EP0641971A2 - Procédé pour commander un brûleur à prémélange - Google Patents

Procédé pour commander un brûleur à prémélange Download PDF

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Publication number
EP0641971A2
EP0641971A2 EP94112811A EP94112811A EP0641971A2 EP 0641971 A2 EP0641971 A2 EP 0641971A2 EP 94112811 A EP94112811 A EP 94112811A EP 94112811 A EP94112811 A EP 94112811A EP 0641971 A2 EP0641971 A2 EP 0641971A2
Authority
EP
European Patent Office
Prior art keywords
premix burner
fuel
section
partial bodies
inlet slots
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
EP94112811A
Other languages
German (de)
English (en)
Other versions
EP0641971B1 (fr
EP0641971A3 (fr
Inventor
Klaus Dr. Döbbeling
Hans Peter Knöpfel
Thomas Dr. Sattelmayer
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.)
ABB Research Ltd Switzerland
ABB Research Ltd Sweden
Original Assignee
ABB Research Ltd Switzerland
ABB Research Ltd Sweden
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 ABB Research Ltd Switzerland, ABB Research Ltd Sweden filed Critical ABB Research Ltd Switzerland
Publication of EP0641971A2 publication Critical patent/EP0641971A2/fr
Publication of EP0641971A3 publication Critical patent/EP0641971A3/fr
Application granted granted Critical
Publication of EP0641971B1 publication Critical patent/EP0641971B1/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
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C7/00—Combustion apparatus characterised by arrangements for air supply
    • F23C7/002—Combustion apparatus characterised by arrangements for air supply the air being submitted to a rotary or spinning motion
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D11/00—Burners using a direct spraying action of liquid droplets or vaporised liquid into the combustion space
    • F23D11/36—Details, e.g. burner cooling means, noise reduction means
    • F23D11/40—Mixing tubes or chambers; Burner heads
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/46—Details, e.g. noise reduction means
    • F23D14/62—Mixing devices; Mixing tubes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D17/00—Burners for combustion conjointly or alternatively of gaseous or liquid or pulverulent fuel
    • F23D17/002—Burners for combustion conjointly or alternatively of gaseous or liquid or pulverulent fuel gaseous or liquid fuel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C2900/00—Special features of, or arrangements for combustion apparatus using fluid fuels or solid fuels suspended in air; Combustion processes therefor
    • F23C2900/07002—Premix burners with air inlet slots obtained between offset curved wall surfaces, e.g. double cone burners
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D2214/00—Cooling

