WO2019185300A1 - Exhaust gas treatment system for vehicle and exhaust gas treatment method - Google Patents

Exhaust gas treatment system for vehicle and exhaust gas treatment method Download PDF

Info

Publication number
WO2019185300A1
WO2019185300A1 PCT/EP2019/055242 EP2019055242W WO2019185300A1 WO 2019185300 A1 WO2019185300 A1 WO 2019185300A1 EP 2019055242 W EP2019055242 W EP 2019055242W WO 2019185300 A1 WO2019185300 A1 WO 2019185300A1
Authority
WO
WIPO (PCT)
Prior art keywords
real
exhaust gas
scr apparatus
scr
time
Prior art date
Application number
PCT/EP2019/055242
Other languages
French (fr)
Inventor
Xiaobin Chen
Liangshan XIANG
Weiqing LIN
Dawei Zhang
Original Assignee
Robert Bosch Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch Gmbh filed Critical Robert Bosch Gmbh
Publication of WO2019185300A1 publication Critical patent/WO2019185300A1/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N11/00—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity
    • F01N11/002—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity the diagnostic devices measuring or estimating temperature or pressure in, or downstream of the exhaust apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • 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
    • F01N3/206—Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents
    • 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]
    • F01N3/208—Control of selective catalytic reduction [SCR], e.g. dosing of reducing agent
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N9/00—Electrical control of exhaust gas treating apparatus
    • 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
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/0047—Controlling exhaust gas recirculation [EGR]
    • F02D41/005—Controlling exhaust gas recirculation [EGR] according to engine operating conditions
    • F02D41/0055—Special engine operating conditions, e.g. for regeneration of exhaust gas treatment apparatus
    • 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
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/0047—Controlling exhaust gas recirculation [EGR]
    • F02D41/0077—Control of the EGR valve or actuator, e.g. duty cycle, closed loop control of position
    • 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
    • F02D41/14—Introducing closed-loop corrections
    • F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
    • F02D41/1444—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases
    • F02D41/146—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an NOx content or concentration
    • F02D41/1461—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an NOx content or concentration of the exhaust gases emitted by the engine
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/14—Introducing closed-loop corrections
    • F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
    • F02D41/1444—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases
    • F02D41/146—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an NOx content or concentration
    • F02D41/1463—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an NOx content or concentration of the exhaust gases downstream of exhaust gas treatment apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2550/00—Monitoring or diagnosing the deterioration of exhaust systems
    • F01N2550/02—Catalytic activity of catalytic converters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/02—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor
    • F01N2560/026—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor for measuring or detecting NOx
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/06—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being a temperature sensor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/14—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics having more than one sensor of one kind
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/02—Adding substances to exhaust gases the substance being ammonia or urea
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D21/00—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas
    • F02D21/06—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air
    • F02D21/08—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air the other gas being the exhaust gas of engine
    • F02D2021/083—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air the other gas being the exhaust gas of engine controlling exhaust gas recirculation electronically
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/40—Engine management systems

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Exhaust-Gas Circulating Devices (AREA)
  • Combined Controls Of Internal Combustion Engines (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)

Abstract

The present application relates to an exhaust gas treatment system for a vehicle, comprising: an EGR apparatus (110), configured to recirculate a portion of exhaust gas in an exhaust pipeline (102) of a vehicle engine to a combustion chamber (100); an SCR apparatus (120), disposed in the exhaust pipeline (102) of the engine and configured to reduce an amount of NOx in exhaust gas in the exhaust pipeline (102) via a catalytic reduction reaction under the action of a catalyst; and a balance control module (130), configured to perform real-time detection of real-time operating parameters of the SCR apparatus (120), obtain a real-time operating state of the SCR apparatus (120) from one or more of the real- time operating parameters, and automatically control the operation of the EGR apparatus (110) when the real-time operating state of the SCR apparatus (120) is unable to reach a predetermined operating state, in order to cause the real-time operating state of the SCR apparatus (120) to reach the predetermined operating state. The present application also provides an exhaust gas treatment method using the abovementioned exhaust gas treatment system.

