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WO1991006804A1 - BRULEUR ET PROCEDE DE REDUCTION DE LA FORMATION DE NO¿x? - Google Patents

BRULEUR ET PROCEDE DE REDUCTION DE LA FORMATION DE NO¿x? Download PDF

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Publication number
WO1991006804A1
WO1991006804A1 PCT/SE1990/000708 SE9000708W WO9106804A1 WO 1991006804 A1 WO1991006804 A1 WO 1991006804A1 SE 9000708 W SE9000708 W SE 9000708W WO 9106804 A1 WO9106804 A1 WO 9106804A1
Authority
WO
WIPO (PCT)
Prior art keywords
oxygen
nozzle
fuel
jet
burner
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.)
Ceased
Application number
PCT/SE1990/000708
Other languages
English (en)
Inventor
Lars Saltin
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.)
Linde Sverige AB
Original Assignee
AGA 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 AGA AB filed Critical AGA AB
Publication of WO1991006804A1 publication Critical patent/WO1991006804A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

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
    • F23D14/32—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid using a mixture of gaseous fuel and pure oxygen or oxygen-enriched air
    • 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
    • F23D11/24—Burners using a direct spraying action of liquid droplets or vaporised liquid into the combustion space by pressurisation of the fuel before a nozzle through which it is sprayed by a substantial pressure reduction into a space
    • 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

