EP0076036B1 - Verfahren und Vorrichtung zum Verbrennen von Brennstoff in Stufen - Google Patents

Verfahren und Vorrichtung zum Verbrennen von Brennstoff in Stufen Download PDF

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Publication number
EP0076036B1
EP0076036B1 EP82304508A EP82304508A EP0076036B1 EP 0076036 B1 EP0076036 B1 EP 0076036B1 EP 82304508 A EP82304508 A EP 82304508A EP 82304508 A EP82304508 A EP 82304508A EP 0076036 B1 EP0076036 B1 EP 0076036B1
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EP
European Patent Office
Prior art keywords
fuel
air
total
burner
reaction zone
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
Application number
EP82304508A
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English (en)
French (fr)
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EP0076036A1 (de
Inventor
Richard R. Martin
Kurt S. Jaeger
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.)
Zinklahoma Inc
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John Zink Co
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Publication date
Application filed by John Zink Co filed Critical John Zink Co
Publication of EP0076036A1 publication Critical patent/EP0076036A1/de
Application granted granted Critical
Publication of EP0076036B1 publication Critical patent/EP0076036B1/de
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    • 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
    • F23D14/20—Non-premix gas burners, i.e. in which gaseous fuel is mixed with combustion air on arrival at the combustion zone
    • F23D14/22—Non-premix gas burners, i.e. in which gaseous fuel is mixed with combustion air on arrival at the combustion zone with separate air and gas feed ducts, e.g. with ducts running parallel or crossing each other
    • 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 
    • F23C6/00—Combustion apparatus characterised by the combination of two or more combustion chambers or combustion zones, e.g. for staged combustion
    • F23C6/04—Combustion apparatus characterised by the combination of two or more combustion chambers or combustion zones, e.g. for staged combustion in series connection
    • F23C6/045—Combustion apparatus characterised by the combination of two or more combustion chambers or combustion zones, e.g. for staged combustion in series connection with staged combustion in a single enclosure
    • F23C6/047—Combustion apparatus characterised by the combination of two or more combustion chambers or combustion zones, e.g. for staged combustion in series connection with staged combustion in a single enclosure with fuel supply in stages
    • 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 
    • F23C2201/00—Staged combustion
    • F23C2201/20—Burner staging
    • 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 
    • F23C2201/00—Staged combustion
    • F23C2201/30—Staged fuel supply

