CN102441327B - Operating methods for selective catalytic reduction of NOx - Google Patents

Operating methods for selective catalytic reduction of NOx Download PDF

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Publication number
CN102441327B
CN102441327B CN201110296626.8A CN201110296626A CN102441327B CN 102441327 B CN102441327 B CN 102441327B CN 201110296626 A CN201110296626 A CN 201110296626A CN 102441327 B CN102441327 B CN 102441327B
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China
Prior art keywords
agent material
flow
air
catalyst
gas
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CN201110296626.8A
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Chinese (zh)
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CN102441327A (en
Inventor
T.M.斯隆
K.L.佩里
D.L.希尔登
N.D.布林克曼
J.H.李
M.B.维奥拉
S.J.施米格
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GM Global Technology Operations LLC
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GM Global Technology Operations LLC
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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
    • F01N9/00—Electrical control of exhaust gas treating 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
    • F01N3/2066—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
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/03—Adding substances to exhaust gases the substance being hydrocarbons, e.g. engine fuel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/06—Adding substances to exhaust gases the substance being in the gaseous form
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2900/00—Details of electrical control or of the monitoring of the exhaust gas treating apparatus
    • F01N2900/06—Parameters used for exhaust control or diagnosing
    • F01N2900/18—Parameters used for exhaust control or diagnosing said parameters being related to the system for adding a substance into the exhaust
    • 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

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

Abstract

Where oxygenated hydrocarbons, such as ethanol, may be considered for use as a reductant to be added to diesel or gasoline engine exhaust for promoting the catalyzed reduction of NOx to N2, there is a need to continually adjust the amount of the reductant to be added as engine and catalyst operating conditions change. It is found that useful methods, to be practiced using a suitably programmed on-vehicle computer, can be based on a correlation for ethanol, or other specific reductant, with continually measured values of catalyst temperature, the oxygen and NOx contents of the exhaust, and the volumetric flow rate of the exhaust over a reduction catalyst, such as silver supported on alumina, selected for reduction of NOx to nitrogen. Effective amounts of the reductant for substantial reduction of NOx may be reliably determined using at least such parameters.

Description

Operational approach for the SCR of nitrogen oxides
Technical field
The present invention relates to being derived from Diesel engine or the nitrogen oxidation discharged in air-flow of other lean-combustion engine for management (most of be no and no to thing2, it is generically and collectively referred to as nox) SCR method.More particularly it relates to control will Suitable oxidizing hydrocarbons-such as ethanol be added to preparation discharge gas in method so that when flow of exhaust move thus with The no in air-flow will be discharged when base metal, selective reduction catalyst contactxReduced.
Background technology
Diesel engine, some gasoline engines and many HC fuel power-equipments are higher than stoichiometric In the case of air-fuel mass ratio, operating is to obtain improved fuel economy.However, this lean-combustion engine and its He produces oxygen, water and the nitrogen oxides (no with of a relatively high content by power sourcex) hot driving gas.Diesel engine is come Say, from preheating electromotor discharge air-flow temperature generally in the range of about 200 DEG C to 400 DEG C, this temperature depends on Current radio in the fuel consumption (load) of electromotor.Discharge representative, the exemplary composition of gas, by volume about For oxygen 10%, carbon dioxide 6%, carbon monoxide (co) 0.1%, hydro carbons (hc) 180ppm, nox235ppm, remainder is substantially Nitrogen and water.Discharge gas often containing some very little rich carbon granules.And for the situation that HC fuel contains sulfur, Discharge gas from Combustion Source is also possible to containing sulfur dioxide.Expect to process this composition discharging gas so that denitrogenate, two Any substance being discharged into air outside carbonoxide and water.
noxGas generally includes with a small amount of nitrous oxide (n2O) nitrogen oxide (no) and nitrogen dioxide (no2) no Same mixture, this noxGas is difficult to be reduced to nitrogen (n2), this is because heat discharges air-flow relatively high oxygen (o2) content (and Water content).TWC Three Way Catalyst System is used successfully to the electromotor of about stoichiometric air-fuel ratio operating, but ineffective Ground is in this oxygen-enriched discharge gas by noxIt is reduced to acceptable level.
Thin noxCatcher can remove no effectively from discharge air-flowx, but described catcher needs your expensive gold Belong to and their long-term durability does not know.People have been contemplated that selective catalytic reduction method, and wherein lean-burn has discharged gas Through oxidized thus complete unburned hydro carbons to the oxidation of carbon dioxide and water, oxidation from carbon monoxide to carbon dioxide and Some nitrogen oxides (no) are to nitrogen dioxide (no2) oxidation.Agent material-such as nh will be reduced3Or nh3Precursor (carbamide water-soluble Liquid) it is ejected into the discharge air-flow of oxidation, and described air-flow of discharging passes through suitable catalyst with by substantial amounts of noxIt is reduced to nitrogen And water.This practice is referred to as nox" SCR " (scr) because do not affecting discharge air-flow in other oxygen This step is achieved in the case of compound.But carbamide scr and ammonia scr must be the additional reduction agent material of storage on car, and And it is necessary to freeze when avoiding the aqueous solution of carbamide in arctic weather when using carbamide as reducing agent.
Using the no there is more inexpensive, more convenient method realizing the discharge air-flow from lean-combustion enginexReduction To be useful.