Description

Description
Exhaust gas treatment system for vehicle and exhaust gas treatment method
Technical field
The present application relates to an exhaust gas treatment system for a vehicle, in particular to an exhaust gas treatment system comprising a selective catalytic reduction (SCR) apparatus and an exhaust gas recirculation (EGR) apparatus. In addition, the present application relates to an exhaust gas treatment method using the exhaust gas treatment system.
Background art
The deployment of an SCR apparatus in a vehicle to reduce the NOx content of exhaust gas discharged from a vehicle engine is well known. The apparatus injects an aqueous urea solution into an engine exhaust pipeline; upon coming into contact with high-temperature exhaust gas, the aqueous urea decomposes to produce ammonia (NH3); as a reducing agent, the ammonia undergoes a reduction reaction in an SCR catalytic converter with NOx in the exhaust gas under the action of an SCR catalyst, thereby producing nitrogen and water, and thereby reducing the NOx content.
The deployment of an EG R apparatus in a vehicle to reduce the amount of NOx produced by the combustion of fuel in an engine combustion chamber is also well known. The apparatus recirculates a portion of exhaust gas in an engine exhaust pipeline back into a gas intake pipeline of the engine, and into the combustion chamber, inhibiting the production of NOx in the combustion chamber, such that the NOx content of exhaust gas discharged from the combustion chamber is reduced. However, in an exhaust gas treatment system in which both an SCR apparatus and an EGR apparatus are deployed, the two apparatuses act simultaneously and influence each other, and it is very difficult for both apparatuses to be in an optimal operating state with maximum efficiency. In particular, an SCR apparatus can only have the predetermined effect within a specific range of intake gas temperatures; when the exhaust gas temperature is too high, e.g. higher than 550°C, the NH3 might be oxidized and not react with NOx; when the exhaust gas temperature is too low, e.g. lower than 200°C, the catalyst activity is reduced, and the reaction slows down. Furthermore, in low- temperature situations, the risk of crystallization of urea will also increase markedly. As a direct result of low SCR apparatus efficiency, the amount of NOx finally discharged into the atmosphere may exceed the regulatory standard.
In addition, if the weighting of the action of the EGR apparatus is too high, an excessive amount of exhaust gas returning to the combustion chamber will significantly reduce the fuel combustion efficiency and economy; if the opposite is true, the inhibition of NOx production will not be significant.
It is hoped that a form of balance control can be provided between an SCR apparatus and an EGR apparatus operating simultaneously.
Content of the invention
An object of the present application is to provide effective balance control of the operation of an SCR apparatus and an EG R apparatus in an exhaust gas treatment system in which both apparatuses are provided, such that the SCR apparatus is kept within the high-efficiency zone of its operation while the EGR apparatus has a suitable operating state.
To this end, the present application provides an exhaust gas treatment system for a vehicle, comprising: an EG R apparatus, configured to recirculate a portion of exhaust gas in an exhaust pipeline of a vehicle engine to a combustion chamber; an SCR apparatus, disposed in the exhaust pipeline of the engine and configured to reduce an amount of NOx in exhaust gas in the exhaust pipeline via a catalytic reduction reaction under the action of a catalyst; and a balance control module, configured to perform real-time detection of real-time operating parameters of the SCR apparatus, obtain a real-time operating state of the SCR apparatus therefrom, and automatically control the operation of the EG R apparatus when the real-time operating state of the SCR apparatus is unable to reach a predetermined operating state, in order to cause the real-time operating state of the SCR apparatus to reach the predetermined operating state.
Specifically, the balance control module comprises a measurement unit performing a measurement function, and a determining/control unit performing a determining/control function, and optionally further comprises a calculation unit performing a calculation operation, and a storage unit. In the present application, the real-time operating state and the predetermined operating state are a real time operating efficiency and a predetermined operating efficiency respectively.
