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EP0519029B1 - Bruleur a gaz et procede pour son utilisation - Google Patents

Bruleur a gaz et procede pour son utilisation Download PDF

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Publication number
EP0519029B1
EP0519029B1 EP92901135A EP92901135A EP0519029B1 EP 0519029 B1 EP0519029 B1 EP 0519029B1 EP 92901135 A EP92901135 A EP 92901135A EP 92901135 A EP92901135 A EP 92901135A EP 0519029 B1 EP0519029 B1 EP 0519029B1
Authority
EP
European Patent Office
Prior art keywords
housing
injector
gas burner
perforated
burner according
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.)
Expired - Lifetime
Application number
EP92901135A
Other languages
German (de)
English (en)
Other versions
EP0519029A1 (fr
Inventor
Petra Dr.Rer.Nat. Nitschke-Kowsky
Theo Dipl.-Phys. Jannemann
Hans Berg
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.)
Furigas Bv
Original Assignee
Furigas BV
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 Furigas BV filed Critical Furigas BV
Publication of EP0519029A1 publication Critical patent/EP0519029A1/fr
Application granted granted Critical
Publication of EP0519029B1 publication Critical patent/EP0519029B1/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
    • F23D—BURNERS
    • F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/02—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone
    • F23D14/04—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone induction type, e.g. Bunsen burner
    • F23D14/10—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone induction type, e.g. Bunsen burner with elongated tubular burner head
    • F23D14/105—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone induction type, e.g. Bunsen burner with elongated tubular burner head with injector axis parallel to the burner head axis
    • 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
    • F23D14/48—Nozzles
    • F23D14/58—Nozzles characterised by the shape or arrangement of the outlet or outlets from the nozzle, e.g. of annular configuration
    • 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
    • F23D14/72—Safety devices, e.g. operative in case of failure of gas supply
    • F23D14/74—Preventing flame lift-off
    • 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
    • F23D14/72—Safety devices, e.g. operative in case of failure of gas supply
    • F23D14/82—Preventing flashback or blowback
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D2203/00—Gaseous fuel burners
    • F23D2203/10—Flame diffusing means
    • F23D2203/102—Flame diffusing means using perforated plates
    • F23D2203/1023—Flame diffusing means using perforated plates with specific free passage areas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D2211/00—Thermal dilatation prevention or compensation

Definitions

  • the invention relates to a method for operating a atmospheric, substoichiometric premixing gas burner with an injector into which gas is injected, and with a housing supplied by the injector, which mixture passage openings having. Furthermore, the invention is based a burner that can be operated using this method. Such firing is known from DE-A-2 132 968.
  • a premixing gas burner is known from US Pat. No. 3,936,003 an axially associated housing known in a wall Has mixture passage openings, the mixture passage openings have a diameter of 0.5 to 1 mm and are arranged with a degree of perforation of 15 to 30%.
  • this known burner is in particular set up in such a way that in use the gas-air mixture at such a pressure is chased through the mixture openings that So - called "jets" arise, which are at a distance from the wall of the Housing be ignited.
  • the invention is based on the object a method and a burner of the type mentioned create that work with reduced pollutant emissions.
  • a burner according to the invention by the measures of Claim 1 marked.
  • the mixture passage openings in the form of at least two Hole fields are arranged, which are in the longitudinal direction of the Extend housing, advantageously the distance between adjacent perforated fields 5 to 35 mm, preferably about 25 mm.
  • the wall of the housing that the mixture passage openings has is preferably the peripheral wall.
  • the perforated fields be formed in separate perforated strips that are free of thermal stress can be inserted into the wall of the housing.
  • the assignment of housing and injector and the design the housing are basically arbitrary. So can the injector be upstream of the housing. A particularly beneficial one
  • the housing is rod-shaped and the injector surrounds.
  • the injector can be a further development of the invention a downstream extension that is closed at the front have radial openings which the mixture passage openings opposite the wall of the housing are. This enables a particularly homogeneous mixture distribution, and with structurally simple means. The latter applies in particular if the extension of the injector extends to an end wall of the housing.
  • the invention further relates to a method for Operating an atmospheric, substoichiometric premixing gas burner according to one of the preceding Claims with an injector into which gas is injected, and with a housing fed by the injector, which Has mixture passage openings. This is a procedure according to the invention characterized by claim 9.
  • the air ratio preferably remains when the Gas supply up to about 50% of the nominal heat load of about 50% essentially unchanged. This contributes significantly to the increase the flame stability.
  • the flame speed changes only around 20%, so that gases with different Properties can be easily burned.
  • the Burner according to the invention a rod-shaped housing 1, which surrounds an injector 2.
  • the injector is a nozzle 3 assigned, which sits on a nozzle holder 4.
  • the latter is with an associated end wall 5 connected.
  • the injector has one tubular extension 6 that extends up to one associated end wall 7 extends and closed by the latter becomes.
  • the housing 1 is in the upper Provide area with mixture passage openings 8. This have a diameter of 0.8 mm and are with a Perforation degree of 26% arranged hexagonally, being two Form perforated fields that extend in the longitudinal direction of the housing 1 extend. The distance between the two perforated fields is 25 mm.
  • the perforated fields are formed in separate perforated strips 9, which in the upper area of the housing 1 in its wall are used.
  • the wall of the housing 1 longitudinal guides 10 into which the perforated strips 9 in axial Direction are inserted. This will be between the paper tape and the peripheral wall of the housing creates a seal, which also strikes back when thermal expansion occurs prevents the flame and tension cracks in the paper tape.
  • the seals in the axial direction serve webs 11, which overlap the punched tape 9. This holder is also free of thermal stress.
  • the perforated strips 9 form the only perforated to be processed Parts and consist, in contrast to the other housing sections, made of highly heat-resistant chrome-aluminum steel.
  • the gas emerging from the injector 2 becomes very uniform distributed to the mixture passage openings 8. This is provide the extension 6 of the injector with radial openings 12, however only in the mixture passage openings 8 opposite area, i.e. in the lower area.
  • the burner is operated premixing under-stoichiometrically, with an exit surface load of 150 W / cm 2 and an air ratio of 0.8. It shows very favorable pollutant behavior by optimizing CO and NO x emissions on the one hand.
  • the flame stability is very good and enables the combustion of gases with different properties.
  • the webs 11 are only arranged on the end walls 5 and 7 of the housing 1.
  • the modified embodiment according to FIG. 4 differs of this in that the punched tape 9 in the longitudinal direction are divided, with central webs 11 facing towards the center Pick up ends of punched tape 9.
  • This construction is recommended if the punched tape 9 is relatively long are and made of particularly thin material with a thickness of preferably 0.5mm. Even under these circumstances, you can then thermal loads do not lead to impermissible faults the punched tape 9 lead. The sealing on the butt edges is ensured by the central webs 11.
  • the burner according to the invention can in a not shown Combustion chamber can be arranged, preferably with a secondary air slot located below the burner is provided.
  • the latter extends parallel to the burner preferably over a length which corresponds to the length of the perforated strips 9 corresponds.
  • the secondary air hits the housing 1 from below of the burner, flows around the housing and enters the side flame carpets carried by the perforated strips 9. On this results in optimal combustion conditions.
  • the housing can be designed differently than rod-shaped be. Nor does it have to surround the injector, but rather can be connected after this. Furthermore, with three or more Perforated fields or with only one perforated field, each perforated field being integrally connected to the wall of the housing can be. The latter also ensures a seal against the flames fighting back.