Definitions

  • the present invention relates to a method according to the preamble of claim 1. It also relates to a burner for carrying out the method.
  • the mixture formation from fresh air, possibly enriched by a quantity of recirculated exhaust gas, and fuel to form a combustion air flow takes place in such a way that the premix burner can have different fuel injections.
  • a first possibility is that at the beginning of the premix burner, that is to say in the area of its smallest cross-section, at least one fuel nozzle is provided, which is placed in the center of the mutually offset central axes of the partial bodies.
  • a further fuel injection which can either be operated individually or is operatively connected to the aforementioned fuel nozzle, is provided by providing a series of fuel nozzles along the tangential inlet slots at the transition to the interior.
  • the injection of a liquid fuel through the nozzle placed in the middle occurs in such a way that a conical spray-like fuel column forms in the direction of flow of the premix burner, which, however, does not wet the inner walls of the cone cavity.
  • This fuel column is enclosed by the air flow flowing into the interior and, if need be, by an axially brought in further air flow, in such a way that a mixture formation takes place within the premix burner.
  • This mixture comes to ignition at the outlet of the premix burner, with stabilization of the flame front being induced in the region of this burner mouth by a backflow zone formed there.
  • the invention seeks to remedy this.
  • the invention is based on the object of proposing means in a method and in a burner for carrying out the method of the type mentioned at the outset which ensure stable premix combustion with the lowest possible degree of turbulence and minimized NOx emissions.
  • the remedy in the present invention is introduced at a suitable point of a venturi mixer which is connected upstream of the interior of the burner in the combustion air flow.
  • the venturi mixer can be expanded with a cooling air flow.
  • the type of design offers great advantages especially when the fuel has high hydrogen contents.
  • the fuel is injected to a point where the highest combustion air speed prevails.
  • the lower flame speeds at the exit of the burner can induce better flame stability, i.e. trigger lower pulsations.
  • the Venturi mixer enables a good mixture formation between fuel and air with a low pressure drop.
  • the invention also has a further significant advantage, which consists in the fact that no premixing section for a fuel injected there has to be provided above the tangential inlet slots, so that the original compactness of the burner is not lost due to the expansion to fuels with a high hydrogen content.
  • the invention also makes it unnecessary to increase the fuel pressure before the fuel is injected, in order to provide better mixture formation, as is always the case with conventional premixing sections.
  • FIG. 1 In order to better understand the structure of the premix burner X, it is advantageous if, at the same time as in FIG. 1, FIG. 2, and possibly also FIG. 3, which show a radial section through the premix burner X are used. Furthermore, in order not to make FIG. 1 unnecessarily confusing, the venturi mixers shown in FIGS. 2 and 3 in the region or above the tangential air inlet slots and the combustion air supply have not been shown. In the following, reference is also made to the other figures in the description of FIG. 1, if necessary for clarification.
  • the premix burner X according to FIG. 1 consists of two half-conical partial bodies 1, 2 which are offset from one another.
  • the number of tapered partial bodies required to form the premix burner X is not limited to two.
  • the conical shape of the partial bodies 1, 2 shown has a certain fixed angle in the direction of flow.
  • the partial bodies 1, 2 can have a different opening configuration in the flow direction, for example a regular or irregular increasing cone inclination, which leads to a trumpet shape, or a regular or irregular decreasing cone inclination, which leads to a tulip shape.
  • the last two forms are not included in the drawing, since they are easy to understand. Which form is ultimately chosen depends on the various parameters of the respective combustion.
  • the offset of the respective central axis 1b, 2b of the conical partial bodies 1, 2 to one another creates on both sides in Axially symmetrical arrangement each free a tangential air inlet slot 21, 22 (Fig. 2 + 3) and an axial inflow cross section 18 through which the combustion air 15, 16 consisting of a fresh air or a mixture of fresh air and flue gas flows into the interior 14 of the premix burner X.
  • the two tapered partial bodies 1, 2 each have a cylindrical starting part 1a, 2a, which likewise run offset, analogously to the partial bodies 1, 2, so that the tangential air inlet slots 21, 22 are present over the entire length of the premix burner X.
  • the premix burner X can be designed in a purely conical manner, that is to say without cylindrical starting parts 1a, 2a. At least one fuel nozzle 3 is accommodated within this cylindrical starting part 1a, 2a, which is particularly suitable, for example, as a seat for anchoring the entire premix burner X.
  • Both partial bodies 1, 2 each have a fuel line 8, 9, which extends in the axial direction and which are provided with a number of nozzles 17.
