EP0262390A1 - Procédé pour opérer des brûleurs à prémélange et dispositif d'exécution de ce procédé - Google Patents

Procédé pour opérer des brûleurs à prémélange et dispositif d'exécution de ce procédé Download PDF

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Publication number
EP0262390A1
EP0262390A1 EP87112359A EP87112359A EP0262390A1 EP 0262390 A1 EP0262390 A1 EP 0262390A1 EP 87112359 A EP87112359 A EP 87112359A EP 87112359 A EP87112359 A EP 87112359A EP 0262390 A1 EP0262390 A1 EP 0262390A1
Authority
EP
European Patent Office
Prior art keywords
flame
combustion
ionization current
burner
measured
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.)
Granted
Application number
EP87112359A
Other languages
German (de)
English (en)
Other versions
EP0262390B1 (fr
Inventor
Detlef Dr. Ing. Altemark
Robert Dr. Ing. Hess
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.)
EON Ruhrgas AG
Original Assignee
Ruhrgas AG
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 Ruhrgas AG filed Critical Ruhrgas AG
Priority to AT87112359T priority Critical patent/ATE73218T1/de
Publication of EP0262390A1 publication Critical patent/EP0262390A1/fr
Application granted granted Critical
Publication of EP0262390B1 publication Critical patent/EP0262390B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N5/00—Systems for controlling combustion
    • F23N5/02—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium
    • F23N5/12—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using ionisation-sensitive elements, i.e. flame rods
    • F23N5/123—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using ionisation-sensitive elements, i.e. flame rods using electronic means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N2225/00—Measuring
    • F23N2225/26—Measuring humidity
    • F23N2225/30—Measuring humidity measuring lambda