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)

Claims (10)

  1. Brûleur à gaz atmosphérique assurant un mélange préalable sous-stoechiométrique, comprenant un injecteur (2) et un boítier (1) associé axialement à l'injecteur, ledit boítier comportant des ouvertures de traversée de mélange (8) dans une paroi, caractérisé en ce que les ouvertures de traversée de mélange possèdent un diamètre de 0,5 à 1,2 mm, de préférence environ 0,8 mm, et sont ménagées avec un taux de perforation de 15 à 30% en au moins un champ de perçages (9) réalisé sous forme d'une bande de perçages particulière (9), et en ce que le ou chaque champ de perçages (9) est mis en place dans le boítier (1) d'une manière exempte de contrainte thermique.
  2. Brûleur selon la revendication 1, caractérisé en ce que les ouvertures de traversée de mélange sont agencées sous la forme d'au moins deux champs de perçages qui s'étendent en direction longitudinale du boítier (1), lesdits champs de perçages étant réalisés dans des bandes de perçages particulières (9) qui sont mises en place dans la paroi du boítier (1) d'une manière exempte de contrainte thermique.
  3. Brûleur selon l'une ou l'autre des revendications 1 et 2, caractérisé en ce que la distance entre des champs de perçages voisins s'élève de 5 à 35 millimètres, de préférence à environ 25 millimètres.
  4. Brûleur selon l'une des revendications 1, 2 ou 3, caractérisé en ce que la ou chaque bande de perçages (9) est constituée en un matériau résistant à des hautes températures, en particulier en acier au chrome et à l'aluminium.
  5. Brûleur selon l'une des revendications 1 à 4, caractérisé en ce que la ou chaque bande de perçages (9) est susceptible d'être enfilée dans des guidage latéraux (10) de la paroi du boítier (1), qui s'étendent longitudinalement, et leurs extrémités s'engagent de préférence dans des barrettes en chevauchement (11).
  6. Brûleur selon l'une des revendications 1 à 5, caractérisé en ce que le boítier (1) est réalisé sous forme de tige, et en ce qu'il entoure l'injecteur (2).
  7. Brûleur selon la revendication 6, caractérisé en ce que l'injecteur (2) présente un prolongement (6) disposé à l'écart de l'écoulement et refermé du côté frontal, avec des ouvertures radiales (12) qui sont opposées aux ouvertures de traversée pour le mélange (8) dans la paroi du boítier (1), ledit prolongement (6) de l'injecteur (2) s'étendant de préférence jusqu'à une paroi frontale (7) du boítier (1).
  8. Brûleur selon l'une des revendications 1 à 7, caractérisé en ce que, dans une chambre de combustion qui l'entoure, il est prévu une fente d'air secondaire au-dessous du brûleur et s'étendant parallèlement à celui-ci.
  9. Procédé d'utilisation d'un brûleur à gaz atmosphérique qui assure un mélange préalable sous-stoechiométrique, selon l'une des revendications précédentes, au moyen d'un injecteur dans lequel on souffle le gaz, et comprenant un boítier dans lequel est situé l'injecteur, ledit boítier comportant des ouvertures de traversée pour le mélange,
    caractérisé en ce que la charge superficielle, en relation à la section de traversée libre pour le mélange, s'élève de 110 à 210 W/cm2, de préférence 130 à 170 W/cm2, et en ce que le taux d'air est réglé de 0,7 à 0,9, de préférence de 0,75 à 0,85.
  10. Procédé selon la revendication 9, caractérisé en ce que, lors d'une réduction de l'amenée de gaz, le taux d'air reste sensiblement sans modification jusqu'à environ 50% de la charge thermique nominale.
EP92901135A 1991-01-07 1991-12-19 Bruleur a gaz et procede pour son utilisation Expired - Lifetime EP0519029B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE4100247A DE4100247A1 (de) 1991-01-07 1991-01-07 Gasbrenner und verfahren zu seinem betreiben
DE4100247 1991-01-07
PCT/EP1991/002454 WO1992012381A1 (fr) 1991-01-07 1991-12-19 Bruleur a gaz et procede pour son utilisation