According to the present application, the balance control module is configured to firstly determine by means of the determining/control unit whether a real-time gas intake temperature of the SCR apparatus measured by a temperature sensor is lower than a gas intake temperature lower limit value of the SCR apparatus, and then determine, only when a result is“no”, whether the real-time operating efficiency of the SCR apparatus is lower than the predetermined operating efficiency of the SCR apparatus. The balance control module is configured to control the operation of the EGR apparatus to increase the amount of exhaust gas recirculated into the combustion chamber, when the real-time gas intake temperature of the SCR apparatus is lower than a temperature lower limit value of high-efficiency operation of the SCR apparatus, and when the real-time operating efficiency of the SCR apparatus is lower than the predetermined operating efficiency of the SCR apparatus; this reduces the bare-machine emissions of the engine, and at the same time can increase the exhaust temperature, thereby causing the SCR to operate to the high-efficiency zone again, so that the engine emissions attain the regulatory requirements.
According to another aspect of the present application, a method for using the abovementioned exhaust gas treatment system to treat exhaust gas is provided, the method comprising the use of the balance control module: i) to perform real-time measurement of a real-time operating parameter of the SCR apparatus; ii) to obtain the real-time operating state of the SCR apparatus using the measured real-time operating parameter; and iii) to automatically control the operation of the EG R apparatus when the real-time operating state of the SCR apparatus is unable to reach the predetermined operating state, in order to cause the real-time operating state of the SCR apparatus to reach the predetermined operating state, returning to step i) when the real-time operating state of the SCR apparatus reaches the predetermined operating state. The action of controlling the operation of the EG R apparatus comprises increasing a degree of opening of an EGR valve in the EGR apparatus in order to increase the amount of exhaust gas recirculated into the combustion chamber of the engine.
Due to the provision of the balance control module, the exhaust gas treatment system of the present application can monitor the real-time operating state of the SCR apparatus in real time, and automatically control the operation of the EGR apparatus located upstream thereof by feedback, in response to the real-time operating state of the SCR apparatus being unable to reach the predetermined operating state, in order to achieve the technical objective of keeping the SCR apparatus in an optimal operating state, thereby ensuring that NOx in the exhaust gas is fully removed before discharge into the atmosphere, and bringing the fuel consumption of the vehicle to an optimum level, to comply with the relevant exhaust gas emission regulations, such as EUVI.
Description of the accompanying drawings
Those skilled in the art will gain a full understanding of the abovementioned and other features and advantages of the present application through the particular embodiments described in detail below with reference to the accompanying drawings. In the drawings:
Fig. 1 shows a simplified block diagram of a part of an embodiment of the exhaust gas treatment system according to the present application; and
fig. 2 shows a flow chart of an embodiment of the exhaust gas treatment method according to the present application. Particular embodiments
An exhaust gas treatment system for a vehicle according to the present application is described below with reference to fig. 1. The exhaust gas treatment system shown in this embodiment comprises an exhaust gas recirculation apparatus (referred to as an “EGR apparatus” hereinbelow) 110, a selective catalytic reduction apparatus (referred to as an“SCR apparatus” hereinbelow) 120 disposed downstream of the EG R apparatus 110 in an exhaust gas flow direction in an exhaust pipeline 102 of a vehicle engine, and a balance control module 130 in communicative connection with both.
Specifically, the EGR apparatus 110 is configured to recirculate at least a portion of exhaust gas from the exhaust pipeline 102 of the vehicle engine to a gas intake pipeline 104 of the engine, then supply this portion of exhaust gas into a combustion chamber 100 of the engine, thereby reducing the oxygen content in the combustion chamber 100 and reducing the fuel combustion temperature in the combustion chamber 100, and thereby inhibiting the chemical reaction of nitrogen and oxygen in the combustion chamber 100, and reducing the NOx content of exhaust gas discharged from the combustion chamber 100. The EG R apparatus 110 comprises an EGR valve for controlling the amount of exhaust gas recirculated from the exhaust pipeline 102 of the engine into the gas intake pipeline 104.