Definitions

  • the invention relates to a method for operating premix burners under normal or elevated pressure in which a gaseous or vaporous fuel and combustion air are preferably mixed with cooling gas in a mixing chamber and subsequently reacted in a combustion chamber to form a flame, and in which the combustion is carried out with a low flame temperature and thus flame speed due to specified boundary conditions.
  • NO x nitrogen oxides
  • the combustion of gaseous or liquid fuels is known to produce nitrogen oxides (NO x ) in the exhaust gas, which are undesirable both from the point of view of air pollution and from the point of view of the treatment goods coming into contact with burner exhaust gases.
  • NO x mainly forms on the one hand from the nitrogen bound in the fuel and on the other hand thermally from free nitrogen, which is contained in the air and possibly also in certain fuels, for example in natural gas.
  • Thermal NO x formation occurs primarily at high combustion temperatures, for example in natural gas from approx. 1600 ° C.
  • the object of the invention is to operate the premix burner as close as possible to the flame stability limit in order to minimize the NO x emission when the burnout is complete, and to reliably prevent the flame stability limit from being exceeded.
  • the invention is based on the knowledge that if the boundary conditions for a homogeneous flame development on the burner, as known from the above-mentioned document, are observed, the property values of the flame itself give the best and fastest conclusions about the combustion, in particular the desired low-emission combustion allow and are therefore particularly suitable as control variables.
  • the invention therefore provides that at least one variable (flame property) characteristic of the distance of the flame from the flame stability limit is monitored or measured on or in the burner flame and as a control variable for controlling the flow rate of at least one of the mixture components supplied to the mixing chamber is used in such a way that the combustion takes place as close as possible to the flame stability limit.
  • the selection of the medium, i.e. fuel, combustion air or cooling gas, the flow of which is influenced by the control depends on the application area of the burner.
  • the desired approach of combustion to the flame stability limit is best and quickest to monitor via a flame property, so that the use of the flame property as a control variable for the action on the ratio of the mixture media ensures a responsive control.
  • the following flame properties come into consideration as parameters which are characteristic of the distance of the flame from the flame stability limit and which are monitored and used as a control variable: the ionization current, pressure pulsations, temperatures and UV radiation of the flame.
  • the ionization current of the flame has proven to be the most advantageous control variable, since it follows changes in the flame without a time delay, can be detected quickly and can be easily measured both locally in the form of a point measurement and integrally over a certain range.
  • the ionization current can either be tapped at the flame monitoring device or, if the burner has ionization monitoring, or by means of at least one separate pair of electrodes, the ground electrode (cathode) being part of the burner.
  • the ionization current can also be detected using a large number of specially arranged electrodes or pairs of electrodes.
  • the signal for determining the flame stability limit can be improved by means of the modulation, that is to say a systematic change in the fuel / combustion air and possibly the cooling gas mixture ratio at the flame stability limit.
  • a ⁇ control may be provided as a follow-up control.
  • FIG. 1 shows the mean value of the ionization current I measured as a function of the air ratio ⁇ in the flame of a burner which is premixed more than stoichiometrically.
  • the characteristic fluctuations in the ionization current are suppressed by appropriate damping.
  • the mean of the ionization current initially decreases only slightly at an air ratio ⁇ > 1, but then increases increasingly sharply and reaches the value 0 when the air ratio ⁇ reaches the flame stability limit.
  • the average value of the ionization current changes very strongly near the flame stability limit with comparatively small changes in the air ratio ⁇ and is therefore particularly suitable as a control variable for a burner to be operated as close as possible to the flame stability limit.
  • the setpoint shown in FIG. 1 is only shown as an example.
  • the amplitude of the ionization current fluctuations of the flame (FIG. 2) can also be monitored.
  • the ionization current fluctuates increasingly around the decreasing mean value.
  • the amplitude of the ionization current fluctuations is therefore also suitable as a control variable for a burner operated close to the flame stability limit.
  • the measurement signal, the ionization current I is processed undamped.
  • the frequency spectrum of the ionization current fluctuations in the flame changes the closer one is to the flame stability limit.
  • the frequency spectrum of the ionization current fluctuations in the flame is therefore also suitable as a control variable.
  • a device according to the invention for performing the method is shown schematically in FIG. 3:
  • a premix burner 1 known from EP-B-0 021 035 has a mixing tube 2 in which fuel 3, combustion air 4 and cooling gas 5 are mixed to form a homogeneous gas mixture.
  • a conically enlarged burner head 6 Connected to the mixing tube 2 is a conically enlarged burner head 6 with a burner plate 7, which has a large main flame bore 8 and small bores 9 arranged in concentric circles around the bore 8.
  • a pre-combustion chamber with the burner mouth 10 connects to the burner plate 7 and is connected to a flame protection sleeve 12 shielding the flame 11.
  • An electrode 13 is arranged in the flame 11, e.g. together with an electrode 14 arranged on the burner wall forms a pair of electrodes for measuring the ionization current of the flame 1.
  • the electrodes 13 and 14 are connected to a transmitter 15, the output signal of which is fed to a controller 16 as a controlled variable.
  • the controller 16 converts the controlled variable via the actuators 17, 18, 19 into suitable changes in the mass flows of the mixture components 3, 4, 5 in such a way that combustion takes place as close as possible to the stability limit of the flame 11.
  • the invention therefore ensures a quiet, reliable and low-pollutant combustion over a wide power range, with the flame being reliably maintained close to the stability limit.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
EP87112359A 1986-09-04 1987-08-26 Procédé pour opérer des brûleurs à prémélange et dispositif d'exécution de ce procédé Expired - Lifetime EP0262390B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT87112359T ATE73218T1 (de) 1986-09-04 1987-08-26 Verfahren zum betreiben von vormischbrennern und vorrichtung zum durchfuehren dieses verfahrens.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19863630177 DE3630177A1 (de) 1986-09-04 1986-09-04 Verfahren zum betreiben von vormischbrennern und vorrichtung zum durchfuehren dieses verfahrens
DE3630177 1986-09-04

Publications (2)

Publication Number Publication Date
EP0262390A1 true EP0262390A1 (fr) 1988-04-06
EP0262390B1 EP0262390B1 (fr) 1992-03-04

Family

ID=6308943

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87112359A Expired - Lifetime EP0262390B1 (fr) 1986-09-04 1987-08-26 Procédé pour opérer des brûleurs à prémélange et dispositif d'exécution de ce procédé

Country Status (4)