Publications (2)

Publication Number Publication Date
EP0519029A1 EP0519029A1 (fr) 1992-12-23
EP0519029B1 true EP0519029B1 (fr) 1998-07-22

Family

ID=6422632

Family Applications (1)

Application Number Title Priority Date Filing Date
EP92901135A Expired - Lifetime EP0519029B1 (fr) 1991-01-07 1991-12-19 Bruleur a gaz et procede pour son utilisation

Country Status (4)

Country Link
EP (1) EP0519029B1 (fr)
AT (1) ATE168761T1 (fr)
DE (1) DE4100247A1 (fr)
WO (1) WO1992012381A1 (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT400183B (de) * 1993-09-24 1995-10-25 Vaillant Gmbh Verfahren zur minimierung der bildung thermischer stickoxide bei einer verbrennung
NL1001688C2 (nl) * 1995-11-17 1997-05-21 Furigas Assen Bv Brander met gesegmenteerd branderdek.
EP0844435A1 (fr) * 1996-11-26 1998-05-27 Worgas Bruciatori S.R.L. Brûleur à gaz
US5743727A (en) * 1997-01-21 1998-04-28 Burner Systems International, Inc. Premixed gas burner
ATE246782T1 (de) * 1999-03-18 2003-08-15 Worgas Bruciatori Srl Rohrbrenner
DE10010762C2 (de) * 2000-03-04 2002-03-28 Bosch Gmbh Robert Atmosphärischer Gasbrenner

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1596452A (en) * 1924-11-13 1926-08-17 Ironton Stove & Mfg Co Gas burner
DE1983128U (de) * 1968-01-09 1968-04-11 Heinrich Goesser Soehne Lang- und rundbrenner fuer alle gebraeuchlichen brennbaren gase.
DE2132968A1 (de) * 1970-07-04 1972-01-13 Guiseppe Fogliani Gasbrenner
GB1442758A (en) * 1972-10-11 1976-07-14 British Gas Corp Gas burners
US3936003A (en) * 1973-12-03 1976-02-03 Raytheon Company Multiport high density burner
NL7503775A (nl) * 1975-03-27 1976-09-29 Burnham Europa Bv Gasbrander voorzien van een branderlichaam met schuifplaat.
GB1517957A (en) * 1975-07-24 1978-07-19 Aeromatic Co Ltd Aerated gas burner
DE3113416A1 (de) * 1981-04-03 1982-10-21 Ruhrgas Ag, 4300 Essen Verfahren zum betrieb eines einem luftstrom ausgesetzten gasbrenners sowie brenner zur durchfuehrung des verfahrens
DE8605654U1 (de) * 1986-03-01 1987-07-02 Ruhrgas Ag, 4300 Essen Brenner für gasförmige Brennstoffe
DE3787810T2 (de) * 1987-08-03 1994-04-14 Worgas Bruciatori Srl VERBRENNUNGSVERFAHREN UND GASBRENNER MIT NIEDRIGER NOx-, CO-EMISSION.
DE3914222A1 (de) * 1988-05-11 1989-11-23 Wolf Klimatechnik Gmbh Heizkessel mit atmosphaerischem brenner und optimierter sekundaerluftzufuehrung

Also Published As

Publication number Publication date
DE4100247A1 (de) 1992-07-09
WO1992012381A1 (fr) 1992-07-23
ATE168761T1 (de) 1998-08-15
EP0519029A1 (fr) 1992-12-23
DE4100247C2 (fr) 1993-01-21

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