Definitions

  • This invention relates to a method and apparatus for burning fuel resulting in low NO,, formation. More specifically, this invention relates to a staged fuel and air injection burner.
  • staged air type low NOx burner wherein the fuel is first burned in a deficiency of air in one zone producing a reducing environment that suppresses NO X formation and then the remaining portion of the air is added in a subsequent zone.
  • Staged fuel also has been suggested by Hitachi Zosen of Japan in brochure No. D-148 of July 1978 wherein all of the air and some of the fuel is burned in the first zone and then the remaining fuel is added in the second zone.
  • the presence of an over abundance of air in the first reaction zone acts as a diluent thus lowering the temperature and suppressing formation of NO X . It has also been proposed to recirculate flue gas to accomplish the lowering of the flame temperature.
  • a method for burning fuel-air mixture for a furnace chamber that will result in low NO x products of combustion comprising the steps of supplying, at a given instant of burning, a given total amount of pressurized fuel and a given total amount of air, the total amount of air being at least substantially stoichiometrically sufficient to burn the total amount of fuel supplied to a burner, is characterized in that a primary reaction zone is created in the burner that begins outside of the furnace chamber but extends into the furnace chamber by supplying a first portion of the total fuel and a portion of the total air which exceeds the stoichiometric requirements for burning the first portion of the total fuel, separately injecting the remaining portion of the total fuel and the remaining portion of the total air into the furnace chamber so as to create a substantially unconfined secondary reaction zone about and reacting with a substantial portion of the primary reaction zone, the remaining portion of the total air being less than the stoichiometric requirement to burn the remaining portion of the total fuel.
  • the fuel may be proportioned from about 40% to 60% to the primary reaction zone and then from about 60% to 40% to the second reaction zone while the air is proportioned from about 80% to 95% to the primary zone (preferably 90%) and from about 20% to 5% to the secondary zone (preferably 10%).
  • a fuel-air burner for a furnace chamber comprising an air-fuel mixing and injection burner housing attached to the furnace wall such that th.e downstream face of the burner housing terminates substantially adjacent an inner wall of the furnace chamber, means being provided to supply to the housing at a given instant of burning, a given total amount of fuel under pressure and a given total amount of air, the total amount of air being at least substantially stoichiometrically sufficient to burn the total amount of fuel supplied to the burner housing, means being provided to create a primary reaction burning zone that begins in an enclosed space upstream of the inner wall and extends downstream of the inner wall into the furnace chamber and at least one secondary fuel supply and injection nozzle disposed adjacent the enclosed space, is characterized by means for supplying, to the primary burning zone, a first portion of the total fuel and a portion of the total air which exceeds the stoichiometric requirements for burning the first portion of fuel thereto, at least one conduit through the burner housing located adjacent the enclosed space, the or each conduit, providing communication between the total air supply
  • the burner is indicated generally by the numeral 10.
  • This particular embodiment involves a primary burnertube 12 leading to a T-bar primary nozzle 14 along with a pair of secondary burner tubes 16 and secondary burner nozzles 18 all being supplied hydrocarbon fuel from a common source through tube 20.
  • the fuel exiting primary nozzle 14 enters the primary combustion zone 22 wherein it is burned in the presence of a significant stoichiometric excess of air flowing through the interior 24 of the burner and entering the primary reaction zone 22 through an annular space 26 surrounding the primary nozzle 14, as indicated by the presence of arrows.
  • the effluent from the primary reaction zone 22 enters a larger secondary reaction zone 28. Simultaneously, the fuel exiting the secondary nozzle 18 is mixed with air from the interior 24 of the burner 10 passing through annular conduits 30 surrounding burner tubes 16 and is then burned in the secondary reaction zone 28 in the presence of the effluent from the first reaction zone 22.
  • the orifices of the respective T-bar nozzle 14and secondary nozzles 18 are sized such that the fuel is proportioned between the primary reaction zone and the secondary reaction zone. Preferably from about 40 to about 60% of the fuel is directed through the primary nozzle 14 and the remaining fuel is directed to the secondary nozzles 18.
  • the cross-sectional area of the annular space 26 and the annular conduits 30 for conducting air to primary and secondary reaction zones are selectedsuch as to deliver about 80% to 95% of the total airto the primary reaction zone 22 and the remaining 20% to 5% of the total air to the secondary reaction zone 28.
  • Fig. 4 illustrates the directional characteristics of the orifices of each secondary nozzle 18. As illustrated, the five fuel ports 32 will issue a fan like sheet of fuel directed towards the effluent of the primary combustion zone.
  • FIG. 5 an alternate forced draft burner 10 is illustrated involving a single gas nozzle 34 that directs the fuel delivered through conduit 36 into the primary combustion zone 3.8 defined by the refractory walls 40 of the burner.
  • Riser pipes 42 fitted with orifice tips 44 extend through this refractory wall 40 such as to deliver the secondary fuel to the secondary combustion zone 46.
  • combustion air flows through the interior 48 of burner 10 into the primary zone 38 by way of annular conduit 49 and into secondary combustion zone 46 through annular openings 50.
  • Figs. 6, 7 and 8 illustrate the basic orifice or port configuration 52 of the secondary nozzles 44 including alternate angles of inclination (Fig. 7) towards the axial direction of the flow in the primary reaction zone 38.
  • Fig. 9 illustrates another alternate embodiment of a staged fuel and air burner 10 of the present invention wherein the particular burner is a flat flame design involving a pair of primary nozzles 54 and 56 each essentially adjacent to the refractory walls forming the primary reaction zone 58. Similar to the previous embodiments, secondary fuel conduits 60 and 62 pass through the refractory material such as to deliver fuel to the secondary reaction zone 64.
  • the tip drillings included three orifices and were oriented in the first series discharging vertically upward (parallel to the centerline of the burner), in the second series discharging at a small angle, e.g. 15° off vertical (towards the burner centerline) and in the third series discharging 30° off vertical (towards the burner centerline).
  • Each test series of each set of tips included variations of primary/ secondary fuel ratio and turned down tests.
  • Fig. 10 shows the graphs plotted as a result of the tests.
  • the burner was also fired on center gas only to establish the base point for non-staged operation of 80 ppm NO x .
  • the lowest NO,, levels were obtained with secondary orifices discharging parallel to the burner axis, but this set of tips also produces the highest level of combustibles.
  • Turn down on 30° tips was about 3:1 on a fifty/fifty fuel split and turn down on 15° tips was about 2:1 on a forty/sixty split. Flame appearance was generally good on all arrangements. From the data and test results it is readily apparent that the basic concept of staged air and fuel combustion is capable of producing NOX levels significantly lower than conventional combustion.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)

Claims (6)

