US20140338311A1 - Method for operating a dosing apparatus and motor vehicle having a dosing apparatus - Google Patents

Method for operating a dosing apparatus and motor vehicle having a dosing apparatus Download PDF

Info

Publication number
US20140338311A1
US20140338311A1 US14/450,423 US201414450423A US2014338311A1 US 20140338311 A1 US20140338311 A1 US 20140338311A1 US 201414450423 A US201414450423 A US 201414450423A US 2014338311 A1 US2014338311 A1 US 2014338311A1
Authority
US
United States
Prior art keywords
pressure
dosing
pressure accumulator
valve
pump
Prior art date
Legal status (The legal status 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 status listed.)
Abandoned
Application number
US14/450,423
Other languages
English (en)
Inventor
Rolf Brueck
Jan Hodgson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vitesco Technologies Lohmar Verwaltungs GmbH
Original Assignee
Emitec Gesellschaft fuer Emissionstechnologie mbH
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 Emitec Gesellschaft fuer Emissionstechnologie mbH filed Critical Emitec Gesellschaft fuer Emissionstechnologie mbH
Assigned to EMITEC GESELLSCHAFT FUER EMISSIONSTECHNOLOGIE MBH reassignment EMITEC GESELLSCHAFT FUER EMISSIONSTECHNOLOGIE MBH ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: BRUECK, ROLF, HODGSON, JAN
Publication of US20140338311A1 publication Critical patent/US20140338311A1/en
Abandoned legal-status Critical Current

Links

Images

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
    • 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
    • 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
    • F01N3/206—Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents
    • F01N3/208—Control of selective catalytic reduction [SCR], e.g. by adjusting the 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
    • 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
    • F01N3/206—Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents
    • F01N3/2066—Selective catalytic reduction [SCR]
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
    • F01N3/36—Arrangements for supply of additional fuel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/01—Adding substances to exhaust gases the substance being catalytic material in liquid 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
    • 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
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/14—Arrangements for the supply of substances, e.g. conduits
    • F01N2610/1446—Means for damping of pressure fluctuations in the delivery system, e.g. by puffer volumes or throttling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/14—Arrangements for the supply of substances, e.g. conduits
    • F01N2610/1473—Overflow or return means for the substances, e.g. conduits or valves for the return path
    • 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
    • F01N2900/1806—Properties of reducing agent or dosing system
    • F01N2900/1808—Pressure
    • 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