The SCR apparatus 120 is disposed on the exhaust pipeline 102, downstream of the EG R apparatus 110, and is configured to supply an aqueous urea solution to the exhaust pipeline 102 of the engine; urea is decomposed under the action of exhaust gas heat to produce ammonia, which undergoes a catalytic reduction reaction as a reducing agent under the action of a catalyst supplied into the exhaust pipeline 102, converting NOx in exhaust gas to nitrogen and water which are harmless to the atmosphere. The SCR apparatus 120 comprises one or more of the following: a urea reservoir for storing urea, a urea delivery device for supplying the aqueous urea solution to the exhaust pipeline 102, an injector for injecting the aqueous urea solution into the exhaust pipeline 102, a metering device for metering the amount of aqueous urea solution supplied into the exhaust pipeline 102, a catalytic converter, a temperature sensor, and sensors of other types, etc.
In this embodiment, the reducing agent is the aqueous urea solution; in other embodiments, other forms of reducing agent may be used, e.g. liquid ammonia, etc.
The balance control module 130 is connected to both the SCR apparatus 120 and the EGR apparatus 110, and is configured to perform real-time detection of real-time operating parameters of the SCR apparatus 120, obtain a real-time operating state of the SCR apparatus 120 from one or more of the real-time operating parameters, and control the operation of the EG R apparatus 110 when the real-time operating state of the SCR apparatus 120 is unable to reach an optimal predetermined operating state, in order to cause the SCR apparatus 120 to reach the predetermined operating state, and finally ensure that the NOx content of vehicle exhaust gas discharged into the atmosphere complies with a specific exhaust standard.
Specifically, in the demonstrative embodiment of fig. 1, the balance control module 130 may comprise a measurement unit 1310 for real-time detection of the operation of the SCR apparatus 120, a storage unit 1320 for storing parameters and/or algorithms associated with the exhaust gas treatment system, a calculation unit 1330 for executing various calculation operations, and a determining/control unit 1340 for performing a determination on the basis of a calculation result of the calculation unit 1330 and correspondingly controlling the operation of the EGR apparatus 110.
According to the present invention, the measurement unit 1310 at least comprises an upstream NOx sensor, located upstream of the SCR apparatus 120 and used to detect an upstream NOx content entering the SCR apparatus 120, a downstream NOx sensor located downstream of the SCR apparatus 120 and used to detect a downstream NOx content of exhaust gas after passing through the SCR apparatus 120, and a temperature sensor located upstream of the SCR apparatus 120 and used to detect a real-time gas intake temperature of the SCR apparatus 120. Of course, in other embodiments, the measurement unit 1310 may further comprise any other parameter detection apparatus, e.g. a sensor for detecting an ammonia content of the SCR apparatus 120. According to the principles of the present application, each sensor or electronic device in the measurement unit 1310 may be of any suitable type known to those skilled in the art, may be a corresponding sensor or electronic device already disposed in the vehicle for the purpose of realizing another function, and may be provided separately for the balance control module 130.
In the present application, the real-time operating state of the SCR apparatus 120 may be a real-time operating efficiency, and correspondingly, the predetermined operating state may be a predetermined operating efficiency. The real-time operating efficiency may be obtained by calculation from the upstream NOx content and the downstream NOx content measured by the measurement unit 1310.
A series of parameter values and algorithms which might be used by the exhaust gas treatment system of the present application are pre-stored in the storage unit 1320; these parameter values and algorithms include but are not limited to the predetermined operating efficiency of the SCR apparatus 120; an efficiency calculation algorithm of the SCR apparatus 120; and a gas intake temperature range or upper limit value and lower limit value of the SCR apparatus 120. In an embodiment of the present application, the storage unit 1320 may be a memory of any type known to those skilled in the art, may use a memory already disposed in the vehicle for the purpose of realizing another function, and may be a memory provided separately for the balance control module 130.
The calculation unit 1330 is in communicative connection with the measurement unit 1310 and the storage unit 1320, and is configured to acquire from the measurement unit 1310 the upstream NOx content of the SCR apparatus 120 detected by the upstream NOx sensor and the downstream NOx content of the SCR apparatus 120 detected by the downstream NOx sensor, to acquire from the storage unit 1320 the efficiency calculation algorithm of the SCR apparatus 120, and to calculate the real-time operating efficiency of the SCR apparatus 120. In an embodiment of the present application, the calculation unit 1330 may be a calculation apparatus of any type known to those skilled in the art, may be an existing calculator already disposed in the vehicle for the purpose of realizing another calculation function, and may be a calculator or processor provided separately for the balance control module 130.