Country Link
US (1) US4859171A (fr)
EP (1) EP0262390B1 (fr)
AT (1) ATE73218T1 (fr)
DE (2) DE3630177A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2226163A (en) * 1988-11-10 1990-06-20 Vaillant Joh Gmbh & Co Air/fuel ratio control for a burner
EP0643265A1 (fr) * 1993-09-13 1995-03-15 Ruhrgas Aktiengesellschaft Procédé et dispositif de commande de brûleurs à gaz avec prémélange et excès d'air
US7513117B2 (en) 2004-07-29 2009-04-07 Alstom Technology Ltd Method for operating a furnace
CN107402274A (zh) * 2016-05-20 2017-11-28 保时捷股份公司 过滤器泄出测量组件和储箱泄出测量组件

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5073104A (en) * 1985-09-02 1991-12-17 The Broken Hill Proprietary Company Limited Flame detection
ES2017123A6 (es) * 1989-05-26 1991-01-01 Gabas Cebollero Carlos Puente de sujecion acoplable a viseras parasol de vehiculos automoviles.
EP0861402A1 (fr) * 1995-11-13 1998-09-02 Gas Research Institute Appareil et procede de commande d'ionisation de flamme
DE19631821C2 (de) * 1996-08-07 1999-08-12 Stiebel Eltron Gmbh & Co Kg Verfahren und Einrichtung zur Sicherheits-Flammenüberwachung bei einem Gasbrenner
ES2158400T3 (es) * 1996-05-09 2001-09-01 Stiebel Eltron Gmbh & Co Kg Procedimiento para el funcionamiento de un quemador de gas.
US6299433B1 (en) 1999-11-05 2001-10-09 Gas Research Institute Burner control
US7096722B2 (en) * 2002-12-26 2006-08-29 Woodward Governor Company Method and apparatus for detecting combustion instability in continuous combustion systems
US7908847B2 (en) * 2004-01-13 2011-03-22 Emcon Technologies Llc Method and apparatus for starting up a fuel-fired burner of an emission abatement assembly
US7241135B2 (en) 2004-11-18 2007-07-10 Honeywell International Inc. Feedback control for modulating gas burner
US8046988B2 (en) * 2006-02-28 2011-11-01 Caterpillar Inc. System having multiple valves operated by common controller
US8821154B2 (en) * 2010-11-09 2014-09-02 Purpose Company Limited Combustion apparatus and method for combustion control thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3155145A (en) * 1959-10-05 1964-11-03 Hupp Corp Control circuit for gas burner
EP0021035A1 (fr) * 1979-06-29 1981-01-07 Ruhrgas Aktiengesellschaft Procédé de fonctionnement de brûleurs à prémélange et brûleur pour la mise en oeuvre de ce procédé
EP0071067A1 (fr) * 1981-07-24 1983-02-09 Kabushiki Kaisha Toshiba Dispositif de commande pour une combustion
EP0146690A1 (fr) * 1983-08-22 1985-07-03 Honeywell Inc. Détecteur de flamme
NL8403840A (nl) * 1984-12-18 1986-07-16 Tno Inrichting voor het regelen van de gasbrandstof-luchtverhouding in een brander van een gasgestookte ketel.

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US2324821A (en) * 1939-02-08 1943-07-20 Gen Electric Measuring and control method and apparatus
US2352143A (en) * 1940-04-27 1944-06-20 Brown Instr Co Control apparatus
US3768955A (en) * 1972-06-26 1973-10-30 Universal Oil Prod Co Reactant ratio control process
DE2448430A1 (de) * 1973-10-30 1975-05-07 Satronic Ag Verfahren zur zuendfunken- und flammenueberwachung an brennern
GB1461653A (en) * 1974-05-23 1977-01-19 Land Pyrometers Ltd Burner control
GB1495015A (en) * 1975-09-01 1977-12-14 British Petroleum Co Monitoring and/or control of burners
US4043742A (en) * 1976-05-17 1977-08-23 Environmental Data Corporation Automatic burner monitor and control for furnaces
DE2950689A1 (de) * 1979-12-17 1981-06-25 Servo-Instrument, in Deutschland Alleinvertrieb der BEAB-Regulatoren GmbH u. Co KG, 4050 Mönchengladbach Regelvorrichtung fuer die verbrennungsluftmenge einer feuerstaette
US4477245A (en) * 1982-09-03 1984-10-16 The Babcock & Wilcox Company Flame monitoring safety, energy and fuel conservation system
US4588372A (en) * 1982-09-23 1986-05-13 Honeywell Inc. Flame ionization control of a partially premixed gas burner with regulated secondary air
US4645450A (en) * 1984-08-29 1987-02-24 Control Techtronics, Inc. System and process for controlling the flow of air and fuel to a burner