Definitions

  • the invention relates to a method for operating a dosing or metering apparatus for providing a liquid additive.
  • the dosing apparatus may, for example, be utilized for feeding a liquid additive into an exhaust-gas treatment apparatus, where the liquid additive is used for the purification of the exhaust gases of a mobile internal combustion engine (in particular in a motor vehicle).
  • the invention also relates to a motor vehicle having a dosing or metering apparatus.
  • Exhaust-gas treatment apparatuses into which a liquid additive is fed have become increasingly widely used in recent times.
  • An exhaust-gas purification method particularly commonly implemented in such exhaust-gas treatment apparatuses is the selective catalytic reduction (SCR) method in which nitrogen oxide compounds in the exhaust gas are reduced with the aid of a reducing agent.
  • the reducing agent is generally fed to the exhaust-gas treatment apparatus in the form of a liquid additive.
  • a liquid additive particularly commonly used in this context is urea-water solution.
  • a urea-water solution with a urea content of 32.5% is available under the trademaek AdBlue® and is widely used.
  • the urea-water solution is merely a reducing agent precursor and is converted into ammonia (the reducing agent) outside the exhaust gas (in a reactor provided for that purpose) or in the exhaust gas (in the exhaust-gas treatment apparatus, under the action of the exhaust gas). Nitrogen oxide compounds in the exhaust gas are then, together with the ammonia, reduced in the presence of an SCR catalytic converter to form non-hazardous substances (water, CO 2 and nitrogen).
  • the invention is used in this technical field in particular.
  • the dosing apparatus for providing a liquid additive should be of the simplest possible construction and should be as durable, maintenance-free and inexpensive as possible. At the same time, it is desirable for the dosing accuracy of a dosing apparatus to be particularly high. In this way, it is possible firstly for the amount of liquid additive required for the conversion of pollutant constituents in the exhaust gas to be set in a particularly exact manner. It is furthermore possible for overdosing to be prevented in an effective manner.
  • a method for operating a dosing apparatus for providing a liquid additive, in particular urea-water solution comprising at least the following steps:
  • the dosing apparatus particularly preferably serves for the dosing of a reducing agent (or of a reducing agent precursor such as urea-water solution) as a liquid additive into an exhaust-gas treatment apparatus of an internal combustion engine.
  • the pump is preferably a diaphragm pump or a piston pump.
  • the delivery rate of the pump is preferably not regulated. This means that an electronic regulator or controller, through the use of which the flow rate of additive delivered by the pump can be exactly set, is not provided.
  • the tank is preferably connected to the pump through a suction line through which the pump can draw liquid additive out of the tank.
  • the pressure accumulator is preferably disposed downstream of the pump as viewed in a flow direction of the liquid additive from the tank to the dosing valve.
  • the pressure accumulator may, for example, be in the form of a flexible line that expands when liquid additive is delivered into the flexible line under pressure by the pump.
  • the dosing valve is preferably an electrically controlled solenoid valve that can be opened and closed by the electric drive, wherein the opening time of the dosing valve predefines the amount of liquid additive provided.
  • the pressure accumulator is also adjoined by a return valve. The return valve is preferably connected back to the tank through a return line in order to ensure that liquid additive present in the pressure accumulator can be discharged back into the tank.
  • the identification of a dosing demand in step a) preferably involves the identification of an electronic signal from an engine controller, which electronic signal is representative of a dosing demand.
  • an engine controller transmits a signal that corresponds to a certain flow rate of liquid additive required.
  • the signal is detected, or identified, as a dosing demand.
  • step a) it is preferably the case that a pressure prevailing in the pressure accumulator is so low that handling of the dosing demand is not possible. It is preferably the case that, during step a), the pressure in the pressure accumulator is lower than 2 bar, particularly preferably lower than 1 bar and very particularly preferably lower than 0.5 bar.
  • step b) the pump is activated in order to build up a pressure in the pressure accumulator that is required in order to ensure that suitable dosing can be performed by using the dosing valve.
  • a diaphragm pump or a piston pump is preferably operated with between 2 and 10 pump strokes.
  • the number of pump strokes required to build up the required pressure in the pressure accumulator is dependent on the flexibility of the pressure accumulator and on the pressure difference between the pressure during step a) and the dosing pressure (step b).