Content of the invention
The invention provides a kind of for manage ethanol or other suitable low-molecular-weight oxidizing hydrocarbons (ohc)-such as this The method using and adding of the methanol in class alcohol, propanol, butanol or aldehyde, ethanol or other suitable low-molecular-weight oxidations described Hydro carbons (ohc) as the oxidizing hydrocarbons reducing agent during ohc-scr and be used as oxygen-containing and aqueous lean-burn and discharge gas In noxCatalytic reduction reactor.According to some conditions with discharge the characteristic of air-flow and identify in this manual below Reducing catalyst characteristic, continue to monitor and adjust be added to discharge air-flow oxidizing hydrocarbons amount.Persistently management ohc adds A target be avoid to the ammonia for ohc-scr reactor downstream discharge gas the demand with post processing.Make in a large number It is so that vehicle motor and its total fuel consumption of gas extraction system is minimized with the further object of oxidizing hydrocarbons.
Most of existing vehicle motors are used the burning of HC fuel and air as their power source.Described start Machine includes multiple cylinders, and each cylinder has the powertrain system of propulsion and the reciprocating work of bent axle connecting extremely for vehicle Plug.The present invention is provided in order to by air and fuel computer controls ground, the method that sequentially, is periodically placed to each cylinder. Move back and forth in their corresponding cylinders with piston, controlled air-and-fuel mixture sequentially enters corresponding gas Cylinder, wherein combustible mixture is compressed and is lighted.Burning in each cylinder in power stroke drives piston, is followed by Exhaust stroke-in this exhaust stroke, combustion by-products are drained into exhaust manifold from cylinder, then drain into the discharge of vehicle In gas conduit.Composition in the continuous running of this lean-combustion engine background section of this specification indicated above With produce stable discharge air-flow in temperature range.For example, described fuel can be diesel oil, gasoline, natural gas, liquefied petroleum gas (major part is propane), dimethyl ether, ethanol, ethanol and the mixture of gasoline or similar fuel.Hydrogen can also be used as fuel.
Oxygen-containing and aqueous gas of discharging can be directed to air-flow the passes through, oxidation refonner containing catalyst first, with Oxidation in carbon monoxide and imperfect combustion HC fuel component.Described oxidation refonner may additionally facilitate some nitrogen oxides extremely The oxidation of nitrogen dioxide, to prepare to discharge air-flow, makes this discharge air-flow carry out at downstream in scr reactor Reason, this scr reactor was used for no before discharge air-flow leaves the gas extraction system of vehicle2With other noxGroup Divide and be reduced to nitrogen.According to the present invention, scr reactor upstream appropriate location by oxidizing hydrocarbons add to Discharge air-flow.Example for suitable oxidizing hydrocarbons SCR (ohc-scr) catalyst of the practice of the present invention It is the granular materialss of the silver (or silver oxide) including nano-scale, this material is deposited and is supported on the aluminium oxide granule of micron-scale On grain.For example, the silver catalyst granule being supported can be suitably deposited as multiple gas that be extruded into, ceramic honeycomb material all in one piece Stream through passage aisle wall on shallow layer.
According to the embodiment of the present invention, ethanol (or other suitable oxidizing hydrocarbons) is sprayed into (or otherwise put Enter) the discharge gas of ohc-scr catalyst upstream.In order to the close contact discharging air-flow and ohc-scr catalyst more Effectively affect noxThe reduction of component, as the present inventor's here determines, continues to monitor ohc-scr catalyst and discharges gas Some parameters persistently changing of body, and based on a determination that parameter value persistently adjust and be added to the oxidizing hydrocarbons discharging air-flow Amount is to be allowed to consistent with predetermined policy.
The further diagram of the example of the method according to the invention, below every kind of measured value in four kinds of (at least) parameters Or determination value is persistently obtained and is used for managing the interpolation of oxidizing hydrocarbons: () ohc-scr catalysis with good time time interval The temperature of agent, just no in the discharge gas of ohc-scr catalyst upstreamxThe representative value () of amount and oxygen amount representative It is worth (), and () passes across or through the measured value of the flow rate of discharge gas of catalyst.Speed is moved with regard to flow of exhaust For rate, can measure or determine measured value-such as gas hourly space velocity (sv, h-1) or equivalence value.For example, in the sky determining particular moment Between speed when, using current under the standard conditions of temperature and pressure discharge per hour the unit volume of gas with predetermined The ratio of the fixed volume of ohc-scr catalyst.In the practice of the invention, obtain the discharge gas of ohc-scr catalyst upstream The representative value of the oxygen content accurately and securely in body is important for each determination added to the ohc discharging gas.
For measuring the Current Temperatures of selective reduction catalyst and being used for determining having of the flow rate discharging gas It is available with the proper sensors of value.Similarly, for constantly providing or determining oxygen (for example, with total discharge gas Percentage ratio) and noxThe sensor of the useful instantaneous concentration of (for example, to discharge a few millionths of gas componant) is also to obtain Arrive.By suitably pre-programmed, computer based control system can be used for from corresponding sensor receive such data, and And may be used in such data available to continue and rapidly to analyze these parameters, these parameters are used for determining to be sent out in vehicle It is added to the amount discharging the oxidizing hydrocarbons reducing agent in air-flow in each operating of motivation.This based on sensor and computer System can cooperate as the part work of engine control system or with described engine control system, and described electromotor controls Interpolation and the operating of other electromotors that system be used for-for example measures, determines and controls to the air of electromotor and fuel.