1. Brennstoffluftbrenner für eine Ofenkammer mit einem Brennergehäuse zum Vermischen und zum Einspritzen der-Luft und des Brennstoffs, das so an der Ofenwandung angeordnet ist, daß die stromab weisende Seite des Brennergehäuses im wesentlichen im Bereich einer inneren Wandung der Ofenkammer endigt, wobei Einrichtungen, vorhanden sind, um zu einem angegebenen Zeitpunkt des Brennvorgangs dem Gehäuse eine vorbestimmte Gesamtbrennstoffmenge unter Druck und eine vorbestimmte Gesamtluftmenge zuzuführen, wobei die Gesamtluftmenge stöchiometrisch mindestens im wesentlichen ausreicht, um die gesamte dem Brennergehäuse zugeführte Brennstoffmenge zu verbrennen, und wobei Einrichtungen vorhanden sind, um eine primäre Reaktionsbrennzone zustande zu bringen, die in einem von der inneren Wandung eingeschlossenen, stromaufwärts gelegenen Raum beginnt und sich in die Ofenkammer hinein stromabwärts der inneren Wandung erstreckt, wobei mindestens eine sekundäre Brennstoffzufuhr vorhanden ist und wobei eine Einspritzdüse im Bereich des geschlossenen Raums angeordnet ist, gekennzeichnet durch eine Einrichtung zum Zuführen eines ersten Teils des Gesamtbrennstoffs (14, 34, 54, 56) in die primäre Brennzone sowie eines Teils der Gesamtluft (26, 49), der den stöchiometrischen Bedarf zum Verbrennen des ersten dazu gelieferten Brennstoffteils übersteigt, durch mindestens eine Leitung (30, 50), die sich im Bereich des eingeschlossenen Raums (22, 38, 58) durch das Brennergehäuse erstreckt, wobei die bzw. jede Leitung (30, 50) eine sich zwischen der Gesamtluftzufuhr und der Ofenkammer (28, 46, 64) erstreckende Verbindung darstellt, wobei eine sekundäre Brennstoffzufuhr (16, 42, 60, 62) und eine Einspritzdüse (18, 44) innerhalb der bzw. jeder Leitung (30, 50) so angeordnet ist, daß ringsherum eine Luftströmung entsteht, wobei die Einspritzdüse im Bereich der inneren Wandung des Brennergehäuses (40) endigt, durch Einrichtungen zum Zuführen des Restteils des Gesamtbrennstoffs an die sekundären Luftzufuhr (16, 42, 60, 62) und an die Einspritzdüse (18, 44), und durch Einrichtungen, die den Restteil der durch die um die Einspritzdüse (18, 44) angeordnete Leitung (30, 50) strömenden Gesamtluft so zuführt, daß der Restteil der Gesamtluft weniger ist als der stöchiometrische Bedarf zur Verbrennung des Restteils des Gesamtbrennstoffs, wobei die Einspritzdüse (18, 44) den Restteil des Gesamtbrennstoffs und den Restteil der Gesamtluft in eine Richtung strömen lässt, um zu der Entstehung einer im wesentlichen unbegrenzten sekundären Reaktionsbrennzone beizutragen, die sich um einen größeren Anteil des Ausflußes aus der primären Reaktionszone innerhalb der Ofenkammer (28,46,64) befindet und mit diesem Ausfluß reagiert.
2. Brenner nach Anspruch 1 dadurch gekennzeichnet, daß er Einrichtungen umfaßt, um ca. 40% bis ca. 60% des Gesamtbrennstoffs und ca. 60% bis ca. 40% des Brennstoffs der primären Reaktionszone bzw. der sekundären Reaktionszone zuzuführen.
3. Brenner nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß er Einrichtungen umfaßt, um ca. 80% bis ca. 95% der Gesamtluft der primären Reaktionszone zuzuführen.
4. Verfahren zum Verbrennen eines Brennstoffluftgemisches für eine Brennkammer, das Niedrig-NOx-Verbrennungsprodukte abgibt, worin man zu einem bestimmten Zeitpunkt eine vorbestimmte Menge des unter Druck stehendenden Gesamtbrennstoffs sowie eine vorbestimmte Gesamtluftmenge zuführt, wobei die Gesamtluftmenge im wesentlichen stöchiometrisch wenigstens ausreicht, um die dem Brenner zugeführte Gesamtbrennstoffmenge zu verbrennen, dadurch gekennzeichnet, daß innerhalb des Brenners eine primäre Reaktionszone entsteht, die außerhalb des Ofens beginnt und die sich in die Ofenkammer hinein erstreckt, indem ein erster Teil des Gesamtbrennstoffs und ein Teil der Gesamtluft zugeführt werden, der den stöchiometrischen Bedarf zum Verbrennen des ersten Teils des Gesamtbrennstoffs übertrifft, wobei der Restteil des Gesamtbrennstoffs sowie der Restteil der Gesamtluft in die Brennkammer getrennt eingespritzt werden, so daß eine im wesentlichen unbegrenzte sekundäre Reaktionszone um einen wesentlichen Teil der primären Reaktionzone herum entsteht und mit dieser Zone reagiert, wobei der Restteil der Gesamtluft weniger ist als der stöchiometrischen Bedarf zum Verbrennen des Restteils des Gesamtbrennstoffs.
5. Verfahren nach Anspruch 4 gekennzeichnet durch eine Aufteilung des Brennstoffanteils, der ca. 40% bis ca. 60% und ca. 60% bis 40% an die primäre bzw. an die sekundäre Zone ausmacht.
6. Verfahren nach Anspruch 4 oder 5 dadurch gekennzeichnet, daß bezogen auf die Gesamtluftmenge der Luftanteil in der primären Reaktionszone ca. 80% bis 95% beträgt.
EP82304508A 1981-09-28 1982-08-26 Verfahren und Vorrichtung zum Verbrennen von Brennstoff in Stufen Expired EP0076036B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US30641281A 1981-09-28 1981-09-28
US306412 1981-09-28