  • the more flexible the pressure accumulator the more liquid additive can be delivered into the pressure accumulator in order for the required pressure to be built up.
  • the greater the pressure difference the more liquid additive can be delivered into the pressure accumulator.
  • the pressure built up as a result of the activation of the pump in step b) is preferably between 3 and 10 bar, particular preferably between 5 and 10 bar and very particularly preferably between 6 and 8 bar.
  • the pressure built up by the pump in step b) is typically slightly higher than the dosing pressure required in order to be able to perform precise dosing by using the dosing valve. The reason for this is that the pump is preferably unregulated. This means that the pump is not deactivated when a certain pressure is attained, and instead, the pump, after being activated, initially continues running regardless of the magnitude of the pressure prevailing in the pressure accumulator, which pressure acts counter to the pump.
  • the operation of the pump ends only when the pressure in the pressure accumulator is so high that the pump can generate no further pressure increase in the pressure accumulator.
  • method steps a) to d) are performed repeatedly during the operation of the dosing apparatus.
  • the pressure in order to set the pressure in step c), the pressure is reduced, in particular by virtue of the return valve being opened. It is thus preferably provided that, in order to set a precise pressure in the pressure accumulator that is desired for being able to perform very precise dosing by using the dosing valve, the return valve is opened.
  • step b) continues to take place during step c).
  • the return valve remains open and the pump is activated. Due to a return flow of liquid additive through the return valve, the pressure in the pressure accumulator remains constant.
  • steps c) and d) are performed at least partially in parallel with one another. It is particularly preferable even for steps b), c) and d) to take place at least partially in parallel (at the same time).
  • the dosing valve is opened for the dispensing of the liquid additive through the dosing valve in step d).
  • Liquid additive then flows out of the pressure accumulator through the dosing valve to a consumer for the liquid additive.
  • the consumer for the liquid additive is preferably an exhaust-gas treatment apparatus in which the method of selective catalytic reduction is performed using the liquid additive. It is preferably the case that method steps b) and c) continue to take place during the execution of step d).
  • the pump remains activated and continues to deliver liquid additive into the pressure accumulator.
  • the return valve remains open and ensures that the pressure in the pressure accumulator is set to the dosing pressure, required for the dosing action, of for example a value between 5 and 10 bar, for example 7 bar.
  • the return valve is preferably not open at all times, and is instead opened in pressure-controlled fashion every time the pressure in the pressure accumulator exceeds the dosing pressure. In this way, the pressure in the pressure accumulator is in each case repeatedly regulated to the dosing pressure during the dispensing of the additive through the dosing valve.
  • step d It is not necessary for the dosing valve to be open continuously for dispensing the additive in step d). It is also possible for the dosing demand identified in step a) to be dispensed in several pulses. In this case, a pulse corresponds in each case to one opening process and one closing process of the dosing valve.
  • the pump is deactivated after method step d) in each case.
  • the pump is then reactivated only when a new dosing demand is identified in a new step a).
  • the pump does not run continuously during the operation of a delivery line and of a motor vehicle in which the dosing apparatus is disposed, and instead, the pump is generally activated only when a dosing demand is present.
  • a step e) of lowering the pressure in the pressure accumulator is performed after method step d).
  • Method step e) is preferably also performed repeatedly together with method steps a) to d).
  • the pressure accumulator may be actively relieved of load.
  • a return valve that branches off from the pressure accumulator may, if appropriate, be actively opened in step e) in order to permit an escape of the liquid additive from the pressure accumulator and thus ensure a lowering of the pressure in the pressure accumulator.
  • the return valve may be identical to the return valve used in step c) of the method, and may be additionally capable of being actively opened in step e). It may, however, also be provided that, for step e), an additional return valve is provided which can be actively opened and which is disposed preferably in a parallel second return line from the pressure accumulator to the tank.
  • step e) the pump may, if appropriate, be operated counter to the delivery direction in order to deliver liquid additive out of the pressure accumulator and back into the tank in order that the pressure in the pressure accumulator decreases and the pressure accumulator is thus relieved of load.
