EP0394800A1 - Brûleur à mélange préalable pour la génération de gaz chaud - Google Patents

Brûleur à mélange préalable pour la génération de gaz chaud Download PDF

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Publication number
EP0394800A1
EP0394800A1 EP90107192A EP90107192A EP0394800A1 EP 0394800 A1 EP0394800 A1 EP 0394800A1 EP 90107192 A EP90107192 A EP 90107192A EP 90107192 A EP90107192 A EP 90107192A EP 0394800 A1 EP0394800 A1 EP 0394800A1
Authority
EP
European Patent Office
Prior art keywords
fuel
burner
premix burner
combustion air
flow
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
EP90107192A
Other languages
German (de)
English (en)
Other versions
EP0394800B1 (fr
Inventor
Jakob Dr. Keller
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 Asea Brown Boveri Ltd
ABB AB
Original Assignee
ABB Asea Brown Boveri Ltd
Asea Brown Boveri AB
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 Asea Brown Boveri Ltd, Asea Brown Boveri AB filed Critical ABB Asea Brown Boveri Ltd
Publication of EP0394800A1 publication Critical patent/EP0394800A1/fr
Application granted granted Critical
Publication of EP0394800B1 publication Critical patent/EP0394800B1/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
    • F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R3/00—Continuous combustion chambers using liquid or gaseous fuel
    • F23R3/02—Continuous combustion chambers using liquid or gaseous fuel characterised by the air-flow or gas-flow configuration
    • F23R3/04—Air inlet arrangements
    • F23R3/10—Air inlet arrangements for primary air
    • F23R3/12—Air inlet arrangements for primary air inducing a vortex
    • 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
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C9/00—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber
    • F23C9/08—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber for reducing temperature in combustion chamber, e.g. for protecting walls of combustion chamber
    • 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 
    • F23C2202/00—Fluegas recirculation
    • F23C2202/30—Premixing fluegas with combustion air
    • 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