Definitions

  • the present invention relates to a method of burning fossil fuel, preferably gas or liquid fuel, and particular, but not exclusively, fuel oil, with oxygen with the intention of reducing the amount of nitrogen oxides formed with this combustion, and also to a burner for carrying out the method.
  • fossil fuel preferably gas or liquid fuel, and particular, but not exclusively, fuel oil
  • liquid fuel e.g. fuel oil
  • the liquid fuel can be finely divided with the aid of a gaseous medium.
  • the medium used is normally air or steam.
  • gases can also be used, however, such as natural gas, propane and carbon dioxide, for instance.
  • compressed air is the gas that is most often used for economic reasons, this air being delivered at a pressure of, e.g. 2-5 bars, so as to finely divide the liquid fuel at the moment of its exit from the burner nozzle.
  • the supply of air, and also to a lesser extent the supply of natural gas, results in the introduction of nitrogen to the combustion process, since nitrogen is present in natural gas.
  • the actual fuel oil itself may contain up to 0.5% by weight nitrogen. This nitrogen reacts with the oxygen supplied to sustain combustion, therewith resulting in the production of nitrogen oxides, normally nitrogen monoxide and nitrogen dioxide.
  • One object of the present invention is to provide a method and a device for combusting fossil fuels in a manner which will avoid the formation of nitrogen oxides to the greatest possible extent, irrespective of whether nitrogen is present naturally in the fuel or is supplied thereto sepa ⁇ rately, for instance in the form of air.
  • Another object is to provide a method of combusting liquid, fossil fuels without supplying atomized substances to the fuel, and to provide a device for carrying out the method.
  • This primary object is achieved with a method in which the fuel is delivered to a combustion zone from a central exit nozzle, in which oxygen is supplied at a low speed in the form of at least one first jet located at a first radial distance from the central fuel jet, and in which oxygen is delivered at high velocity in the form of at least one second jet at a second radial distance from the central fuel jet, wherein said second distance is greater than said first distance, for the purpose of generating incomplete combustion of the fuel with the oxygen of low speed in a first region and complete combustion with the oxygen of high speed in a second region downstream of the first region, said regions together forming the combustion zone.
  • the burner used for carrying out the method includes a central exit nozzle for delivering fuel to a combustion zone, and is characterized by at least one first oxygen nozzle which is arranged at a first radial distance from the central exit nozzle and which delivers oxygen at a low speed, and at least one second oxygen nozzle which is arranged at a second radial distance from the central exit nozzle and which delivers oxygen at a high speed, said second distance being greater than said first distance, such as to generate incomplete combustion of the fuel with the oxygen of low speed in a first region and complete combustion of the fuel with the oxygen of high speed in a second region downstream of the first region, said regions together forming the combustion zone.
  • liquid fuel e.g. fuel oil
  • the fuel is caused to leave the central nozzle in the form of a conical mantle, wherein the fuel is finely divided or atomized, and the radial extension of the conical fuel jet is restricted with the aid of an annular third oxygen jet located at shorter radial distance from the central exit nozzle than th first oxygen jet.
  • the burne includes a central nozzle which delivers the fuel in the for of a conical mantle, wherein the fuel is finely divided o atomized, and is characterized by at least one third oxyge nozzle which is arranged radially between the central exi nozzle and the first oxygen nozzle and which delimits th radial extension of the conical fuel nozzle.
  • Figure 1 is a schematic sectional view along the lon ⁇ gitudinal axis of the inventive burner
  • Figure 2 is a schematic sectional view, in larger scale, of the forward part of the burner in Figure 1; and Figure 3 is a schematic view from the front of the inventive burner.
  • the burner 1 in Figures 1-3 comprises a casing 12 which delimits a cylindrical oxygen chamber 16 and which is surrounded, at least at its forward part, by a cylindrical cooling jacket 13 having a cooling agent inlet 14 and a cooling agent outlet 15, this cooling agent normally being water.
  • the rear part of the casing 12 is provided with a flange 17 to which a wall 18 defining the oxygen chamber 16 is sealingly attached with the aid of a number of bolts, for instance, not shown.
  • Connected to the oxygen chamber 16 is an inlet 19 for oxygen-containing gas, preferably pure oxygen.
  • the casing 12 functions as the inner wall of the cooling jacket 13 surrounding the burner, at the forward end of said burner.
  • the burner 1 also includes a center body 9 which is arranged in the forward part of the burner.
  • the center body 9 forms the forward limitation of the oxygen chamber 16.
  • the center body 9 has a forward part 8 having a diameter such that said body will sealingly abut the inner surface of the casing 12.
  • the cylindrical mantle surface of the forward part 8 may be configured with a groove for accommodating an O-ring 20.
  • the center body 9 also has a rear part 7 whose axial length is longer but whose radius is smaller than the forward part 8. There is formed between the rear part 8 of the center body 9 and the casing 12 an annular gap which extends up to the forward part 8, which forms an annular end wall 9 and thus a forward defining wall 8 of the oxygen chamber 16.
  • This annular end wall 8 is provided with a plurality of openings 6 which widen conically in the direc ⁇ tion of the burner and which are preferably laval nozzles. These openings 6 are disposed concentrically in a ring and are spaced at regular distances apart.
  • a fuel line 21 extends through the center of the end wall 18.
  • the fuel line 21 extends through the whole of the oxygen chamber 16 and opens into the center body 9, where the forward end of said fuel line terminates in a fuel nozzle 5.