  • the pressure accumulator prefferably be passively relieved of load.
  • a leakage flow of liquid additive to flow back into the tank through a return valve and/or through the pump in step e), this resulting in a lowering of the pressure in the pressure accumulator.
  • the pressure in the pressure accumulator falls relatively slowly because the leakage flow is generally relatively small. The effect of the leakage flow on the pressure in the pressure accumulator during the dosing in step d) would otherwise be too great.
  • the return valve is a passively opening valve, the opening pressure of which corresponds to the dosing pressure.
  • the return valve is preferably a passively opening valve which opens at a predetermined or preset threshold pressure, wherein the threshold pressure corresponds to the dosing pressure (the pressure with which the additive is dosed).
  • the return valve preferably has a valve body and a valve spring which exerts a preload on the valve body. The return valve opens when the force exerted on the return valve by the liquid additive present in the pressure accumulator exceeds the spring force of the spring in the return valve.
  • the dosing apparatus can be implemented without an electrically driven dosing valve and/or without an (active) control unit of the return valve.
  • the return valve is an actively opening valve with a valve drive, wherein a pressure sensor is disposed on the pressure accumulator and the return valve is controlled, with the aid of the valve drive, by a control unit in order to set the pressure in the pressure accumulator to the desired dosing pressure in step c).
  • the valve drive may, for example, be an electromagnet which exerts a force on an armature in the return valve, through the use of which force the return valve can be opened and/or closed.
  • the pressure sensor may, for example, be in the form of an electronic pressure sensor which measures a pressure in the pressure accumulator and transmits it as an electrical signal to the control unit. The pressure information is then processed in the control unit in order to specify whether the check or return valve is to be opened and/or closed (regulating loop).
  • the pump has a pump chamber and at least one pump valve which predefines a delivery direction.
  • the pump chamber preferably has a pump movement imparted to it by a diaphragm or a pump piston.
  • two pump valves are provided each of which has a passively opening configuration and is respectively disposed upstream or downstream of the pump chamber as viewed in the flow direction of the liquid additive from the tank to the dosing valve.
  • only a single pump valve is provided.
  • the single pump valve is then preferably provided downstream of the pump chamber as viewed in the flow direction.
  • the pump piston is then constructed in such a way that, during a delivery movement (discharge movement), it discharges the liquid additive in the pump chamber through the pump valve. A replenishment flow of liquid additive into the pump chamber then takes place during a return movement of the pump piston directed counter to the delivery movement.
  • a pump of that type is described, for example, in German Patent DE 10 2008 010 073 B4, in particular in FIGS. 2 and 3 and in the explanations with regard thereto in paragraphs [0038] to [0051], the entire content of which is incorporated herein.
  • the method according to the invention is used, in particular, in the case of a dosing apparatus that preferably does not have a pressure sensor on the pressure accumulator for electronically monitoring the pressure in the pressure accumulator.
  • the pressure in the pressure accumulator is set exclusively by using the return valve.
  • the return valve preferably acts mechanically.
  • a motor vehicle comprising an internal combustion engine, an exhaust-gas treatment apparatus for purifying exhaust gases of the internal combustion engine and a dosing apparatus through which a liquid additive can be fed to the exhaust-gas treatment apparatus and which is set up and constructed for operation in accordance with the described method.
  • the motor vehicle is preferably a passenger motor vehicle or a truck.
  • the internal combustion engine is preferably a diesel internal combustion engine.
  • the exhaust-gas treatment apparatus preferably has an SCR catalytic converter for carrying out the method of selective catalytic reduction.
  • the exhaust-gas treatment apparatus is preferably fed with reducing agent, and in particular urea-water solution as a liquid additive, upstream of the SCR catalytic converter. Then, the method of selective catalytic reduction is performed with the reducing agent in the exhaust-gas treatment apparatus for the purpose of reducing nitrogen oxide compounds in the exhaust gas in an effective manner.
  • FIG. 1 is a block diagram of a dosing apparatus together with a tank and an exhaust-gas treatment apparatus;
  • FIG. 2 is a block diagram of a further structural variant of a dosing apparatus together with a tank and an exhaust-gas treatment apparatus;