The determining/control unit 1340 is in communicative connection with the storage unit 1320 and with both the calculation unit 1330 and the EG R apparatus 110. The determining/control unit 1340 is configured to:
firstly, execute a determining operation a): determining whether the real-time gas intake temperature of the SCR apparatus 120 is lower than the gas intake temperature lower limit value of the SCR apparatus 120;
then execute a determining operation b) in the case where a result of the determining operation a) is “no”: determining whether the real-time operating efficiency of the SCR apparatus 120 is lower than the pre-determined operating efficiency of the SCR apparatus 120; and not execute the determining operation b) in the case where the result of the determining operation a) is“yes”, but instead execute an operation c): controlling the EG R apparatus 110 to increase a degree of opening of the EG R valve;
finally, execute the determining operation c) in the case where a result of the determining operation b) is“yes”: controlling the EG R apparatus 110 to increase the degree of opening of the EG R valve.
In the determining operation a), the action of determining whether the real time gas intake temperature of the SCR apparatus 120 is lower than the gas intake temperature lower limit value of the SCR apparatus 120, comprises acquiring from the measurement unit 1310 the real-time gas intake temperature of the SCR apparatus 120 detected by the temperature sensor, acquiring from the storage unit 1320 the gas intake temperature lower limit value of the SCR apparatus 120, and comparing the two.
In the determining operation b), the action of determining whether the real time operating efficiency of the SCR apparatus 120 is lower than the pre determined operating efficiency of the SCR apparatus 120, comprises acquiring from the calculation unit 1330 the real-time operating efficiency of the SCR apparatus 120, acquiring from the storage unit 1320 the predetermined operating efficiency of the SCR apparatus 120, and comparing the two.
In the operation c), the action of controlling the operation of the EGR apparatus 110, such that the degree of opening of the EG R valve increases, improves the operating efficiency of the EGR apparatus 110, thereby increasing the amount of exhaust gas recirculated from the engine exhaust pipeline 102 into the gas intake pipeline 104 of the combustion chamber 100. In this way, the content of oxygen in the combustion chamber 100 is reduced, hence the generation of NOx as described above is inhibited, and at the same time, the combustion temperature of fuel in the combustion chamber 100 is reduced, but the temperature of exhaust gas discharged from the combustion chamber 100, i.e. the gas intake temperature of the SCR apparatus 120, rises.
According to the present application, with regard to the SCR apparatus 120, using the balance control module 130 of the exhaust gas treatment system, by i) detecting in real time the real-time operating parameters of the SCR apparatus 120, and then obtaining the real-time operating state thereof; ii) comparing the real-time operating state with the predetermined operating state; and iii) controlling the operation of the EG R apparatus 110 upstream of the SCR apparatus 120 to change the upstream NOx content and gas intake temperature of the SCR apparatus 120 when the real-time operating state is not good or lower than or unable to reach the predetermined operating state, the objective of optimizing the operation of the SCR apparatus 120 such that the efficiency thereof reaches the predetermined operating efficiency is achieved, in order to ensure that the NOx content of exhaust gas discharged from the SCR apparatus 120 is able to comply with a specific emission standard, e.g. EUVI.
Advantageously, the exhaust gas treatment system according to the present application can keep the operation of the EG R apparatus 110 at a preset operating level. Specifically, due the provision of the balance control module 130, the operation of the EGR apparatus 110 is changed only when the real-time gas intake temperature of the SCR apparatus 120 is lower than the gas intake temperature lower limit value of the SCR apparatus 120, and when the real-time operating efficiency of the SCR apparatus 120 is lower than the predetermined operating efficiency thereof, to increase the amount of exhaust gas recirculated into the combustion chamber 100. This avoids a situation where too little exhaust gas is recirculated into the combustion chamber via the EG R apparatus 110, the content of NOx in the exhaust gas discharged from the combustion chamber 100 is still too high, and the SCR apparatus 120 is unable to achieve full reduction, with the result that NOx in exhaust gas discharged into the atmosphere exceeds the regulatory standard. In addition, no change is made to the operation of the EG R apparatus 110 when the real-time operating efficiency of the SCR apparatus 120 is not lower than the predetermined operating efficiency thereof; this can avoid a situation where too much exhaust gas is recirculated into the combustion chamber by the EGR apparatus 110, adversely affecting engine performance, e.g. motive power.