According to the preferred embodiment of the present invention, and by illustrative example, suitable interpolation ohc-scr reducing agent Control system be contemplated that the currency of discharge gas/ohc-scr parameter defined above, and determine and be added to discharge air-flow Reducing agent amount (quality or volume).For example, described control system can be programmed to every mole of noxComponent adds 1 molal quantity The reducing agent (as ethanol) of value, the combination being then based on the currency of described four parameters determines or estimates every in discharge gas Mole noxComponent.Will be described in more detail in book as described below, for any (or each) it is contemplated that being used for specific engines Reducing agent used in concrete ohc-scr system with vehicle, can combine the table with corresponding reducing agent add value by predefined parameter Lattice.Described form can be stored in and control for managing the ongoing vehicle computer added to the reducing agent discharging air-flow In the memorizer of system.It should be appreciated that the same engine in different vehicle can be using different reducing agents, different mechanisms Or device is in order to add reducing agent to the different forms discharging air-flow and parameter combination and corresponding reducing agent add value.Management The main target that ohc adds is to realize noxTo the efficient reduction of nitrogen, make the formation of ammonia in reduction reactor the most simultaneously Littleization, and so that the impact that reducing agent adds the total fuel economy to engine vehicle system is minimized.
In the other embodiment of the present invention, the currency of four parameters can be used in vehicle computer system so that base In the data of storage or calculation procedure using calculating current reduction dosage.
Oxidizing hydrocarbons reduction agent material will be carried in the suitable bin on vehicle, and by suitable conduit quilt Conveying is to be added to electromotor or to discharge air-flow.Preferably, reduction agent material is ethanol, and, ethanol is it is of course possible to be car Fuel or fuel element.For example, when fuel is ethanol and the mixture of diesel fuel or the mixture-example of ethanol and gasoline As oxidizing hydrocarbons/hydrocarbon mixture can be used as additional ohc-scr reduction additive.
By referring to of the detailed description of the specific embodiment of the practice to the present invention, other objects and advantages will become Clear, the practice of the present invention will provide (as nonrestrictive explanation) below in this manual.
Brief description
Fig. 1 be from Diesel engine (or other lean-combustion engines or power-equipment) exhaust manifold pass through discharge gas The schematic diagram of the flowing of discharge air-flow of conduit system, described discharge gas conduit system includes oxidation catalysiss reactor and ohc- Scr catalytic reactor.The explanation of sensing station and reducing agent point of addition is also shown in this figure.
Fig. 2 is the schematic diagram of ohc-scr reactor.In this embodiment, the granule of silver-aluminium oxide catalyst is as painting Layer material is applied to the circulation passage of the honeycomb body of cordierite monolith.Material all in one piece containing this silver-aluminium oxide catalyst is had There is the suitable metal shell closing of the entrance and exit discharging air-flow.
Embodiment
Present invention offer is a kind of, and ethanol and other suitable oxidizing hydrocarbons are used as in the discharge gas of lean-combustion engine The operation strategy of ohc-scr reducing agent.In the case of using silver-aluminium oxide catalyst, ethanol is to noxFor be suitable and excellent The reducing agent of choosing, produces the no of 70%-99% in the range of wider diesel oil and petrol engine operating conditionxTransformation efficiency.Oxygen Change hydro carbons and noxPlacing reaction formation nitrogen, carbon dioxide and water at catalyst with oxygen.By this noxSuitable with reducing agent The material that most of environment being therefore converted into release discharge gas is allowed.
More specifically, in heavily loaded federal test program (heavy-duty federal test procedure Schedule) achieve 81% average no in stepxTransformation efficiency, described heavy duty federal test program sprays into discharge in ethanol Run on 6.6 liters of Diesel engines in the case of air-flow.Ethanol is a kind of particularly efficient ohc-scr reducing agent it is allowed to nox The catalytic temperature of reduction can as little as 250 DEG C.The partial oxidation products of ethanol-such as acetaldehyde, and other alcohol are also equal Efficient ohc-scr reducing agent.By the combination of experiment and mathematical modeling, develop operation strategy during electromotor operating It is used ethanol efficiently to remove no as ohc-scr reducing agent from discharge gasx.Only need to the reduction disclosed in this specification The operation strategy that agent is added slightly changes other oxidizing hydrocarbons (or the mixing of oxidizing hydrocarbons and hydro carbons it is adaptable to ohc-scr Thing) can be used as.
The practice of method controlling reducing agent interpolation is to Diesel engine (or other lean-combustion engines) and its discharge The operating of gas system can be better understood after illustrating, and described discharge gas system is included in discharging gas path For noxThe reactor containing catalyst of the reduction of component.
Fig. 1 is the no for discharging gasxExemplary diesel engine and discharge gas system that the ohc-scr of content is processed The schematic functional block diagram of system.
Referring now to Fig. 1, in figure shows that exemplary engine discharges the schematic functional block diagram of gas system 10.For example, send out Motivation 12 can be gasolene type internal combustion engine, diesel-type explosive motor, hybrid power engine and/or other appropriate types Electromotor.Electromotor 12 produces moment of torsion by the cylinder 14 combusting air/fuel mixture in electromotor 12.Electromotor 12 may include any an appropriate number of cylinder-such as cylinder 14.For example, electromotor 12 may include 2,3,4,5,6,8,10 or 12 Cylinder.