  • FIG. 3 is a block diagram of a motor vehicle having a dosing apparatus
  • FIG. 4 is a first diagram showing a sequence of the method according to the invention.
  • FIG. 5 is a second diagram showing the sequence of the method according to the invention.
  • FIG. 1 there is seen a dosing apparatus 1 together with a tank 3 and an exhaust-gas treatment apparatus 11 .
  • the dosing apparatus 1 extracts liquid additive (urea-water solution) from the tank 3 at an extraction point 17 .
  • a delivery line 18 which extends from the extraction point 17 runs initially to a pump 2 .
  • the pump 2 has a pump chamber 22 and at least one pump valve 23 predefining a delivery direction 24 .
  • the pump chamber 22 has a diaphragm or a pump piston and may have only one valve downstream of the pump chamber, as described further above.
  • the delivery line 18 extends from the pump 2 onward to a dosing valve 5 , through which the liquid additive can be fed into an exhaust-gas flow 13 in the exhaust-gas treatment apparatus 11 .
  • the liquid additive is delivered from the tank 3 through the delivery line 18 to the dosing valve 5 due to the delivery action of the pump 2 .
  • a pressure accumulator 4 is situated downstream of the pump 2 , as viewed in the delivery direction from the tank 3 to the dosing valve 5 .
  • the pressure accumulator 4 may be formed in part by the delivery line 18 , for example by virtue of the delivery line 18 being in the form of a flexible hose.
  • a return line 12 branches off from the pressure accumulator 4 and leads back into the tank 3 .
  • a return valve 6 is disposed in the return line 12 .
  • the structural variant of a dosing apparatus according to FIG. 2 corresponds, for the most part, to the structural variant according to FIG. 1 .
  • a valve drive 19 with which the return valve 6 can be opened and closed, is additionally provided in this case.
  • the pressure accumulator 4 is adjoined by a pressure sensor 20 with which the pressure in the pressure accumulator 4 can be measured.
  • the pressure information determined by using the pressure sensor 20 is passed to a control unit or controller 21 and processed therein.
  • the control unit 21 can open and close the return valve 6 as required by using the valve drive 19 .
  • FIG. 3 shows a motor vehicle 9 having an internal combustion engine 10 and an exhaust-gas treatment apparatus 11 with which the exhaust gases of the internal combustion engine 10 can be purified.
  • the exhaust gases of the internal combustion engine 10 flow, as an exhaust-gas flow 13 , through the exhaust-gas treatment apparatus 11 .
  • a liquid additive can be fed to the exhaust-gas treatment apparatus 11 through a dosing valve 5 provided on the exhaust-gas treatment apparatus 11 .
  • the liquid additive is supplied from a tank 3 to the dosing valve 5 by a dosing apparatus 1 .
  • FIG. 4 shows a first flow diagram of the method according to the invention.
  • a time axis 14 and a pressure axis 15 of the diagram can be seen.
  • a pressure profile 16 which occurs during the method according to the invention is plotted against the time axis 14 .
  • the pressure profile 16 is representative of the pressure in the pressure accumulator of the described dosing apparatus.
  • the pressure in the pressure accumulator is at a low constant rest pressure level, which is for example less than 2 bar.
  • a dosing demand is identified. If a dosing demand has been identified, then in step b), the pressure in the pressure accumulator is increased, as described further above, by activation of the pump.
  • the pressure profile 16 rises sharply.
  • step b) the pressure is, in part, increased to such an extent that it exceeds a dosing pressure 8 .
  • the pressure is set to the dosing pressure 8 by opening the return valve in step c), as described further above.
  • step d) dispensing of the liquid additive is performed through the dosing valve, with the liquid additive being at the dosing pressure 8 .
  • step e) is performed, in which the pressure in the pressure accumulator falls again.
  • the pressure profile 16 is preferably reduced to a rest pressure 7 from step a) again.
  • An active execution of step e) (for example by an active opening of a return valve, or a return delivery action by the pump) is not required. It is also adequate if, in step e), the pressure falls passively (for example due to a leakage flow through a return valve or through the pump).
  • FIG. 5 illustrates the method steps a), b), c), d) and e). It can be seen that the method steps are performed repeatedly at regular intervals in the manner of a loop.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Accessories For Mixers (AREA)
US14/450,423 2012-02-03 2014-08-04 Method for operating a dosing apparatus and motor vehicle having a dosing apparatus Abandoned US20140338311A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE102012002059.7 2012-02-03
DE102012002059A DE102012002059A1 (de) 2012-02-03 2012-02-03 Verfahren zum Betrieb einer Dosiervorrichtung
PCT/EP2013/052044 WO2013113882A2 (de) 2012-02-03 2013-02-01 Verfahren zum betrieb einer dosiervorrichtung