Optionally, the exhaust gas treatment system of the present application may as required further comprise one or both of a particulate trap (DPF) and a particulate oxidizer (POC).
Fig. 2 shows schematically a flow chart of a method for using the abovementioned exhaust gas treatment system to treat exhaust gas.
Firstly, in step 210, the upstream and downstream NOx sensors of the measurement unit 1310 are used to measure the upstream NOx content and the downstream NOx content of the SCR apparatus of the vehicle in the course of travel, and the temperature sensor of the measurement unit 1310 is used to measure the real-time gas intake temperature of the SCR apparatus 120.
Next, in step 220, the calculation unit 1330 receives the upstream NOx content and downstream NOx content from the measurement unit 1310, acquires the efficiency calculation algorithm of the SCR apparatus 120 from the storage unit 1320, and calculates the real-time operating efficiency of the SCR apparatus 120. For example, the SCR operating efficiency may be represented by the NOx conversion rate.
Then in step 230, the determining/control unit 1340 obtains the real-time gas intake temperature of the SCR apparatus 120 from the measurement unit 1310, obtains the gas intake temperature lower limit value of the SCR apparatus 120 from the storage unit 1320, and determines whether the real-time gas intake temperature of the SCR apparatus 120 is lower than the gas intake temperature lower limit value of the SCR apparatus 120. If the result is“no” then step 240 is performed, otherwise step 250 is performed.
In step 240, the determining/control unit 1340 obtains the real-time operating efficiency of the SCR apparatus 120 from the calculation unit 1330, extracts the predetermined operating efficiency from the storage unit 1320, and determines whether the real-time operating efficiency is lower than the predetermined operating efficiency. When the real-time operating efficiency is lower than the predetermined operating efficiency, the method continues with step 250; otherwise the method returns to step 210, i.e. measuring the next set of real-time data, then repeating the abovementioned steps.
In step 250, the method enters an engine control mode. In this step, in response to the real-time gas intake temperature of the SCR apparatus 120 being lower than the gas intake temperature lower limit value of the SCR apparatus 120, or in response to the real-time operating efficiency of the SCR apparatus 120 being lower than the predetermined operating efficiency, the determining/control unit 1340 automatically controls the EGR apparatus by feedback, increasing the degree of opening of the EG R valve in the EG R apparatus. In this way, a greater amount of exhaust gas from the exhaust pipeline is recirculated into the combustion chamber 100 of the engine, reducing the reaction rate of the combustion process in the engine combustion chamber 100, extending the ignition delay, inhibiting the chemical combination of nitrogen and oxygen and hence slowing down the generation of NOx. At the same time, the exhaust gas temperature is increased, so the gas intake temperature of the SCR apparatus 120 rises, and the NOx content of the exhaust gas entering the SCR apparatus 120 falls. When step 250 has been completed, the method returns to step 210, i.e. performing the next set of measurements and repeating the abovementioned steps. Optionally, the method further comprises performing step 260, i.e. monitoring real-time emissions of the vehicle, when it is determined in step 240 that the real time operating efficiency of the SCR apparatus 120 has reached the predetermined operating efficiency.
By balancing operation between the EG R apparatus and the SCR apparatus, the exhaust gas treatment system comprising the balance control module 130 according to the present invention optimizes the fuel consumption of the vehicle in different environmental conditions while meeting specific emission requirements.
The exhaust gas treatment system according to the present application may be applied to diesel engines, petrol engines and gas fuel engines, as well as other engines known in the art.
A detailed explanation has been given above on the basis of the embodiments shown in the figures, but the present application is not limited to the details described above and shown in the figures. On the contrary, various amendments, changes or equivalent substitutions may be made to the details of the present application without departing from the substance and scope defined by the attached claims.