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3155145A (en) * 1959-10-05 1964-11-03 Hupp Corp Control circuit for gas burner
EP0021035A1 (fr) * 1979-06-29 1981-01-07 Ruhrgas Aktiengesellschaft Procédé de fonctionnement de brûleurs à prémélange et brûleur pour la mise en oeuvre de ce procédé
EP0071067A1 (fr) * 1981-07-24 1983-02-09 Kabushiki Kaisha Toshiba Dispositif de commande pour une combustion
EP0146690A1 (fr) * 1983-08-22 1985-07-03 Honeywell Inc. Détecteur de flamme
NL8403840A (nl) * 1984-12-18 1986-07-16 Tno Inrichting voor het regelen van de gasbrandstof-luchtverhouding in een brander van een gasgestookte ketel.

Non-Patent Citations (8)

* Cited by examiner, † Cited by third party
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PATENT ABSTRACTS OF JAPAN, Band 3, Nr. 53 (M-58), 8. Mai 1979; & JP-A-54 30 537 (HITACHI NETSUKIGU K.K.) 03.07.1979 *
PATENT ABSTRACTS OF JAPAN, Band 7, Nr. 112 (M-215)[1257], 17. May 1983; & JP-A-58 33 025 (MATSUSHITA DENKI SANGYO K.K.) 26.02.1983 *
PATENT ABSTRACTS OF JAPAN, Band 7, Nr. 199 (M-240)[1344], 3. September 1983; & JP-A-58 99 613 (MITSUBISHI JUKOGYO K.K.) 14.06.1983 *
PATENT ABSTRACTS OF JAPAN, Band 9, Nr. 135 (M-386)[1858], 11. Juni 1985; & JP-A-60 16 218 (RINNAI K.K.) 28.01.1985 *
PATENT ABSTRACTS OF JAPAN, Band 9, Nr. 172 (M-397)[1895], 17. July 1985; & JP-A-60 44 724 (MATSUSHITA DENKI SANGYO K.K.) 09.03.1985 *
PATENT ABSTRACTS OF JAPAN, Band 9, Nr. 187 (M-401)[1910], 3. August 1985; & JP-A-60 53 716 (ISEKI NOKI K.K.) 27.03.1985 *
PATENT ABSTRACTS OF JAPAN, Band 9, Nr. 209 (M-407)[1932], 27. August 1985; & JP-A-60 69 428 (BABCOCK HITACHI K.K.) 20.04.1985 *
PATENT ABSTRACTS OF JAPAN, Band 9, Nr. 55 (M-362)[1778], 09. März 1985; & JP-A-59 189 216 (MATSUSHITA DENKI SANGYO K.K.) 26.10.1984 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2226163A (en) * 1988-11-10 1990-06-20 Vaillant Joh Gmbh & Co Air/fuel ratio control for a burner
EP0643265A1 (fr) * 1993-09-13 1995-03-15 Ruhrgas Aktiengesellschaft Procédé et dispositif de commande de brûleurs à gaz avec prémélange et excès d'air
US7513117B2 (en) 2004-07-29 2009-04-07 Alstom Technology Ltd Method for operating a furnace
CN107402274A (zh) * 2016-05-20 2017-11-28 保时捷股份公司 过滤器泄出测量组件和储箱泄出测量组件

Also Published As

Publication number Publication date
US4859171A (en) 1989-08-22
ATE73218T1 (de) 1992-03-15
DE3777053D1 (de) 1992-04-09
DE3630177A1 (de) 1988-03-10
EP0262390B1 (fr) 1992-03-04

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