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2013/052044 Continuation WO2013113882A2 (de) 2012-02-03 2013-02-01 Verfahren zum betrieb einer dosiervorrichtung

Publications (1)

Publication Number Publication Date
US20140338311A1 true US20140338311A1 (en) 2014-11-20

Family

ID=47678778

Family Applications (1)

Application Number Title Priority Date Filing Date
US14/450,423 Abandoned US20140338311A1 (en) 2012-02-03 2014-08-04 Method for operating a dosing apparatus and motor vehicle having a dosing apparatus

Country Status (9)

Country Link
US (1) US20140338311A1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
EP (1) EP2809898A2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
JP (1) JP2015507125A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
KR (1) KR101719403B1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
CN (1) CN104093946A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
DE (1) DE102012002059A1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
IN (1) IN2014DN06574A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
RU (1) RU2595705C2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
WO (1) WO2013113882A2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019156690A1 (en) * 2018-02-12 2019-08-15 Cummins Emission Solutions Inc. Reductant insertion assembly comprising a bladder
US20230074405A1 (en) * 2020-02-17 2023-03-09 Vitesco Technologies GmbH Method for measuring a liquid flow rate at the outlet of a pump

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102020117216A1 (de) * 2020-06-30 2021-12-30 Fresenius Medical Care Deutschland Gmbh Verfahren und Vorrichtung zum Dosieren von Lösungen
DE102021121029B4 (de) 2021-08-12 2024-07-18 Volkswagen Aktiengesellschaft Verbrennungsmotor und Verfahren zur Dosierung eines Reduktionsmittels in die Abgasanlage eines Verbrennungsmotors

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000079108A1 (de) * 1999-06-22 2000-12-28 Robert Bosch Gmbh Vorrichtung zur dosierung eines reduktionsmittels
US6209315B1 (en) * 1998-04-30 2001-04-03 Siemens Akteingesellschaft Method and device for exhaust gas after-treatment in an internal combustion engine equipped with an SCR catalyst
DE10324482A1 (de) * 2003-05-30 2004-12-16 Robert Bosch Gmbh Vorrichtung zur Dosierung eines Reduktionsmittels zum Abgas eines Verbrennungsmotors
JP2005307769A (ja) * 2004-04-19 2005-11-04 Hino Motors Ltd 排気浄化装置
US20070186543A1 (en) * 2004-10-13 2007-08-16 Leo Bakaj Arrangement for the dosed injection of a reducing medium into the exhaust tract of an internal combustion engine
US20080148716A1 (en) * 2006-12-20 2008-06-26 Aisan Kogyo Kabushiki Kaisha Exhaust gas purification device of internal combustion engine
US20080276601A1 (en) * 2006-06-26 2008-11-13 Nissan Diesel Motor Co., Ltd Exhaust emission purifying apparatus for engine
US20100005871A1 (en) * 2007-01-26 2010-01-14 Eiichi Kitazawa Clogging Determining Device For Reducing Agent Injection Valve and Clogging Determining Method For Reducing Agent Injection Valve
US20100071349A1 (en) * 2007-02-19 2010-03-25 Eiichi Kitazawa Clogging determining device for reducing agent passage and clogging determining method for reducing agent passage
US20100115932A1 (en) * 2008-01-22 2010-05-13 Armin Kassel Metering system
US20100139245A1 (en) * 2006-12-13 2010-06-10 Johannes Scheuerer Method For Calibrating A Lambda Sensor And Internal Combustion Engine
US20110047996A1 (en) * 2008-03-10 2011-03-03 Ignacio Garcia-Lorenzana Merino Exhaust gas treatment apparatus with improved pressure pulse damping
US20110179772A1 (en) * 2008-09-26 2011-07-28 Daimler Ag Motor Vehicle Having a System for Feeding Fluid into Another Medium, Particularly for Feeding a Reducing Agent into the Exhaust Gas of an Internal Combustion Engine
US20130036724A1 (en) * 2011-08-12 2013-02-14 Emitec Gesellschaft Fuer Emissionstechnologie Mbh Method for metering a reducing agent, method for setting up a control unit for a metering device and motor vehicle having a metering device
US20130251546A1 (en) * 2012-03-20 2013-09-26 Robert Bosch Gmbh Method and control unit for metering fuel into an exhaust gas duct