Claims

Claims
1. Exhaust gas treatment system for a vehicle, comprising:
an EG R apparatus (110), configured to recirculate a portion of exhaust gas in an exhaust pipeline (102) of an engine of the vehicle to a combustion chamber (100) of the vehicle;
an SCR apparatus (120), disposed in the exhaust pipeline (102) of the vehicle engine and configured to reduce an amount of NOx in exhaust gas in the exhaust pipeline (102) via a reduction reaction; and
a balance control module (130), configured to perform real-time detection of real-time operating parameters of the SCR apparatus (120), obtain a real-time operating state of the SCR apparatus (120) from one or more of the real-time operating parameters, and automatically control the operation of the EGR apparatus (110) when the real-time operating state of the SCR apparatus (120) is unable to reach a predetermined operating state, in order to cause the real-time operating state of the SCR apparatus (120) to reach the predetermined operating state.
2. Exhaust gas treatment system according to Claim 1, wherein the real-time operating state and the predetermined operating state are a real-time operating efficiency and a predetermined operating efficiency respectively.
3. Exhaust gas treatment system according to Claim 1 or 2, wherein the balance control module (130) comprises a measurement unit (1310) for performing real-time detection of real-time operating parameters of the SCR apparatus (120), and a determining/control unit (1340) configured to control the operation of the EGR apparatus (110) when the real-time operating state of the SCR apparatus (120) is unable to reach the predetermined operating state, wherein the measurement unit (1310) is in communicative connection with the SCR apparatus (120), and the determining/control unit (1340) is in communicative connection with the EGR apparatus (110).
4. Exhaust gas treatment system according to Claim 3, wherein the balance control module (130) further comprises a calculation unit (1330) for calculating the real-time operating state from one or more of the real-time operating parameters, and a storage unit (1320) for storing an algorithm and a parameter associated with the exhaust gas treatment system, wherein the measurement unit (1310) is also in communication connection with the calculation unit (1330), and the determining/control unit (1340) is also in communicative connection with the calculation unit (1330) and the storage unit (1320).
5. Exhaust gas treatment system according to Claim 4, wherein the determining/control unit (1340), the calculation unit (1330) and the storage unit (1320) are provided separately, or are configured as a single unit capable of performing the abovementioned calculation, storage and comparison functions.
6. Exhaust gas treatment system according to Claim 5, wherein the measurement unit (1310) comprises: an upstream NOx sensor for detecting an upstream NOx content entering the SCR apparatus (120), a downstream NOx sensor for detecting a downstream NOx content discharged from the SCR apparatus (120), and a temperature sensor for detecting a real-time gas intake temperature of the SCR apparatus (120), wherein the real-time operating efficiency is expressed as an NOx conversion rate calculated from the upstream NOx content and the downstream NOx content.
7. Exhaust gas treatment system according to Claim 6, wherein the algorithm and the parameter associated with the exhaust gas treatment system at least comprise a predetermined operating efficiency of the SCR apparatus (120), an operating efficiency algorithm of the SCR apparatus (120), and a gas intake temperature range or upper limit value and lower limit value of the SCR apparatus (120) .
8. Exhaust gas treatment system according to Claim 7, wherein the balance control module (130) is configured to firstly determine by means of the determining/control unit (1340) whether the real-time gas intake temperature of the SCR apparatus (120) measured by the temperature sensor is lower than the gas intake temperature lower limit value of the SCR apparatus (120), and then determine, only when a result is“no”, whether the real-time operating efficiency of the SCR apparatus (120) is lower than the predetermined operating efficiency of the SCR apparatus (120).
9. Exhaust gas treatment system according to Claim 8, wherein the balance control module (130) is configured to control the EGR apparatus (110) to increase the amount of exhaust gas recirculated into the combustion chamber, when the real-time gas intake temperature of the SCR apparatus (120) is lower than the gas intake temperature lower limit value of the SCR apparatus (120), and when the real-time operating efficiency of the SCR apparatus (120) is lower than the predetermined operating efficiency of the SCR apparatus (120).
10. Exhaust gas treatment system according to Claim 3, wherein the measurement unit (1310) further comprises a sensor for performing real-time detection of one or more of the following parameters: a degree of ageing of an element in the SCR apparatus (120); and an ammonia content in the SCR apparatus (120).
11. Method for using the exhaust gas treatment system according to any one of Claims 1 - 10 to treat exhaust gas, the method comprising the use of the balance control module (130):
i) to perform real-time measurement of a real-time operating parameter of the SCR apparatus (120);
ii) to obtain the real-time operating state of the SCR apparatus (120) using the measured real-time operating parameter; and iii) to automatically control the operation of the EGR apparatus (110) when the real-time operating state of the SCR apparatus (120) is unable to reach the predetermined operating state, in order to cause the real-time operating state of the SCR apparatus (120) to reach the predetermined operating state, returning to step i) when the real-time operating state of the SCR apparatus (120) reaches the predetermined operating state.
12. Method according to Claim 11, wherein the action of controlling the operation of the EG R apparatus (110) comprises increasing a degree of opening of an EGR valve in the EGR apparatus (110) in order to increase the amount of exhaust gas recirculated into the combustion chamber of the engine.
13. Method according to Claim 12, wherein step i) comprises detecting an upstream NOx content of the SCR apparatus (120), detecting a downstream NOx content of the SCR apparatus (120), and detecting a real-time gas intake temperature of the SCR apparatus (120).
14. Method according to Claim 13, wherein step iii) comprises: firstly determining whether the real-time gas intake temperature of the SCR apparatus (120) is lower than a gas intake temperature lower limit value of the SCR apparatus (120), and then determining, only when a result is“no”, whether a real time operating efficiency of the SCR apparatus (120) is lower than a predetermined operating efficiency thereof.
15. Method according to Claim 14, wherein a step of controlling the operation of the EG R apparatus (110) is performed when the real-time gas intake temperature of the SCR apparatus (120) is lower than the gas intake temperature lower limit value of the SCR apparatus (120), and when the real-time operating efficiency of the SCR apparatus (120) is lower than the predetermined operating efficiency of the SCR apparatus (120), to increase the amount of exhaust gas recirculated into the combustion chamber.
PCT/EP2019/055242 2018-03-29 2019-03-04 Exhaust gas treatment system for vehicle and exhaust gas treatment method WO2019185300A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201810268847.6 2018-03-29
CN201810268847.6A CN110318893A (en) 2018-03-29 2018-03-29 Exhaust treatment system and waste gas processing method for vehicle