By inlet manifold 13, air is sucked each cylinder 14 of electromotor 12 by order.By electronic throttle controller (etc) 13'''The air throttle 13 activating〃Control the air flow of each cylinder 14 entering electromotor 12.Air with from one Or the fuel of multiple fuel injector 15 mixes to form the mixture of air and fuel, Diesel engine and other lean-burns are sent out For motivation, this mixture has the significantly air-fuel mass ratio higher than the stoichiometric proportion of fuel, this sky of diesel fuel and gasoline Combustion mass ratio is about 14.7.Air/fuel mixture in each cylinder 14 by sequential ignition and burns to produce moment of torsion Thus advancing vehicle.And the burning of air/fuel mixture produces and discharges gas, described discharge gas enters from each cylinder 14 In exhaust manifold 17.Discharge air-flow to flow out from exhaust manifold 17 during electromotor operating as persistently flowing, and flow into discharge Gas system 16.
Discharge gas system 16 to include processing catalyst, sensor, computer control module etc., described part cooperates Discharge nitrogen oxides (no in gas to reducex) amount.Discharge gas system 16 and generally include oxidation catalyst 20, reducing agent material Material ejector 22 and ohc-scr catalyst 24.Described ohc-scr catalyst 24 is generally carried in ohc-scr reaction vessel, The example of described ohc-scr reactor figure 2 illustrates.In FIG, the discharge air-flow from exhaust manifold 17 passes through first row Go out gas duct portions 21 and reach oxidation catalyst 20.Oxidized discharge air-flow goes out gas duct portions 23 by second row and arrives Reach ohc-scr catalyst 24, then pass through the 3rd conduit portion 25.Discharging gas can be by the 3rd conduit portion 25 from discharge gas System system flows out.Discharge gas system 16 and may also include other devices-such as and be used for removing carbonaceous particles material from discharging air-flow Filter or catcher (not shown).
In this example, oxidizing hydrocarbons are reduced agent material (for example, ethanol) and spray into second by reducing agent material injectors 22 Discharge gas duct portions 23, the upstream of ohc-scr catalyst 24.Ohc-scr catalyst 24 can absorb ethanol or other oxidations Hydrocarbon reductant, and promote the no discharging in air-flow of reducing agent and flowingxThe reduction reaction of component and oxygen is with by noxGroup Divide and be reduced to nitrogen.Ohc-scr catalyst 24 is preferably supported on the catalyst of the silver particles on alumina particle.ohc- Scr catalyst 24 can be applied in combination with diesel particulate filter or be used with any other suitable tectonic association.
By noxReact from the no discharging removal gas with oxidizing hydrocarbons reducing agentxPercentage ratio be referred to as transformation efficiency Or noxConversion ratio.According to the present invention, noxConversion ratio is added to the discharge air-flow of ohc-scr catalyst 24 upstream with persistently determination The number of reducing agent be closely related.
It is used herein to determine that the practice of the reduction dosage being added to ohc-scr catalyst 24 employs one group and can be considered as Discharge the sensor of the part of gas system 16.Discharge gas system 16 and may include noxSensor 28 and 30 and temperature sensing Device (often thermocouple) 32,34 and 36.Discharge gas system 16 and also include oxygen sensor 38, this oxygen sensor 38 is also at this Play an important role in bright practice.One noxSensor 28 is located at the upstream of oxidation catalyst 20, and another noxSensor 30 downstreams being positioned ohc-scr catalyst 24.In other embodiments, noxSensor 28 is positioned oxidation catalyst 20 And ohc-scr catalyst 24 between.Temperature sensor be alternatively positioned at ohc-scr catalyst 24 inner side or near.At this In bright some practices, sense depositing of other components-such as ammonia in the downstream of the 3rd conduit portion 25, ohc-scr catalyst 24 It is being also likely to be useful.
noxSensor and oxygen sensor occur in different forms, and can use in different forms.They are often Electrochemical device, this electrochemical device is compared discharging air-flow with air or other reference materials.Their signal is by electromotor Control module or other computer based modules receive and use.And can by with other sensors signal-such as quality The control module of airflow sensor combination is using from noxSensor or the signal of oxygen sensor, are discharged in air-flow with obtaining Current noxConcentration or the useful value of oxygen concentration.
By this noxSensor 28 and 30 is respectively used to obtain the no of the upstream and downstream of ohc-scr catalyst 24xConcentration Measured value.In other words, noxSensor 28 and 30 is used for obtaining the no flowing in and out ohc-scr catalyst 24xMeasured value Or numerical value.Described noxSensor 28 and 30 produces the no corresponding to the correspondence position at themxThe letter of the numerical value of concentration (ppm) Number, described signal is referred to as noxinAnd noxout.
Temperature sensor 32,34 and 36 is positioned throughout the various positions discharging gas system 16.For example, as shown in figure 1, Temperature sensor 34 is positioned the downstream of oxidation catalyst 20 and the upstream of ohc-scr catalyst 24, and temperature sensor 36 is fixed Downstream positioned at ohc-scr catalyst 24.Temperature sensor 32 is positioned the upstream of oxidation catalyst 20.Temperature sensor 32, Each in 34 and 36 measures the temperature of the discharge gas in their corresponding positions, and exports one corresponding to measurement temperature The signal of degree.Described signal passes through temperature sensor 32,34 and 36 and exports, and is referred to as t in FIGa、tbAnd tc.
Engine control module (ecm) 40 controls the torque output of electromotor 12.In this function, ecm40 can receive From the signal of one or more sensors, described sensor includes MAPS (map), quality air Flow sensor (maf), TPS (tps), intake air temperature sensor (ias) and for electromotor operating The sensor of other engine running parameters controlling.In the practice of the invention, ecm40 also includes reducing agent interpolation control mould Block 42, described reducing agent adds the matter that control module 42 controls the oxidizing hydrocarbons reducing agent being sprayed by reducing agent material injectors 22 Amount flow rate.By this way, reducing agent adds control module 42 and controls the reduction agent material being supplied to ohc-scr catalyst 24 Amount.It is principle pre-programmed according to the present invention to manage the computer of the interpolation of reduction agent material that reducing agent adds control module 42 Element, described reduction agent material is used for the no discharging in air-flow contacting with ohc-scr catalyst 24 flowingxThe reduction of component. For example, reduction agent material can be stored in fuel tank or other suitable bins, and is conveyed by conduit (not shown) To reducing agent material injectors 22.
As schematically shown in FIG, reducing agent add control module 42 receive from temperature sensor, one or Multiple noxComponent sensor and the signal of at least one oxygen sensor.Except temperature sensor and discharge gas composition sensors, Also the upstream in ohc-scr catalyst 24 is provided with the sensor that gas mass flow rate is discharged in detection, and described sensor is used for leading to Cross module 42 to carry out discharging the lasting determination of gas volume flow rate, thus for the discharge gas contacting with ohc-scr catalyst 24 The calculating of the space velocity (or similar discharge gas volume) of body.For example, In some embodiments of the present invention, reducing agent Add control module to determine using the data of the quality air stream and The fuel stream that enter electromotor or estimate currently to discharge gas Body flow rate.
In FIG, reducing agent being sent to discharge air-flow is by arriving reducing agent in ohc-scr catalyst injected upstream Discharge air-flow to realize.The additive method of reducing agent transmission includes: 2) later stage in expansion stroke sprays into the electromotor of igniting Cylinder；3) it is ejected into the deactivated cylinder not lighting a fire and being not added with burning fuel；4) by close intake ＆ exhaust valves cylinder deactivation it Before be ejected in cylinder, in following cycle, then open air bleeding valve, to allow any reaction of reducing agent and reducing agent Product enters discharges gas system.In practice, oxidizing hydrocarbons are added by vehicle motor, thus preferably can reduce or Exempt the use discharging oxidation reactor in air-flow.
Persistently determine in description and be added to discharge air-flow for use in noxThe reducing agent of suitable quality of effective reduction Before method, first illustrate for containing noxAnd the discharge gas containing reducing agent through and described gas with to be placed on catalysis anti- The example answering the reactor (or container) of the effective contact of ohc-scr reducing catalyst 24 in device is helpful to.Fig. 2 illustrates Ohc-scr reactor 60.
Refering to Fig. 2, ohc-scr reactor 60 may include stainless pipe body 62, and described stainless pipe body 62 is used for tight Sealing-for example extrude, columned, favose cordierite catalyst supporter 64, described supporter 64 is in pipe body Visible in the section window of 62 sides.Supporter 64 can be suitable known to other pottery or metal material formed.Real at this Apply in mode, cordierite supporter 64 extends to downstream-urge by from the discharge gas access face 65 of upstream-catalyst support Multiple flow of exhaust circulation passage of discharge gas outlet face (invisible in fig. 2) of agent supporter are formed.These rills Circulation passage is represented as reticule in the diagram discharging gas access face 65.For example, during the extruding of ceramic body, in entrance Face is usually formed 400 circulation passages per square inch.The beaded catalyst of aluminium oxide overlying silver is coating in the form of coating On the wall of each passage of honeycomb texture.Steel body 62 compares discharge gas with the diameter of the silver-based reducing catalyst supporter 64 of sealing The upstream and downstream of body canal is big, to occupy the inlet face 65 of catalyst support 64 and flow through coating and lead to discharge air-flow Reduce the resistance discharging air-flow during road.Supporter 64 is sealed in steel body 62 and is directed to thus and supporter to discharge air-flow The ohc-scr catalyst contact supporting on 64 conduit wall.
As can be seen from Figure 2, the upstream end (as discharged shown in airflow direction arrow 66) of steel obturator 62 is by expanding The rustless steel of exhibition is discharged gas entrance part 68 and is sealed.The discharge gas access 70 of intake section 68 is dimensioned to and is suitable to connect Receive from discharge gas conduit 23(Fig. 1) discharge air-flow.Discharge gas entrance part 68 and be soldered to steel obturator 62.With similar Method, the downstream (discharge airflow direction arrow 72) of steel obturator 62 is shunk by mobile section, steel discharges gas portion Points 74 sealings, described steel is discharged gas part 74 and is had to be suitable to be soldered to downstream row and go out the discharge gas of gas conduit part and Mouth 76.
Temperature sensor (not shown in FIG. 2) can be positioned in steel obturator 62.For example, this sensor can position Upstream 65 and/or downstream in catalyst support 64.
Practice according to the present invention is it is necessary to obtain through the silver-colored selective reduction catalyst of aluminium oxide overlying containing noxRow Go out the measured value of the volume flow rate of air-flow.As shown in Fig. 2 discharge air-flow being separated in the inlet face 65 of catalyst support 64, Then pass through multiple very little passages, and the silver catalyst of coating granule form has been applied to described passage.In this embodiment party In formula, it is often preferred that outside, surface the volume volume as catalyst of supporter 64 is used.Thus, containing nox's The useful measured value with respect to coating, multichannel supporter space velocity discharging air-flow can be by being led to the air-flow containing discharge The external volume of the cordierite bodies in road to determine divided by the volumetric flow rate per hour discharging gas.For example, volumetric flow rate can be in row Go out and determine under the actual temperature of gas and the standard temperature and pressure (STP) of pressure or discharge gas.
In these are used for adding oxidizing hydrocarbons reducing agent to the operation strategy discharging air-flow, an important control becomes Amount is reductant concentration and the no of ohc-scr catalyst upstreamxThe ratio of concentration.As shown in figure 1, sensor is in given operation bar It is used for measuring no under partxConcentration, and appropriate reducing agent is introduced discharge gas.Reductant concentration is to be included in reducing agent The concentration with respect to nitrogen oxides carbon particulate concentrations representing, and c1(reducing agent will be designated)/noxRatio.Therefore, When ethanol is used as reducing agent material, in c1/noxIn ratio, 1 moles ethanol provides 2 moles of c1 reducing agents.
The stochastic process modeling added for the reducing agent of ohc-scr
The present inventor's here using stochastic process modeling (spm) provide discharge gas parameter and silver catalyst temperature it Between quantitative relation so that management is added to containing noxDischarge air-flow oxidizing hydrocarbons.Stochastic process modeling is advanced experience Modeling method, it enters row interpolation behaviour after regulation is present in for the noise in the data of tectonic model between data point Make.The spm instrument being used is based on matlab and is obtained from ricardo by power engineering experimental design (depe) group.
In an example using this modeling, during two different known diesel engines operation cycle, it is based on There is noxThe running engine data mining random process model of conversion: heavily loaded federal test program (hdftp) and additional discharge Test (set), it is also the United States Federal's test program.Determine and need the input data obtaining from experiment will be catalyst inlet temperature No at degree, catalyst inletx, the concentration of each in c1 hydro carbons (ethanol) and oxygen and the gas hourly space velocity passing through catalyst. Output variable is noxConversion ratio or the rear ohc-scr no of correlationxConcentration.
Tested with 6.6 liters of turbocharging type Diesel engines.Diesel oxidation catalyst group by exhaust manifold downstream In a row go out gas system, be followed by 10 liters of ag/al2o3Ohc-scr catalyst.Effluent air temp at the spray site of measurement During higher than 220 DEG C, ethanol is sprayed into the discharge gas system between oxidation catalyst and silver catalyst bed.Become with fast Fourier Change infrared spectroscopy (ftir) photometer and obtain the measured value discharging gaseous matter, and per second during each cycle of engine This measured value can be produced.
Operate in two federal tests circulate with electromotor, the test of electromotor produces thousand of data points.Use 164 data points are configured to the satisfactory model of hdftp, and this model is successfully implemented by engine control module Stochastic process modeling analysis, thus with Diesel engine similar with test loop or overlap circulation in operating and control Ethanol to concrete Diesel engine adds.However, for the summary providing the Example operating parameters in this test, will select Performance variable scope be arbitrarily divided into high temperature type and low temperature type.
For illustration purposes, the value of these performance variables is divided into low scope and high scope.The low scope of these variables is such as Shown in lower:
< 300 DEG C of temperature
noxConcentration < 200ppm
o2Concentration < 11%
Space velocity < 50000hr-1.
The high scope of these variables refers to more than the value of these upper limits of low scope.This packet leads to produce 16 examples Property operating condition, constitute the low value of 4 performance variables and 16 various combinations of high level.Because each exemplary operating bar Part represents the scope of a variate-value, it is achieved that maximum noxRequired c1 (the reducing agent)/no of conversionxRatio can also be one Scope.The maximum no of realization is shown in each in 16 exemplary operating conditionsxRequired c1 (the reducing agent)/no of conversionxThan The scope of rate.The stochastic process modeling having passed through to test, in hdftp and additional discharge, the engine data obtaining in (set) determines This scope.With ethanol as reducing agent, as shown in Table 1:
Form 1 is the operation strategy with ethanol as hc-ohc-scr reducing agent
Temperature nox Space velocity o2 C1 (ethanol)/nox
Low Low Low Low 2
Low Low Low High 2-40
Low Low High Low 2-3
Low Low High High 2
Low High Low Low 2-37
Low High Low High 1-2
Low High High Low 1-2
Low High High High 1-14
High Low Low Low 3-32
High Low Low High 1-40
High Low High Low 2-31
High Low High High 6-72
High High Low Low 9-12
High High Low High 7-23
High High High Low 4-26
High High High High 6-10
If engine data is comprehensive enough, under any desired engine operation condition, engine data is random Process model building all can provide desired c1/noxRatio.Each 3 to 5 in meeting height-substandard concrete electromotor shapes Under condition, form above is configured to using desired c1/noxThe stochastic modeling of ratio is predicted (by entering to engine data Row interpolation), here it is the reason provide scope.In actual practice, for the concrete engine condition of particle test program Quantity will must be determined using the random process model based on the engine data being used for this particle test program.
In other words, engine calibration will limit under such as federal test program using than 16 much more points of point Controllable engine condition, or other select, desired electromotor operation cycle.But once from for particle test journey Random process model is developed, then in test in the about 100-200 appropriate Engine Block Test service condition selecting of sequence During program, this model can be used in predicting desired c1/no under any operating conditionxRatio.Needed for particle test program Need predict operating condition quantity by based on need noxThe amount of reducing agent determines, avoids the need for onboard storing simultaneously Substantial amounts of reducing agent, and acceptable effective fuel economy penalty will not be exceeded due to the consumption of ethanol.
Thus, for real engine alignment purpose, will be true under each big and an appropriate number of difference operating condition Fixed preferred c1(ethanol)/noxRatio.Determine preferred c1(ethanol)/noxRatio factor to be considered, except limiting operating bar Outside four variables of part, also flow out the no of ohc-scr catalystxMass flowrate, other discharge gases of not being expected to The mass flowrate of composition-such as ammonia and the equivalent fuel economy penalty being caused to discharge gas by interpolation ethanol, described Discharge the by-product that gas componant is probably the operation of ohc-scr catalyst.In this embodiment, ethanol is vehicle-mounted and stores In the container of vehicle, described container is independent of normal fuel case, and uses in discharging gas system as needed.Also may be used According to described below using in requisition for reducing agent other devices.Use engine fuel can be diesel oil, gasoline, Hydrogen, natural gas, lpg, dimethylether or other suitable lean-combustion engine fuel.
Stochastic process modeling be also applied to from four-cylinder gasoline fuel, lean-burn operation, spark-ignition direct-injection (sidi) no in the aerofluxuss of electromotorxOhc-scr.(by volume, this fuel is referred to as ethanol and 85% ethanol, 15% gasoline E85 mixture) is used as ohc and reduces additive.When electromotor is in warming up pattern, electromotor is driven with new Europe and follows Ring operates, and in described warming up pattern, discharges gas and is in the temperature being suitable to effective silver catalyst function.Test sum Performed as describe above with reference to Diesel engine according to collection.Obtain thousand of data points and be used for electromotor operation cycle.Equally, It is developed for the appropriate model of driving cycle with hundreds of data point, this hundreds of data point is by engine control module The stochastic process modeling analysis implemented, for controlling when petrol engine is with or cycle operation that is overlapping similar with test loop Ethanol is to specifically petrolic interpolation.
As the reducing agent of ohc-scr, the advantage of ethanol or other effective oxides can be in the discharge gas of electromotor Realize, described electromotor is designed to be run with any fuel-alcohol mixture or any fuel-oxygen compound mixture.Rear In the case of one, reducing agent can be conveniently used the source as ohc-scr reducing agent for the receiving material of fuel tank.Effective oxygen in fuel The concentration of compound is bigger, attainable noxThe improvement of conversion ratio is bigger.If necessary, aoxidizing before spraying into discharge gas Thing can be separated with fuel so that the reducing agent that its concentration is improved and is sparged into is more effective.This separation can use film to realize, uses Water or other suitable chemical substance extraction are realized or are realized using other suitable methods.With journey similar as mentioned above Sequence can be used for being developed for the operation strategy of any engine fuel-oxide mixture.

Claims (10)

1. a kind of method determining that oxidizing hydrocarbons reduce the addition of agent material, described reduction agent material is used for next free lean-burn and sends out The no discharging in gas of the vehicle that motivation drivesxThe catalyst of component promotes reduction；Described vehicle motor includes multiple combustions Burn cylinder and connecting to the exhaust manifold of described cylinder, in described combustion cylinders fuel and air be mixed and light so that Reciprocating piston in driving cylinder, in described exhaust manifold be derived from cylinder combustion product be combined into including oxygen gas and water, Nitrogen and noxDischarge air-flow continuous part；And described vehicle includes discharging gas conduit, described discharge gas conduit is used In flow conductance will be discharged to reactor to contact with the silver/aluminium oxide catalyst being included in described reactor, thus leading to Cross and react with the oxidizing hydrocarbons reducing agent being added and make noxThere is electronation in component；When vehicle operation and produce discharge gas During stream, methods described includes；
Before the reactor that air-flow enters containing reducing catalyst, (a) utilizes oxygen sensor test constantly just in reduction catalystses The oxygen content of a part of discharge air-flow of agent upstream and (b) utilize noxSensor test constantly discharges a part for air-flow NoxContent；
Test constantly (c) contains the temperature of the reducing catalyst in the reactor of reducing catalyst；
The gas hourly space velocity of the discharge air-flow that test constantly (d) is contacted with reducing catalyst flowing；And using at least four measurements Value (a-d):
Persistently determine the amount of reduction agent material, so that the no being reduced by silver catalystxAmount maximizes, and described reduction agent material exists Discharge before air-flow enters reduction reactor and be added to the current portions discharging air-flow, described determination uses pre-programmed, car Carry computer and carried out using four at least current measured values；And
Discharging air current flow to before contact with reducing catalyst, the amount of the current determination of reducing agent is being added to discharge gas Stream.
2. the method determining that oxidizing hydrocarbons reduce the addition of agent material as claimed in claim 1, wherein reduces agent material bag Include the alcohol selected from the set of following every compositions: methanol, ethanol, the aldehyde of propanol, butanol or such alcohol.
3. the method determining that oxidizing hydrocarbons reduce the addition of agent material as claimed in claim 1, wherein reduces agent material bag Include ethanol.
4. the method determining that oxidizing hydrocarbons reduce the addition of agent material as claimed in claim 1, wherein reducing catalyst bag Include the Argent grain being supported on alumina particle.
5. the method determining that oxidizing hydrocarbons reduce the addition of agent material as claimed in claim 1, wherein reduction agent material It is added in the discharge gas conduit of reducing catalyst upstream and carry out.
6. the method determining that oxidizing hydrocarbons reduce the addition of agent material as claimed in claim 1, wherein adds reducing agent material Material is in the combustion product injecting it in cylinder, and then it enters exhaust manifold and discharges gas conduit.
7. the method determining that oxidizing hydrocarbons reduce the addition of agent material as claimed in claim 1, wherein reduces agent material quilt Add to cylinder, and enter exhaust manifold from cylinder in the case of the reduction agent material that need not burn.
8. the method determining that oxidizing hydrocarbons reduce the addition of agent material as claimed in claim 1, wherein vehicle motor Fuel is one or more material selected from the set of following every compositions: diesel oil, gasoline, hydrogen, natural gas, liquefaction stone Oil gas, ethanol, methanol and dimethylether.
9. the method determining that oxidizing hydrocarbons reduce the addition of agent material as claimed in claim 1, is wherein added to discharge gas The lasting determination of the amount of reduction agent material of stream is included by car-mounted computer Lai with reference to the selected scope for four measured values The predetermined of addition of selected reduction agent material table look-up.
10. the method determining that oxidizing hydrocarbons reduce the addition of agent material as claimed in claim 9, wherein reducing agent material is Ethanol, and be added to discharge air-flow the amount of ethanol lasting determination include by car-mounted computer come with reference to for four surveys The predetermined of the addition of the ethanol of selected scope of value tables look-up.
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Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102806012B (en) 2011-06-03 2016-11-23 通用汽车环球科技运作有限责任公司 For NO is oxidized to NO2non-stoichiometric perovskite oxide oxidation catalyst
US8920756B2 (en) 2012-05-07 2014-12-30 GM Global Technology Operations LLC Silver promoted close-coupled NOx absorber
DE102014207641A1 (en) 2014-04-23 2015-10-29 Siemens Aktiengesellschaft Process for exhaust aftertreatment and combustion system
DE102014014595A1 (en) * 2014-10-07 2016-04-07 Man Truck & Bus Ag Method and device for operating a vehicle, in particular a utility vehicle
KR101903406B1 (en) 2015-02-16 2018-11-07 삼성중공업 주식회사 Device for Purifying Exhaust and Vessel having the Same
US11199162B2 (en) 2016-01-19 2021-12-14 Eaton Intelligent Power Limited In-cylinder EGR and VVA for aftertreatment temperature control
US10801430B2 (en) * 2016-01-19 2020-10-13 Eaton Intelligent Power Limited In-cylinder EGR for air fuel ratio control
JP6521908B2 (en) * 2016-07-04 2019-05-29 中外炉工業株式会社 Industrial furnace
US10288017B1 (en) * 2017-10-25 2019-05-14 GM Global Technology Operations LLC Model based control to manage eDOC temperature
CN108590816B (en) * 2018-03-02 2023-04-28 天津大学 Method and system for selectively catalyzing and reducing NOx by using methanol as reducing agent
CN113614339B (en) * 2019-03-14 2023-10-27 康明斯有限公司 Diesel engine exhaust fluid doser protection using cylinder cut-off method under cold ambient temperature conditions
WO2020205112A1 (en) * 2019-03-29 2020-10-08 Cummins Emission Solutions Inc. Systems and methods for determining amount of reductant deposits in aftertreatment systems
WO2021102680A1 (en) * 2019-11-26 2021-06-03 天津大学 Diesel-methanol combined combustion engine and control method therefor
CN112664298A (en) * 2020-06-16 2021-04-16 长城汽车股份有限公司 Exhaust gas purification system for vehicle and exhaust gas purification method for vehicle
CN111841301B (en) * 2020-07-23 2022-03-11 赵莉莉 Garbage deodorization method and system
CN113513393A (en) * 2021-04-24 2021-10-19 王德仓 Engine emission reduction device for monitoring concentration of NOx in real time and adjusting hydrogen and oxygen content

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101219339A (en) * 2006-09-20 2008-07-16 通用汽车环球科技运作公司 Method and apparatus to selectively reduce NOx in an exhaust gas feedstream

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3440290B2 (en) * 1993-08-26 2003-08-25 独立行政法人産業技術総合研究所 Exhaust gas purification method
ATE369486T1 (en) * 2004-12-18 2007-08-15 Haldor Topsoe As METHOD FOR CONTROLLING THE ADDITION OF A REDUCING AGENT INTO THE EXHAUST GAS OF AN INTERNAL COMBUSTION ENGINE
US7877986B2 (en) * 2007-05-04 2011-02-01 GM Global Technology Operations LLC Method and apparatus for generating a reductant in an exhaust gas of a compression-ignition engine

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101219339A (en) * 2006-09-20 2008-07-16 通用汽车环球科技运作公司 Method and apparatus to selectively reduce NOx in an exhaust gas feedstream

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