式会社 | NOx purification system control method and NOx purification system |
JP2009074426A (en) * | 2007-09-20 | 2009-04-09 | Toyota Motor Corp | Controller of internal combustion engine |
JP2010209737A (en) * | 2009-03-09 | 2010-09-24 | Toyota Motor Corp | Exhaust emission control device for internal combustion engine |
-
2011
- 2011-10-13 KR KR1020110104662A patent/KR101317411B1/en active IP Right Grant
-
2012
- 2012-05-15 JP JP2012111395A patent/JP6054057B2/en active Active
- 2012-06-08 CN CN201210243278.2A patent/CN103046985B/en active Active
- 2012-06-21 DE DE102012210547.6A patent/DE102012210547B4/en active Active
- 2012-06-27 US US13/534,823 patent/US20130095002A1/en not_active Abandoned
-
2015
- 2015-10-19 US US14/886,679 patent/US20160040569A1/en not_active Abandoned
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09133032A (en) * | 1995-11-10 | 1997-05-20 | Toyota Motor Corp | Exhaust emission control system for internal combustion engine |
US20010049936A1 (en) * | 1996-04-19 | 2001-12-13 | Kenneth Voss E. | System for reduction of harmful exhaust emissions from diesel engines |
JP2000008833A (en) * | 1998-06-22 | 2000-01-11 | Toyota Motor Corp | Exhaust gas purifier of internal combustion engine |
US20020198098A1 (en) * | 2000-04-26 | 2002-12-26 | Shinji Yamamoto | Exhaust gas purifying catalyst and method of producing same |
US20060153761A1 (en) * | 2003-01-02 | 2006-07-13 | Daimlerchrysler Ag | Exhaust gas aftertreatment installation and method |
US20070028601A1 (en) * | 2003-04-05 | 2007-02-08 | Daimlerchrysler Ag | Device and method for exhaust gas aftertreatment |
US20090183495A1 (en) * | 2006-06-12 | 2009-07-23 | Isuzu Motors Limited | Method of Purifying Exhaust Gas and Exhaust Gas Purification System |
Also Published As
Publication number | Publication date |
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KR20130040269A (en) | 2013-04-24 |
JP2013087769A (en) | 2013-05-13 |
JP6054057B2 (en) | 2016-12-27 |
CN103046985B (en) | 2017-06-13 |
DE102012210547B4 (en) | 2023-09-28 |
CN103046985A (en) | 2013-04-17 |
KR101317411B1 (en) | 2013-10-18 |
US20130095002A1 (en) | 2013-04-18 |
DE102012210547A1 (en) | 2013-04-18 |
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