Publications (1)

Publication Number Publication Date
WO2019185300A1 true WO2019185300A1 (en) 2019-10-03

Family

ID=65686845

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2019/055242 WO2019185300A1 (en) 2018-03-29 2019-03-04 Exhaust gas treatment system for vehicle and exhaust gas treatment method

Country Status (2)

Country Link
CN (1) CN110318893A (en)
WO (1) WO2019185300A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110162350A1 (en) * 2010-01-01 2011-07-07 Cummins Intellectual Properties, Inc. Engine and exhaust aftertreatment control
US20140360163A1 (en) * 2013-06-05 2014-12-11 Ford Global Technologies, Llc System and method for controlling an engine that includes low pressure egr
DE102014018037A1 (en) * 2014-12-05 2015-06-25 Daimler Ag A method of determining a NOx reduction performance of a NOx reduction catalyst device disposed in an exhaust passage of an automotive internal combustion engine

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110162350A1 (en) * 2010-01-01 2011-07-07 Cummins Intellectual Properties, Inc. Engine and exhaust aftertreatment control
US20140360163A1 (en) * 2013-06-05 2014-12-11 Ford Global Technologies, Llc System and method for controlling an engine that includes low pressure egr
DE102014018037A1 (en) * 2014-12-05 2015-06-25 Daimler Ag A method of determining a NOx reduction performance of a NOx reduction catalyst device disposed in an exhaust passage of an automotive internal combustion engine

Also Published As

Publication number Publication date
CN110318893A (en) 2019-10-11

Similar Documents

Publication Publication Date Title
CN109944666B (en) Model-based SCR system reducing agent supply amount self-adaptive correction method
US10001042B2 (en) Systems, methods, and apparatus for reductant dosing in an SCR aftertreatment system
US8474248B2 (en) Model based method for selective catalyst reducer urea dosing strategy
US8726641B2 (en) Method for controlling injection of diesel exhaust fluid into an exhaust pipe of an internal combustion engine
CN110645076B (en) NH based on model3Leak diagnosis method
US10100695B2 (en) Exhaust fluid dosing control system and method
US20130263575A1 (en) System and method for controlling an exhaust system having a selective catalyst reduction component
US20090199541A1 (en) Method for operating an internal combustion engine and device for carrying out the method
US20150308321A1 (en) Exhaust emission prediction system and method
WO2019019046A1 (en) Injection amount control method and device for scr urea injection system in engine
KR102315788B1 (en) Systems and methods for controlling aftertreatment systems
US20150059317A1 (en) System and method for enhancing the performance of a selective catalytic reduction device
US20200049048A1 (en) Method of monitoring an scr catalytic converter
EP2940280B1 (en) Fuel-cetane-number estimation method and apparatus
AU2016201027B2 (en) Systems and methods for determining the quantity of a combustion product in a vehicle exhaust
CN109882270B (en) Internal combustion engine nitrogen oxide emission closed-loop control system for in-cylinder ionic current and urea injection
JP2013545918A (en) A method for detecting urea deposits in an exhaust line of a vehicle such as an automobile, a method for desorbing urea deposits, and a vehicle such as an automobile adapted to such a method
US10851725B2 (en) Fuel content detection based on a measurement from a sensor and a model estimation of the measurement
US10145284B2 (en) Exhaust after-treatment system including sliding mode ammonia controller
CN109681298B (en) Control system for urea injection self-adaptive correction based on NOx sensor
CA3125388A1 (en) Ammonia storage capacity of scr catalyst unit
CN110857650B (en) Semi-empirical engine exhaust smoke model
US9228467B2 (en) Urea injection controller for a motorized system
WO2019185300A1 (en) Exhaust gas treatment system for vehicle and exhaust gas treatment method
US10443465B2 (en) Engine exhaust system and control system for an engine exhaust system

Legal Events

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

Ref document number: 19709428

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19709428

Country of ref document: EP

Kind code of ref document: A1