Definitions

  • the present invention relates to a premix burner for hot gas production according to the preamble of claim 1. It also relates to a method for operating such a premix burner.
  • a burner is known from EP-A1-0 210 462, which is formed from at least two double-curved hollow partial cone bodies, each of which has a tangential air inlet. These bodies unfold in the flow direction along diagonals that open in a cone-shaped manner.
  • One curved body forms an inner cone with an increasing cone opening in the outflow direction, while the other curved body forms an outer cone with a decreasing cone opening in the outflow direction.
  • the inner cones along their entire axial extent, each carry a fuel line for supplying the gaseous fuel, which flows through several fuel nozzles into the interior of the burner, in order to mix there with the combustion air flowing in tangentially.
  • the burner also has a separate supply of a liquid fuel, which is a dual burner.
  • the injection of the liquid fuel is directed axially onto the outer cone in such a way that, depending on the strength of the injection, a different length and consistent fuel film is formed.
  • a weighty fuel mixture is created by the tangentially introduced combustion air, which rolls up the fuel film in layers due to its swirling movement in the axial direction, making the generation of a strong swirl superfluous.
  • this burner results in a vortex flow, which on the one hand is low in swirl in the center, but on the other hand has an excess of axial speed. Because the number of swirls increases strongly in the axial direction and reaches the breakdown value at the end of the burner, this results in a positionally stable vortex backflow.
  • the invention is based on the object of expanding a burner of the type mentioned in the introduction in order to further minimize the pollutant emission values in each operation, both when operating with liquid and with gaseous fuels, as well as a mixed operation of the two.
  • a major advantage of the invention is that the use of an exhaust gas recirculation system intervenes simultaneously on the fuel evaporation and on the flame temperature in the combustion chamber. If the burner is operated with liquid fuel, the exhaust gas recirculation, which processes the combustion air calorically, ensures that a completely evaporated fuel / combustion air mixture can be supplied to the combustion. This optimization of the mixture caused by the exhaust gas recirculation then also influences the flame temperature in the combustion chamber in such a way that local peak temperatures, which are responsible for the NO x formation, no longer occur there. If, on the other hand, the burner is operated with gaseous fuel, a gaseous mixture is already present, but the flame temperature also experiences the positive influence described above. With mixed operation with liquid and gaseous fuel, the advantages of exhaust gas recirculation come into play at the same time.
  • a burner operated in this way has improvements in pollutant emissions that are not limited to just a few percentage points, but only the NO x emissions are minimized in such a way that perhaps only 10% of what the legal limit values tolerate is measured. In this way, a completely new level of quality has been achieved.
  • Another advantage of the invention is that exhaust gas recirculation now offers the possibility of optimally operating atmospheric combustion plants with near-stoichiometric operation with regard to pollutant emissions.
  • Another advantage of the invention lies in a preferred embodiment of the burner. Despite the simplest geometrical design, there is no fear of the flame re-igniting from the combustion chamber into the burner. The well-known problems with the use of swirl generators in the mixture stream, such as those caused by burning of deposits with destruction of the swirl blades can therefore not occur here. The improvement in pollutant emissions is also retained.
  • Fig. 1 shows only the basic structure of the burner.
  • the burner body consists of two half-hollow partial cone bodies 1, 2 which, as can be seen more conclusively from FIG. Due to this geometric structure, the term "double-cone burner” is used below.
  • a nozzle 3 ensures the supply of the liquid fuel 12; both partial cone bodies 1, 2 each have a fuel line 8, 9, which are provided with openings 17 through which the gaseous fuel 13 flows in order to then mix with combustion air 15.
  • this combustion air 15 is an air / exhaust gas mixture.
  • This air / exhaust gas mixture arises from a fresh air supply 23a, 23b and from an exhaust gas 22a, 22b which comes from the combustion in the double-cone burner.
  • the advantages of such exhaust gas recirculation are discussed in more detail in FIG. 3. With regard to the circumstances of the schematically illustrated backflow zone 6, reference is made to the description of FIG.
  • the core body of the double-cone burner according to FIG. 2 consists of two half-hollow partial cone bodies 1, 2 which are offset from one another.
  • the offset of the respective central axis 1b, 2b of the partial cone bodies 1, 2 to one another creates a tangential air inlet on both sides in a mirror-image arrangement (see FIG. 3) through which combustion air 15 flows into the interior of the double-cone burner, ie into the cone cavity 14.
  • the two partial cone bodies 1, 2 each have a cylindrical initial part 1a, 2a, which likewise run offset to one another analogously to the partial cone bodies 1, 2, so that the tangential air inlets are present from the beginning.
  • a nozzle 3 is accommodated, the fuel injection 4 with the narrowest cross section of the conical cavity 14 formed by the two partial cone bodies 1, 2 coincides.
  • the size of this nozzle 3 depends on the type of burner. Of course, the double-cone burner can be made purely conical, that is to say without cylindrical starting parts 1a, 2a.
  • Both partial cone bodies 1, 2 each have a fuel line 8, 9, which are provided with fuel nozzles 17 through which the gaseous fuel 13 flows, which is mixed with the combustion air 15 flowing through the tangential air inlets.
  • the double-cone burner has a plate which forms the boiler wall 10.
  • the liquid fuel 12 flowing through the nozzle 3 is injected into the cone cavity 14 at an acute angle such that a cone-shaped fuel spray which is as homogeneous as possible is obtained in the burner outlet plane.
  • the fuel injection 3/4 can also be an air-assisted nozzle or a dual burner with gaseous and liquid fuel supply, as is described, for example, in EP-A1 210 462.
  • the conical liquid fuel profile 5 from the nozzle 3 is now surrounded by the tangentially flowing combustion air 15 in a rotating manner.
  • the concentration of the liquid fuel 12 is continuously reduced by the incoming combustion air 15.
  • gaseous fuel 13 is injected 16
  • the mixture formation with the combustion air 15 takes place directly at the end of the tangential air inlets.
  • the optimal, homogeneous fuel concentration over the cross section is achieved in the region of the vortex run, that is to say in the region of the backflow zone 6, in that the fuel droplets generated by the oil nozzle are forced to have a rotational speed component by the vortex flow.
  • the resulting centrifugal force drives the droplets of the liquid fuel 12 radially outwards.
  • the pollutant emission values are lowest.
  • narrow limits must be observed so that the desired flow field of the air with its backflow zone 6 is established in the area of the burner fatigue for flame stabilization.
  • a reduction in the tangential air inlets displaces the return flow zone 6 further upstream, which would then cause the mixture to ignite earlier.
  • the backflow zone 6, which is once geometrically fixed, is inherently position-stable, because the swirl number increases in the direction of flow in the region of the cone shape of the burner.
  • this double-cone burner is ideally suited to change the size of the tangential air inlets for a given overall length of the burner, in that the part-cone bodies 1, 2 are fixed to the boiler wall 10 by means of a releasable connection.
  • the distance between the two central axes 1b, 2b decreases or increases as a result of radial displacement of the two partial cone bodies 1, 2 to and from one another, and the gap size of the tangential air inlets changes accordingly, as can be seen particularly well from FIG is enforceable.
  • Fig. 2 shows only a hint the one inlet 20a, which guides the combustion air 15 tangentially into the cavity 14.
  • the other non-visible inlet 20b and the overall configuration of the same are shown in FIG.
  • the inlets 20a, 20b which are arranged in mirror image tangentially, are designed as diffusers, to reinforce the effect of the jet provided at the beginning of the diffuser.
  • Injector 21a, 21b The air supply duct 23a, 23b, as a continuation of the inlets 20a, 20b, contains an exhaust gas recirculation funnel 22a, 22b, the output of which coincides with the plane of action of the jet injector 21a, 21b. It can be seen from this that the combustion air 15 is an air / exhaust gas mixture, as was briefly mentioned in FIG. 1.
  • This recirculation of a quantity of a partially cooled exhaust gas with a temperature of approx. 950 ° C. is necessary for optimal operation of the double-cone burner when it is used in atmospheric combustion plants with a near-stoichiometric mode of operation.
  • the optimal mass flow ratio ie the ratio between recirculated exhaust gas and fresh air supplied, is approximately 0.7.
  • a fresh air temperature of, for example, 15 ° C.
  • an exhaust gas temperature of approximately 950 ° C. a mixed temperature of the air / exhaust gas mixture 15 of approximately 400 ° C. is reached.
  • a double-cone burner with a thermal output of around 100-200 kW these conditions lead to optimal evaporation conditions for the liquid fuel and to a minimization of NO x / CO / UHC emissions.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Gas Burners (AREA)
  • Pre-Mixing And Non-Premixing Gas Burner (AREA)
EP90107192A 1989-04-24 1990-04-14 Brûleur à mélange préalable pour la génération de gaz chaud Expired - Lifetime EP0394800B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH1546/89A CH679692A5 (fr) 1989-04-24 1989-04-24
CH1546/89 1989-04-24