  • the fuel nozzle 5 is the center nozzle of the burner 1.
  • the center body 9 is also provided with a number of channels which extend axially through the whole body. These channels have a circular cross-section and comprise a first rearward part 4 and a second forward part 3, this latter channel part having a larger diameter than the rear channel part.
  • the rear channel part 4 functions as a constriction for the forward channel part 3, which forms an oxygen nozzle.
  • the forward circular area of the center body 9 is spaced from the forward end of the casing 12.
  • the distance from the forward end of the casing 12 or the cooling jacket 13 to the forward side of the center body 9 is normally 0.5-1.5 times the internal diameter of the casing.
  • cooling water is delivered through the inlet 14 and flows through the cooling jacket 13 and is discharged through the outlet 15.
  • a gaseous fuel for instance natural gas
  • Oxygen is delivered through the inlet 19 to the oxyge chamber 16, where a pressure of up to 5 bars is built up.
  • Th oxygen leaves the chamber 16 partly through the opening 6 i the forward, wall-like part 8 of the center body 9 and partl through the channels 4, and thereafter through the channel 3 forming the oxygen nozzles 3.
  • the respective diameters o the channel 4 and channel 3 are selected so that the oxyge leaves the oxygen nozzle 3 at a speed of 50-150 meters pe second, preferably about 100 meters per second or lower.
  • the peripheral oxygen nozzles 6 are configured so tha oxygen leaves these nozzles at supersonic speed, i.e. at speed of from 350-500 meters per second. These nozzles will preferably form laval nozzles.
  • the size of the channels 4 and the peripheral oxyge nozzles, and also the number of such channels and nozzles is selected so that about 25-75 percent of the oxygen will leave the oxygen chamber 16 through the openings 3.
  • the remaining part of said oxygen leaves the oxygen chamber through the peripheral nozzle 6.
  • the oxygen flowing through the laval nozzles 6 moves at high speed and is located radially further away from the nozzle than the oxygen which exits from the openings 3. Consequently, this oxygen will come into peripheral contact with residual fuel, and also the reaction products, in an axial direction more distal from the burner than the first combustion zone and form a second combustion zone. These combustion zones normally overlap one another, i.e. they merge with one another and a total combustion zone. Due to the high speed of the peripheral oxygen, ambient atmosphere will be drawn into the oxygen which is therewith diluted and the flame or reaction temperature consequently lowered. Consequently, the reaction rate at which nitrous gases, NO x , are formed will be lower. The nitrogen consumed in forming these nitrous gases may come from the ambient atmosphere or from the fuel. Oxygen is supplied to the burner in an amount corresponding to substantially stoichiometric combustion, preferably with a small oxygen surplus of at most 5-10 percent.
  • the inventive burner is intended for burning fuel oil or some other liquid fuel.
  • This third nozzle 24 is configured as an annular channel in the center body 9, this channel surrounding the fuel nozzle 5 con ⁇ centrically and being located at a shorter distance from the center axis of the burner 1 than the oxygen nozzle 3.
  • the rear part of this third oxygen nozzle is connected with the oxygen chamber 16 and consists in an annular channel 25 and has a relatively large width exten ⁇ sion.
  • the channel 25 merges with a channel 26 of smaller width in the center body 9.
  • the width and diameter of the channel 25 are so adapted that 5-10 percent of the oxygen delivered to the oxygen chamber 16 exits through the nozzle 24.
  • the fuel nozzle delivers the liquid fuel in the form of a conical mantle or spray.
  • the fuel is supplied to the line 19 at a pressure of 20-30 bars.
  • the fuel leaves the nozzle 5 in the form of a conical spray or mantle, the cone angle being dependent on the nozzle configuration.
  • the fuel is therewith finely divided into discrete liquid droplets or is atomized. It is particularly preferred to configure the nozzle 5 so that the fuel is given a swirling motion as it exits from the nozzle.
  • the oxygen exiting from the third, annular nozzle 24 will preferably flow in the form of a hollow cylinder externally of the diverging fuel jet and impinges on said jet at a distance from the forward side 8 of the center body 9.
  • the oxygen jet exiting from the nozzle 24 may also diverge slightly.
  • the oxygen jet exiting from the third nozzle 24 is given an annular cross-sectional shape in order to limit the radial propagation of the fuel.
  • the embodiment which includes the third nozzle may also be used for gaseous fuel.
  • the peripheral oxygen nozzle 6 may be replaced with an annular oxygen nozzle having a width which widens in the forward direction of said nozzle.
  • the annular nozzle is preferably configured so that at least substantially the same flow profile is obtained as that obtained through a laval nozzle.
  • the nozzles 3 through which oxygen exits at a low speed may also be replaced with an annular nozzle. These nozzles are configured so that the oxygen will leave the burner in at least substantially mutually parallel jets parallel with the burner center line.
  • the inventive burner can be used with liquid fuel without using, for instance, air for atomizing the fuel. Because lower flame temperatures are obtained when using the inventive burner, the formation of nitrous gases due to the presence of nitrogen in the fuel and the supply of air is suppressed.
  • oxygen is to be interpreted as an oxygen containing gas containing at least 90 per cent by volume of oxygen, preferably at least 95 per cent by volume of oxygen. It is especially preferred that the gas contains at least 99 per cent by volume of oxygen.
  • oxygen nozzle is meant to define a nozzle for the oxygen containing gas comprising at least 90 per cent by volume of oxygen.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Combustion Of Fluid Fuel (AREA)
  • Nozzles For Spraying Of Liquid Fuel (AREA)