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EP0076036A1 EP0076036A1 (de) 1983-04-06
EP0076036B1 true EP0076036B1 (de) 1987-04-29

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EP82304508A Expired EP0076036B1 (de) 1981-09-28 1982-08-26 Verfahren und Vorrichtung zum Verbrennen von Brennstoff in Stufen

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EP (1) EP0076036B1 (de)
JP (1) JPS5875606A (de)
CA (1) CA1212617A (de)
DE (1) DE3276191D1 (de)

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3331989A1 (de) * 1983-09-05 1985-04-04 L. & C. Steinmüller GmbH, 5270 Gummersbach Verfahren zur verminderung der no(pfeil abwaerts)x(pfeil abwaerts)-emission bei der verbrennung von stickstoffhaltigen brennstoffen
FR2625295B1 (fr) * 1987-12-24 1990-04-13 Gaz De France Procede et appareil destines a assurer la combustion etagee d'un melange combustible-comburant diminuant la production d'oxydes d'azote
DK6789A (da) * 1988-03-16 1989-09-17 Bloom Eng Co Inc Fremgangsmaade og apparat til at undertrykke no dannelse i regenerative braendere.
GB8807859D0 (en) * 1988-04-05 1988-05-05 Nordsea Gas Technology Ltd Combination burners
GB8824575D0 (en) * 1988-10-20 1988-11-23 Airoil Flaregas Ltd Improvements in burner assemblies
NL8902963A (nl) * 1989-12-01 1991-07-01 Int Flame Research Foundation Werkwijze voor het verbranden van brandstof met een laag nox-gehalte in de verbrandingsgassen door middel van getrapte brandstoftoevoer en brander te gebruiken daarbij.
WO1992016792A1 (en) * 1991-03-15 1992-10-01 Radian Corporation Apparatus and method for combustion within porous matrix elements
US5201650A (en) * 1992-04-09 1993-04-13 Shell Oil Company Premixed/high-velocity fuel jet low no burner
JP2638394B2 (ja) * 1992-06-05 1997-08-06 日本ファーネス工業株式会社 低ＮＯｘ燃焼法
US5441404A (en) * 1993-01-29 1995-08-15 Gordan-Piatt Energy Group, Inc. Burner assembly for reducing nitrogen oxides during combustion of gaseous fuels
US5944503A (en) * 1998-05-20 1999-08-31 Selas Corporation Of America Low NOx floor burner, and heating method
PL344624A1 (en) * 1999-12-16 2001-06-18 Bloom Eng Co Inc Burner being feed with an air-fuel mixture
SE531957C2 (sv) * 2006-06-09 2009-09-15 Aga Ab Förfarande för lansning av syrgas vid en industriugn med konventionell brännare
RU2534189C2 (ru) * 2010-02-16 2014-11-27 Дженерал Электрик Компани Камера сгорания для газовой турбины(варианты) и способ эксплуатации газовой турбины
EP3078910B1 (de) * 2015-04-08 2020-02-12 Vysoké Ucení Technické V Brne Gasbrenner mit gestufter verbrennung

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Publication number Priority date Publication date Assignee Title
DE1229229B (de) * 1963-07-18 1966-11-24 Zink Co John Brenner fuer gasfoermige und fluessige Brennstoffe
US4004875A (en) * 1975-01-23 1977-01-25 John Zink Company Low nox burner
US4347052A (en) * 1978-06-19 1982-08-31 John Zink Company Low NOX burner
US4257763A (en) * 1978-06-19 1981-03-24 John Zink Company Low NOx burner
US4245980A (en) * 1978-06-19 1981-01-20 John Zink Company Burner for reduced NOx emission and control of flame spread and length

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Brochure No. D-148, July 1978 by HITACHI ZOSEN *

Also Published As

Publication number Publication date
DE3276191D1 (en) 1987-06-04
EP0076036A1 (de) 1983-04-06
JPS5875606A (ja) 1983-05-07
CA1212617A (en) 1986-10-14

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