Publications (2)

Publication Number Publication Date
EP0394800A1 true EP0394800A1 (fr) 1990-10-31
EP0394800B1 EP0394800B1 (fr) 1993-11-18

Family

ID=4212944

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90107192A Expired - Lifetime EP0394800B1 (fr) 1989-04-24 1990-04-14 Brûleur à mélange préalable pour la génération de gaz chaud

Country Status (5)

Country Link
US (1) US5127821A (fr)
EP (1) EP0394800B1 (fr)
JP (1) JP2933673B2 (fr)
CH (1) CH679692A5 (fr)
DE (1) DE59003501D1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993014348A1 (fr) * 1992-01-10 1993-07-22 Wiser Oy CALCINATION AVEC ELIMINATION DU NOx GAZEUX
EP0629817A2 (fr) * 1993-06-18 1994-12-21 Abb Research Ltd. Foyer
US5482457A (en) * 1992-10-16 1996-01-09 Asea Brown Boveri Ltd. Gas-operated premixing burner
EP1262714A1 (fr) * 2001-06-01 2002-12-04 ALSTOM (Switzerland) Ltd Brûleur avec recirculation des gaz de combustion
DE102006003150B4 (de) * 2006-01-23 2009-04-16 Webasto Ag Zusatzheizgerät mit einem Brenner der Einspritzbauart