Abstract

Procédé et brûleur de combustion de combustible à l'aide d'oxygène, le combustible étant acheminé jusqu'à une zone de combustion à partir d'un ajutage (5) de sortie central. L'oxygène se déplaçant à vitesse lente est acheminé d'un premier ajutage (3) d'oxygène, à une première distance radiale du jet de combustible central, et l'oxygène se déplaçant à vitesse rapide est acheminé à partir d'un second ajutage (6) d'oxygène, à une seconde distance radiale supérieure du jet de combustible central. Cet agencement a pour résultat une combustion incomplète du combustible à l'aide de l'oxygène se déplaçant à vitesse lente dans une première région, et une combustion incomplète à l'aide de l'oxygène se déplaçant à vitesse rapide dans une seconde région, en aval de la première région, ces régions formant ensemble la zone de combustion.
PCT/SE1990/000708 1989-11-01 1990-10-31 BRULEUR ET PROCEDE DE REDUCTION DE LA FORMATION DE NO¿x? Ceased WO1991006804A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8903654-5 1989-11-01
SE8903654A SE464542B (sv) 1989-11-01 1989-11-01 Saett och anordning foer foerbraenning av foeretraedesvis flytande eller gasformigt fossilt braensle

Publications (1)

Publication Number Publication Date
WO1991006804A1 true WO1991006804A1 (fr) 1991-05-16

Family

ID=20377357

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Application Number Title Priority Date Filing Date
PCT/SE1990/000708 Ceased WO1991006804A1 (fr) 1989-11-01 1990-10-31 BRULEUR ET PROCEDE DE REDUCTION DE LA FORMATION DE NO¿x?

Country Status (2)

Country Link
SE (1) SE464542B (fr)
WO (1) WO1991006804A1 (fr)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2271419A (en) * 1992-01-13 1994-04-13 Harry Hammond Pure oxygen enhanced furnace firing
EP0614044A3 (fr) * 1993-03-01 1994-11-09 Air Prod & Chem Procédé et dispositif pour l'atomisation et la vaporisation des combustibles liquides améliorés par le combustion.
EP0644374A3 (fr) * 1993-09-15 1995-09-06 Boc Group Inc Brûleur oxy-combustible et procédé d'utilisation.
WO1997007364A1 (fr) * 1995-08-21 1997-02-27 Cheyuan Chang Four a gaz avec un moyen d'alimentation en comburant
EP0663562A3 (fr) * 1994-01-13 1997-06-04 Messer Griesheim Gmbh Procédé et brûleur pour la réduction des émissions des gaz nocifs pendant la combustion.
WO1998025076A1 (fr) 1996-12-04 1998-06-11 Voest-Alpine Industrieanlagenbau Gmbh Bruleur pour la combustion de combustibles solides finement granulaires a pulverulents
FR2757844A1 (fr) * 1996-12-26 1998-07-03 Air Liquide Procede de fabrication de verre technique et bruleur pour la mise en oeuvre d'un tel procede
US6142765A (en) * 1995-09-07 2000-11-07 Vost-Alpine Industrieanlagenbau Gmbh Process for burning fuel
CN113983463A (zh) * 2021-12-08 2022-01-28 北京瑞晨航宇能源科技有限公司 一种纯氧燃烧器及燃烧方法

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1261831A (en) * 1969-01-14 1972-01-26 Nippon Kokan Kk Improvements in burner devices
DE2324104B2 (de) * 1973-05-12 1975-10-16 Jean Nassheuer, Industrieofenbau Und Elektrotechnik, 5210 Troisdorf Scheibenbrenner für Strahlheizrohre
US4023921A (en) * 1975-11-24 1977-05-17 Electric Power Research Institute Oil burner for NOx emission control
GB1530260A (en) * 1976-02-05 1978-10-25 Central Electr Generat Board Oil fuel burners
EP0038257A1 (fr) * 1980-04-10 1981-10-21 Union Carbide Corporation Brûleur aspirateur à oxygène et procédé pour chauffer un foyer avec un gaz oxydant enrichi d'oxygène
SE439363B (sv) * 1979-03-05 1985-06-10 Steinmueller Gmbh L & C Brennare for kvevehaltiga brenslen
US4575332A (en) * 1983-07-30 1986-03-11 Deutsche Babcock Werke Aktiengesellschaft Method of and burner for burning liquid or gaseous fuels with decreased NOx formation
DE3541987A1 (de) * 1985-11-28 1987-06-04 Sonvico Ag Ing Bureau Brenner fuer fluessige und/oder gasfoermige brennstoffe
US4842509A (en) * 1983-03-30 1989-06-27 Shell Oil Company Process for fuel combustion with low NOx soot and particulates emission