  • a gaseous fuel 13 is preferably passed through these lines and is added to the combustion air 15 flowing through the nozzles 17 in the region of the tangential air inlet slots 21, 22 (cf. FIG. 2).
  • the premix burner X can, however, also be operated solely with the fuel supply via the nozzle 3 or via the nozzles 17. Mixed operation is of course possible via both nozzles 3, 17, in particular when different fuels are to be supplied via the individual nozzles.
  • the premix burner X On the combustion chamber side 11, the premix burner X has a collar-shaped plate 10 which has a number of bores 10a through which dilution or cooling air is fed to the front part of the premix burner X. If a liquid fuel is supplied via the nozzle 3, it is injected into the interior 14 of the premix burner X at an acute angle, in such a way that that a conical spray pattern 5 which is as homogeneous as possible is obtained up to the burner outlet level.
  • the fuel injector 4 can be an air-assisted nozzle or a nozzle that works according to a pressure atomization principle.
  • the conical spray pattern 5 is enclosed, corresponding to the number of air inlet slots 21, 22, by combustion air streams 15 flowing in tangentially and by the combustion air 16 which is brought in axially.
  • the concentration of the injected fuel 12 is continuously reduced by the combustion air streams 15, 16 mentioned. If a gaseous fuel 13 is generally introduced in the area of the tangential inlet slots 21, 22, the mixture formation with the combustion air 15 already begins in this area.
  • the optimal, homogeneous fuel concentration over the cross section is achieved in the area of the vortex run, ie in the area of the backflow zone 6 at the end of the premix burner X.
  • the ignition of the fuel / combustion air mixture begins at the top of the return flow zone 6. Only at this point can a stable flame front 7 arise.
  • a flashback of the flame into the interior of the premix burner X as is always to be feared in the case of the premixing sections which have hitherto become known, whereas there is no need to remedy this with complicated flame holders, is not to be feared here.
  • the tapered partial body 1, 2 with respect to the taper and width of the tangential air inlet slots 21, 22, it is advantageous if narrow limits are observed here so that the desired flow field of the combustion air with its return flow zone 6 in the area of the mouth of the premix burner X is Flame stabilization sets.
  • a reduction in the size of the air inlet slots 21, 22 shifts the backflow zone 6 further upstream, but this then causes the mixture to ignite earlier.
  • the once-fixedly fixed backflow zone 6 is inherently position-stable, because the swirl number increases in the direction of flow in the region of the cone shape of the premix burner X.
  • the axial speed of the mixture can also be influenced by the aforementioned axial supply of combustion air 16.
  • the construction of the premix burner X is particularly suitable for the given length of the burner, which should not be exceeded, to change the gap width of the tangentail air inlet slots 21, 22 by the conical partial bodies 1, 2 being able to be moved towards or away from one another, as a result of which the distance between the two Central axes 1b, 2b, as a result, reduced or. enlarged, as can be derived from Fig. 2 well. It is also readily possible to move the tapered partial bodies 1, 2 into one another by means of a rotating movement. It is thus possible, with appropriate precautions, to vary the shape and size of the tangential air inlet slots 21, 22 during operation, which means that the same premix burner X can cover a wide range of functions without changing the overall length.
  • a venturi mixer 32 is provided over the entire length of the premix burner, which consists of a double passage, ie consists of flows 33, 34.
  • the middle venturi body 35 also serves as a fuel feed line. It is further provided with nozzles 36 on both sides in the direction of the above-mentioned flows 33, 34.
  • the flows 33, 34 develop a venturi effect in that the two other adjacent bodies 37, 38 are also designed in a venturi manner.
  • This simple splitting of the venturi mixer 32 has the effect that the overall length of the mixture-forming area can be minimized sustainably without having to forego the advantages of individual venturi sections.
  • This splitting can be a multiple, and can also be carried out in the sense of a Venturi matrix, not shown. In the latter possible embodiment, it is a matter of covering the flow into the interior 14 of the premix burner X with many small pipe venturies.
  • FIG. 3 differs fundamentally from FIG. 2 in that the tapered partial bodies 1, 2 are expanded with additional guide plates 41, 42, through which a cooling air flow 43 also flows, which cools the partial bodies 1, 2 among others.
  • a simple vent flow 45 is created compared to the combustion air 15, which is why the fuel nozzles 46 only act here.
  • Another venturi effect arises in relation to the cooling air flow 43.
  • the venturi body 47 is also designed here as a fuel feed pipe.
  • Venturi mixers 32, 44 are connected upstream of the interior 14 of the premix burner X.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Gas Burners (AREA)
EP94112811A 1993-09-06 1994-08-17 Procédé pour commander un brûleur à prémélange et brûleur pour l'exécution du procédé Expired - Lifetime EP0641971B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4330083A DE4330083A1 (de) 1993-09-06 1993-09-06 Verfahren zum Betrieb eines Vormischbrenners
DE4330083 1993-09-06