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993009384A1 (fr) * 1991-10-28 1993-05-13 Irvin Glassman Combustion a tourbillons asymmetriques
US5735681A (en) * 1993-03-19 1998-04-07 The Regents, University Of California Ultralean low swirl burner
DE4316474A1 (de) * 1993-05-17 1994-11-24 Abb Management Ag Vormischbrenner zum Betrieb einer Brennkraftmaschine, einer Brennkammer einer Gasturbogruppe oder Feuerungsanlage
DE4330083A1 (de) * 1993-09-06 1995-03-09 Abb Research Ltd Verfahren zum Betrieb eines Vormischbrenners
DE4411622A1 (de) * 1994-04-02 1995-10-05 Abb Management Ag Vormischbrenner
DE4422535A1 (de) * 1994-06-28 1996-01-04 Abb Research Ltd Verfahren zum Betrieb einer Feuerungsanlage
DE4441641A1 (de) * 1994-11-23 1996-05-30 Abb Management Ag Brennkammer mit Vormischbrennern
DE19548853A1 (de) * 1995-12-27 1997-07-03 Abb Research Ltd Kegelbrenner
EP0918191B1 (fr) * 1997-11-21 2003-07-02 Alstom Brûleur pour la mise en oeuvre d'un générateur de chaleur
AU2001272682A1 (en) * 2000-06-15 2001-12-24 Alstom Power N.V. Method for operating a burner and burner with stepped premix gas injection
DE10040869A1 (de) * 2000-08-21 2002-03-07 Alstom Power Nv Verfahren und Vorrichtung zur Unterdrückung von Strömungswirbeln innerhalb einer Strömungskraftmaschine
EP1510755B1 (fr) * 2003-09-01 2016-09-28 General Electric Technology GmbH Brûleur avec lance et alimentation étagée en carburant

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2043869A (en) * 1979-02-28 1980-10-08 United Stirling Ab & Co Device for combustion of a fuel with air
EP0210462A1 (fr) * 1985-07-30 1987-02-04 BBC Brown Boveri AG Chambre de combustion double
EP0321809B1 (fr) * 1987-12-21 1991-05-15 BBC Brown Boveri AG Procédé pour la combustion de combustible liquide dans un brûleur

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE413283C (de) * 1925-05-05 Faconeisen Walzwerk L Mannstae Gasfeuerung fuer Dampfkessel und Drehtrommeln
GB315466A (en) * 1928-04-14 1929-07-15 Babcock Und Wilcox Dampfkessel Improvements in fuel burners
US2881719A (en) * 1949-07-08 1959-04-14 Babcock & Wilcox Co Cyclone furnace
GB817936A (en) * 1956-08-03 1959-08-06 Power Jets Res & Dev Ltd Vortex flow reaction chambers
US3868211A (en) * 1974-01-11 1975-02-25 Aqua Chem Inc Pollutant reduction with selective gas stack recirculation
US4023921A (en) * 1975-11-24 1977-05-17 Electric Power Research Institute Oil burner for NOx emission control
DE3706234A1 (de) * 1987-02-26 1988-09-08 Sonvico Ag Ing Bureau Brenner zum verbrennen von fluessigen oder gasfoermigen brennstoffen

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2043869A (en) * 1979-02-28 1980-10-08 United Stirling Ab & Co Device for combustion of a fuel with air
EP0210462A1 (fr) * 1985-07-30 1987-02-04 BBC Brown Boveri AG Chambre de combustion double
EP0321809B1 (fr) * 1987-12-21 1991-05-15 BBC Brown Boveri AG Procédé pour la combustion de combustible liquide dans un brûleur

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993014348A1 (fr) * 1992-01-10 1993-07-22 Wiser Oy CALCINATION AVEC ELIMINATION DU NOx GAZEUX
US5482457A (en) * 1992-10-16 1996-01-09 Asea Brown Boveri Ltd. Gas-operated premixing burner
EP0629817A2 (fr) * 1993-06-18 1994-12-21 Abb Research Ltd. Foyer
DE4320212A1 (de) * 1993-06-18 1994-12-22 Abb Research Ltd Feuerungsanlage
EP0629817A3 (fr) * 1993-06-18 1995-05-31 Abb Research Ltd Foyer.
US5423674A (en) * 1993-06-18 1995-06-13 Abb Research Ltd. Firing installation
EP1262714A1 (fr) * 2001-06-01 2002-12-04 ALSTOM (Switzerland) Ltd Brûleur avec recirculation des gaz de combustion
US6672863B2 (en) 2001-06-01 2004-01-06 Alstom Technology Ltd Burner with exhaust gas recirculation
DE102006003150B4 (de) * 2006-01-23 2009-04-16 Webasto Ag Zusatzheizgerät mit einem Brenner der Einspritzbauart

Also Published As

Publication number Publication date
JP2933673B2 (ja) 1999-08-16
EP0394800B1 (fr) 1993-11-18
JPH02293512A (ja) 1990-12-04
CH679692A5 (fr) 1992-03-31
US5127821A (en) 1992-07-07
DE59003501D1 (de) 1993-12-23

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