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1261831A (en) * 1969-01-14 1972-01-26 Nippon Kokan Kk Improvements in burner devices
DE2324104B2 (de) * 1973-05-12 1975-10-16 Jean Nassheuer, Industrieofenbau Und Elektrotechnik, 5210 Troisdorf Scheibenbrenner für Strahlheizrohre
US4023921A (en) * 1975-11-24 1977-05-17 Electric Power Research Institute Oil burner for NOx emission control
GB1530260A (en) * 1976-02-05 1978-10-25 Central Electr Generat Board Oil fuel burners
SE439363B (sv) * 1979-03-05 1985-06-10 Steinmueller Gmbh L & C Brennare for kvevehaltiga brenslen
EP0038257A1 (fr) * 1980-04-10 1981-10-21 Union Carbide Corporation Brûleur aspirateur à oxygène et procédé pour chauffer un foyer avec un gaz oxydant enrichi d'oxygène
US4842509A (en) * 1983-03-30 1989-06-27 Shell Oil Company Process for fuel combustion with low NOx soot and particulates emission
US4575332A (en) * 1983-07-30 1986-03-11 Deutsche Babcock Werke Aktiengesellschaft Method of and burner for burning liquid or gaseous fuels with decreased NOx formation
DE3541987A1 (de) * 1985-11-28 1987-06-04 Sonvico Ag Ing Bureau Brenner fuer fluessige und/oder gasfoermige brennstoffe

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Vol. 8, No. 26, M273; & JP,A,58 184 412, 27-10-1983, (NIHON SANSO K.K.). *

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2271419A (en) * 1992-01-13 1994-04-13 Harry Hammond Pure oxygen enhanced furnace firing
EP0614044A3 (fr) * 1993-03-01 1994-11-09 Air Prod & Chem Procédé et dispositif pour l'atomisation et la vaporisation des combustibles liquides améliorés par le combustion.
EP0644374A3 (fr) * 1993-09-15 1995-09-06 Boc Group Inc Brûleur oxy-combustible et procédé d'utilisation.
EP0663562A3 (fr) * 1994-01-13 1997-06-04 Messer Griesheim Gmbh Procédé et brûleur pour la réduction des émissions des gaz nocifs pendant la combustion.
WO1997007364A1 (fr) * 1995-08-21 1997-02-27 Cheyuan Chang Four a gaz avec un moyen d'alimentation en comburant
US6142765A (en) * 1995-09-07 2000-11-07 Vost-Alpine Industrieanlagenbau Gmbh Process for burning fuel
WO1998025076A1 (fr) 1996-12-04 1998-06-11 Voest-Alpine Industrieanlagenbau Gmbh Bruleur pour la combustion de combustibles solides finement granulaires a pulverulents
FR2757844A1 (fr) * 1996-12-26 1998-07-03 Air Liquide Procede de fabrication de verre technique et bruleur pour la mise en oeuvre d'un tel procede
EP0850883A3 (fr) * 1996-12-26 1998-07-08 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Procédé de fabrication de verre technique et brûleur pour la mise en oeuvre d'un tel procédé
US6332340B1 (en) 1996-12-26 2001-12-25 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Process for manufacturing technical glass and burner for implementing such a process
CN113983463A (zh) * 2021-12-08 2022-01-28 北京瑞晨航宇能源科技有限公司 一种纯氧燃烧器及燃烧方法

Also Published As

Publication number Publication date
SE464542B (sv) 1991-05-06
SE8903654D0 (sv) 1989-11-01

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