Publications (3)

Publication Number Publication Date
EP0641971A2 true EP0641971A2 (fr) 1995-03-08
EP0641971A3 EP0641971A3 (fr) 1995-08-16
EP0641971B1 EP0641971B1 (fr) 1998-05-13

Family

ID=6496954

Family Applications (1)

Application Number Title Priority Date Filing Date
EP94112811A Expired - Lifetime EP0641971B1 (fr) 1993-09-06 1994-08-17 Procédé pour commander un brûleur à prémélange et brûleur pour l'exécution du procédé

Country Status (4)

Country Link
US (1) US5489203A (fr)
EP (1) EP0641971B1 (fr)
JP (1) JPH07208710A (fr)
DE (2) DE4330083A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0718550A1 (fr) * 1994-12-19 1996-06-26 ABB Management AG Gicleur
EP0786626A1 (fr) * 1995-12-27 1997-07-30 Asea Brown Boveri Ag Brûleur à prémélange
EP0807787A2 (fr) * 1996-05-17 1997-11-19 Abb Research Ltd. Brûleur

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4439619A1 (de) * 1994-11-05 1996-05-09 Abb Research Ltd Verfahren und Vorrichtung zum Betrieb eines Vormischbrenners
DE4446842B4 (de) * 1994-12-27 2006-08-10 Alstom Verfahren und Vorrichtung zum Zuleiten eines gasförmigen Brennstoffs in einen Vormischbrenner
DE19654116A1 (de) * 1996-12-23 1998-06-25 Abb Research Ltd Brenner zum Betrieb einer Brennkammer mit einem flüssigen und/oder gasförmigen Brennstoff
US6141954A (en) * 1998-05-18 2000-11-07 United Technologies Corporation Premixing fuel injector with improved flame disgorgement capacity
US6065961A (en) * 1999-02-16 2000-05-23 Shaffer; Yul E. Low NOx burner
DE10050248A1 (de) * 2000-10-11 2002-04-18 Alstom Switzerland Ltd Brenner
DE10051221A1 (de) * 2000-10-16 2002-07-11 Alstom Switzerland Ltd Brenner mit gestufter Brennstoff-Eindüsung
DE50110801D1 (de) * 2000-12-23 2006-10-05 Alstom Technology Ltd Brenner zur Erzeugung eines Heissgases
WO2006058843A1 (fr) * 2004-11-30 2006-06-08 Alstom Technology Ltd Procede et dispositif de combustion d'hydrogene dans un bruleur a premelange
DE502006007811D1 (de) * 2005-06-17 2010-10-21 Alstom Technology Ltd Brenner zur vormischartigen Verbrennung
US20070190382A1 (en) * 2006-02-10 2007-08-16 Fischer Bernhard A Hydrocarbon reformer system
EP1843098A1 (fr) * 2006-04-07 2007-10-10 Siemens Aktiengesellschaft Chambre de combustion pour turbine à gaz
EP2220433B1 (fr) * 2007-11-27 2013-09-04 Alstom Technology Ltd Procédé et dispositif pour la combustion d'hydrogène dans un brûleur à prémélange
WO2009068427A1 (fr) * 2007-11-27 2009-06-04 Alstom Technology Ltd Dispositif et procédé d'utilisation d'une installation de turbine à gaz par recours à un deuxième carburant riche en hydrogène
EP2685163B1 (fr) 2012-07-10 2020-03-25 Ansaldo Energia Switzerland AG Brûleur de prémélange du type multi-cônes destiné à une turbine à gaz
JP6602004B2 (ja) * 2014-09-29 2019-11-06 川崎重工業株式会社 燃料噴射器及びガスタービン
JP2024080498A (ja) * 2022-12-02 2024-06-13 トヨタ自動車株式会社 水素ガスタービンに適した燃焼器及びその燃焼ノズル
KR102532015B1 (ko) * 2022-12-16 2023-05-12 최진민 보일러용 가스 혼합기

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2838103A (en) * 1956-04-03 1958-06-10 Temple S Voorheis Forced air draft burner construction
EP0321809B1 (fr) * 1987-12-21 1991-05-15 BBC Brown Boveri AG Procédé pour la combustion de combustible liquide dans un brûleur
WO1993017279A1 (fr) * 1992-02-26 1993-09-02 United Technologies Corporation Bruleur de gaz a premelange
EP0433790B1 (fr) * 1989-12-22 1995-03-08 Asea Brown Boveri Ag Brûleur

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3217779A (en) * 1963-07-18 1965-11-16 Zink Co John Gas and liquid fuel burner combination
CH679692A5 (fr) * 1989-04-24 1992-03-31 Asea Brown Boveri
CH680946A5 (fr) * 1989-12-19 1992-12-15 Asea Brown Boveri
CH682952A5 (de) * 1991-03-12 1993-12-15 Asea Brown Boveri Brenner für eine Vormischverbrennung eines flüssigen und/oder gasförmigen Brennstoffes.
US5240409A (en) * 1992-04-10 1993-08-31 Institute Of Gas Technology Premixed fuel/air burners

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2838103A (en) * 1956-04-03 1958-06-10 Temple S Voorheis Forced air draft burner construction
EP0321809B1 (fr) * 1987-12-21 1991-05-15 BBC Brown Boveri AG Procédé pour la combustion de combustible liquide dans un brûleur
EP0433790B1 (fr) * 1989-12-22 1995-03-08 Asea Brown Boveri Ag Brûleur
WO1993017279A1 (fr) * 1992-02-26 1993-09-02 United Technologies Corporation Bruleur de gaz a premelange

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0718550A1 (fr) * 1994-12-19 1996-06-26 ABB Management AG Gicleur
EP0786626A1 (fr) * 1995-12-27 1997-07-30 Asea Brown Boveri Ag Brûleur à prémélange
EP0807787A2 (fr) * 1996-05-17 1997-11-19 Abb Research Ltd. Brûleur
EP0807787A3 (fr) * 1996-05-17 1999-03-24 Abb Research Ltd. Brûleur

Also Published As

Publication number Publication date
DE4330083A1 (de) 1995-03-09
EP0641971B1 (fr) 1998-05-13
US5489203A (en) 1996-02-06
EP0641971A3 (fr) 1995-08-16
JPH07208710A (ja) 1995-08-11
DE59405946D1 (de) 1998-06-18

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