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0712660Y2 (ja) * 1990-04-10 1995-03-29 日野自動車工業株式会社 ディーゼル・エンジンに使用される排気浄化装置
DE19947197A1 (de) * 1999-10-01 2001-04-12 Bosch Gmbh Robert Vorrichtung und Verfahren zur Dosierung eines Reduktionsmittels
DE10127834A1 (de) * 2001-06-08 2002-12-12 Bosch Gmbh Robert Vorrichtung und Verfahren zur Dosierung eines Reduktionsmittels zur Entfernung von Stickoxiden aus Abgasen
US6941746B2 (en) * 2002-11-21 2005-09-13 Combustion Components Associates, Inc. Mobile diesel selective catalytic reduction systems and methods
ATE411468T1 (de) * 2002-12-23 2008-10-15 Grundfos Nonox As Dosierpumpenaggregat
DE10346220A1 (de) * 2003-09-23 2005-04-14 Robert Bosch Gmbh Brennkraftmaschine mit Abgasnachbehandlungssystem
DE102004046881A1 (de) * 2004-09-28 2006-04-13 Robert Bosch Gmbh Zuführsystem für ein Medium, insbesondere zur Behandlung von Abgasen einer Brennkraftmaschine, Abgasreinigungsvorrichtung und Verfahren zum Betreiben eines Zuführsystems
AT500849B8 (de) * 2004-11-15 2007-02-15 Pankl Emission Control Systems Harnstoffdosiervorrichtung
DE102005002318A1 (de) * 2005-01-17 2006-07-27 Robert Bosch Gmbh Abgasnachbehandlungsverfahren und Vorrichtung hierzu
JP2008255948A (ja) * 2007-04-06 2008-10-23 Denso Corp 燃料噴射弁およびそれを用いた燃料噴射システム
DE102008010073B4 (de) 2008-02-19 2010-10-21 Thomas Magnete Gmbh System und Verfahren zum Dosieren eines Fluids
DE102009003101A1 (de) * 2009-05-14 2010-11-18 Robert Bosch Gmbh Antriebsaggregat sowie Verfahren zum Betreiben eines Antriebsaggregats
CN201924999U (zh) * 2010-11-30 2011-08-10 苏州派格力减排系统有限公司 尿素计量喷射泵自动标定系统

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6209315B1 (en) * 1998-04-30 2001-04-03 Siemens Akteingesellschaft Method and device for exhaust gas after-treatment in an internal combustion engine equipped with an SCR catalyst
WO2000079108A1 (de) * 1999-06-22 2000-12-28 Robert Bosch Gmbh Vorrichtung zur dosierung eines reduktionsmittels
DE10324482A1 (de) * 2003-05-30 2004-12-16 Robert Bosch Gmbh Vorrichtung zur Dosierung eines Reduktionsmittels zum Abgas eines Verbrennungsmotors
JP2005307769A (ja) * 2004-04-19 2005-11-04 Hino Motors Ltd 排気浄化装置
US20070186543A1 (en) * 2004-10-13 2007-08-16 Leo Bakaj Arrangement for the dosed injection of a reducing medium into the exhaust tract of an internal combustion engine
US20080276601A1 (en) * 2006-06-26 2008-11-13 Nissan Diesel Motor Co., Ltd Exhaust emission purifying apparatus for engine
US20100139245A1 (en) * 2006-12-13 2010-06-10 Johannes Scheuerer Method For Calibrating A Lambda Sensor And Internal Combustion Engine
US20080148716A1 (en) * 2006-12-20 2008-06-26 Aisan Kogyo Kabushiki Kaisha Exhaust gas purification device of internal combustion engine
US20100005871A1 (en) * 2007-01-26 2010-01-14 Eiichi Kitazawa Clogging Determining Device For Reducing Agent Injection Valve and Clogging Determining Method For Reducing Agent Injection Valve
US20100071349A1 (en) * 2007-02-19 2010-03-25 Eiichi Kitazawa Clogging determining device for reducing agent passage and clogging determining method for reducing agent passage
US20100115932A1 (en) * 2008-01-22 2010-05-13 Armin Kassel Metering system
US20110047996A1 (en) * 2008-03-10 2011-03-03 Ignacio Garcia-Lorenzana Merino Exhaust gas treatment apparatus with improved pressure pulse damping
US20110179772A1 (en) * 2008-09-26 2011-07-28 Daimler Ag Motor Vehicle Having a System for Feeding Fluid into Another Medium, Particularly for Feeding a Reducing Agent into the Exhaust Gas of an Internal Combustion Engine
US20130036724A1 (en) * 2011-08-12 2013-02-14 Emitec Gesellschaft Fuer Emissionstechnologie Mbh Method for metering a reducing agent, method for setting up a control unit for a metering device and motor vehicle having a metering device
US20130251546A1 (en) * 2012-03-20 2013-09-26 Robert Bosch Gmbh Method and control unit for metering fuel into an exhaust gas duct

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019156690A1 (en) * 2018-02-12 2019-08-15 Cummins Emission Solutions Inc. Reductant insertion assembly comprising a bladder
US11028752B2 (en) 2018-02-12 2021-06-08 Cummins Emission Solutions Inc. Reductant insertion assembly comprising a bladder
US20230074405A1 (en) * 2020-02-17 2023-03-09 Vitesco Technologies GmbH Method for measuring a liquid flow rate at the outlet of a pump
US12222229B2 (en) * 2020-02-17 2025-02-11 Vitesco Technologies GmbH Method for measuring a liquid flow rate at the outlet of a pump

Also Published As

Publication number Publication date
WO2013113882A2 (de) 2013-08-08
KR20140115351A (ko) 2014-09-30
EP2809898A2 (de) 2014-12-10
IN2014DN06574A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 2015-05-22
KR101719403B1 (ko) 2017-03-23
WO2013113882A3 (de) 2013-10-03
CN104093946A (zh) 2014-10-08
RU2595705C2 (ru) 2016-08-27
JP2015507125A (ja) 2015-03-05
RU2014135644A (ru) 2016-03-27
DE102012002059A1 (de) 2013-08-08

Similar Documents

Publication Publication Date Title
US9599003B2 (en) Method for operating a metering device, metering device and motor vehicle
EP0953739B1 (de) Verfahren und Vorrichtung zur Abgasnachbehandlung für eine mit einem SCR-Katalsator ausgestattete Brennkraftmaschine
US9546584B2 (en) Multi-stage SCR system
US9404408B2 (en) Device and method for metering a reducing agent into an exhaust gas system of a motor vehicle
EP2187009B1 (en) Method for operating an exhaust gas treatment system
US8132405B2 (en) Exhaust emission purifying apparatus for engine
CN102042065B (zh) 监控排气后处理系统中的还原剂喷射系统的方法和装置
US8820053B2 (en) Method for operating a delivery device for a reducing agent and motor vehicle having a delivery device
CN101542081B (zh) 用于运行试剂计量阀的方法以及用于实施所述方法的装置
US9140165B2 (en) Method for operating a delivery unit for a reducing agent and motor vehicle having a delivery unit
US20140338311A1 (en) Method for operating a dosing apparatus and motor vehicle having a dosing apparatus
US8091343B2 (en) Exhaust gas purification apparatus for internal combustion engine
CN105658921B (zh) 用于柴油机排气系统中的低温定量供给的系统、方法和装置
CN103850761A (zh) 选择性催化还原系统及其吹扫方法
CN108691627B (zh) 用于确定流体的配给系统中的量偏差的方法
KR20130117869A (ko) 배기 가스 후처리 시스템을 관리 및 조정하기 위한 방법
CN102374003A (zh) 用于监控计量装置的方法
EP3126645A1 (en) Anti-clogging device for diesel exhaust fluid supply
KR102361893B1 (ko) 시약 계량 시스템을 진단하는 방법, 상기 방법을 수행하기 위한 장치, 컴퓨터 프로그램 및 컴퓨터 프로그램 제품
CN208718763U (zh) 一种空气辅助式尿素溶液供给系统
CN115341979A (zh) 用于控制尿素水溶液的喷射的方法、控制装置和可读存储介质
WO2020049131A1 (en) A pump module for a dosing system and a non-return valve assembly therefor
CN102597445B (zh) 用于调整喷射气相还原剂的量的装置及其方法
CN101922332B (zh) 一种保持柴油机scr系统喷射压力恒定的装置及方法
RU2587800C2 (ru) Подающее устройство для подачи жидкой добавки из бака и способ для этого

Legal Events

Date Code Title Description
AS Assignment

Owner name: EMITEC GESELLSCHAFT FUER EMISSIONSTECHNOLOGIE MBH,

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BRUECK, ROLF;HODGSON, JAN;REEL/FRAME:033691/0197

Effective date: 20140828

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION