EP0926434A1 - Stickoxidemissionsarmer Brenner mit Gasrückführung - Google Patents

Stickoxidemissionsarmer Brenner mit Gasrückführung Download PDF

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Publication number
EP0926434A1
EP0926434A1 EP98430027A EP98430027A EP0926434A1 EP 0926434 A1 EP0926434 A1 EP 0926434A1 EP 98430027 A EP98430027 A EP 98430027A EP 98430027 A EP98430027 A EP 98430027A EP 0926434 A1 EP0926434 A1 EP 0926434A1
Authority
EP
European Patent Office
Prior art keywords
air
burner
nozzle
outlet
fuel
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.)
Withdrawn
Application number
EP98430027A
Other languages
English (en)
French (fr)
Inventor
Jean Claude Pillard
Jean Claude Gauthier
Jacques Pizant
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.)
Entreprise Generale de Chauffage Industriel Pillard SA
Original Assignee
Entreprise Generale de Chauffage Industriel Pillard SA
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 Entreprise Generale de Chauffage Industriel Pillard SA filed Critical Entreprise Generale de Chauffage Industriel Pillard SA
Publication of EP0926434A1 publication Critical patent/EP0926434A1/de
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D1/00—Burners for combustion of pulverulent 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 
    • F23C9/00—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber
    • F23C9/003—Combustion apparatus characterised by arrangements for returning combustion products or flue gases to the combustion chamber for pulverulent fuel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
    • F23L7/00—Supplying non-combustible liquids or gases, other than air, to the fire, e.g. oxygen, steam
    • F23L7/002—Supplying water
    • F23L7/005—Evaporated water; Steam

Definitions

  • the present invention relates to a low emission burner of nitrogen oxide with recycled gas circuit.
  • the technical sector of the invention is the production of burners can use one or more fuels simultaneously or not, with special arrangements for air supply ducts and / or other gases.
  • the main application of the invention is its use in burners for rotary tube ovens, in which at least one fuel and primary combustion air are brought in at at least two concentric conduits arranged around a conduit central, the rest of the so-called secondary air is brought outside of these ducts.
  • these burners comprise at least two annular ducts supplying the primary air, one under form of a swirling air stream with components peripheral flow, and the other as an axial air stream having substantially axial flow components; which two primary air flow ducts are arranged radially at the outside of any fuel line including in particular at least an annular pulverized coal supply duct; and leads him central, inside which a feeding rod of at least starting fuel, is partially blocked by a flame stabilizer in the form of a flange surrounding its opening central where said rod opens, and having openings for the passage of a small part of the primary combustion air is at most 20% of this air, so that in the central area downstream said stabilizer, no significant combustion of the combustible, qualifying the said central dead zone: such a burner is described and claimed in European patent 421 903 published on April 10 1991 and filed by the same applicant as for the present invention.
  • the present invention can in fact be considered as a improvement made to such burners and more generally to all burner that can be described as modern comprising said conduits supply of fuel and primary combustion air representing a maximum of 15% of the total air, which ducts forming together a nozzle intended to be mounted on an orifice provided for this in the wall of the enclosure forming the hearth of the oven or chamber combustion, and around which secondary air is brought representing at least 85% of the total air and having a temperature of over 500 ° C.
  • the objective of the present invention is to reduce the formation of nitrogen oxides which are formed, either by the oxidation of nitrogenous compounds existing in the fuel and called NO X fuel, or in the combustion air itself by oxidation of nitrogen which occurs in the presence of atomic oxide or other oxidizing radicals, when the temperature is very high in the combustion furnace and qualified as thermal NO X ; which objective must be achieved by maintaining a good range for adjusting the burner operating speed with a stable flame.
  • the objective of the present invention is in fact to reduce, even more than by the devices known to date, the formation of NO X, both thermal and fuel for such burners comprising at least two substantially concentric fuel supply conduits and in primary combustion air representing at most 15% of the total air, which ducts together form a nozzle at the outlet of which the start of combustion can take place and around which secondary air is brought representing at least 85% total air and having a temperature of more than 500 ° C.: according to the present invention, this objective is achieved with a burner comprising at least four independent supply circuits, one of which feeds an annular duct surrounding all of said fuel and primary air supply ducts, inside which oxygen-depleted gas is injected, and outside which secondary air is brought, the inner edge of the outlet orifice of said annular duct being offset radially with respect to the outer edge of the outermost concentric duct of the nozzle by an annular hub with a thickness of at least 25 mm and from 3 to 8% of the diameter of said nozzle.
  • the outlet speed of the oxygen-depleted gas is lower than that V c of the primary air, and of the order of magnitude of that V a of the secondary air; in addition, the outlet opening of the annular duct may diverge and form an angle ⁇ of between 2 and 10 ° relative to the axis of the burner, and said oxygen-depleted gas is preferably recycled flue gas, or steam or a mixture of steam and fumes.
  • said burner can also have outside the duct protection outermost concentric and toward the outlet thereof, obstacles capable of deflecting and diverting the flow of current from the axis of the nozzle secondary air.
  • Such a smoke and or water vapor screen facilitates the creation of eddies between said depleted gas and this primary air, creating a stabilizing annular space maintaining the primary air and the fuel inside the guide thus formed and delaying its mixing with the secondary air all the more.
  • Water vapor by creating a heat shield, enhances the effect of insulation between primary air and secondary air by delaying their mix, all the better since it does not consume energy unlike water spray.
  • Figure 1 is a simplified longitudinal sectional view of a burner according to the invention.
  • Figure 2 is a sectional view of another embodiment of a burner according to the invention.
  • Figure 3 is a front view of a type of burner of the Figure 1 and 2 with a continuous annular duct.
  • Figures 4a and 4b are front views of the same burners of Figures 1 and 2 as for Figure 3 but with an annular duct discontinuous.
  • Figure 5 is a longitudinal sectional view of a burner according to the invention and used as an improvement of a burner such as described in patent EP421903.
  • Figure 6 is a simplified perspective view in cutaway of a powder fuel supply line to create separate flames, completing a particular embodiment of a burner according to the invention.
  • the present invention applies to any burner comprising at at least two substantially concentric supply lines fuel and primary combustion air representing at most 15% of the total air, which ducts together form a nozzle 1 with an axis XX 'as shown in Figures 1 to 4 by a simple cylinder of diameter D and specified in a particular embodiment on the figure 5.
  • Combustion 2 therefore takes place downstream from the outlet of this nozzle 1 around which is brought the secondary air 3 representing at least 85% of the total air and having a temperature of more than 500 ° C.
  • a general external representation of an example of a complete burner can be viewed according to Figure 1 of European patent EP421903.
  • such a burner comprises at least four independent supply circuits, one of which supplies an annular duct 4 surrounding the assembly 1 of said fuel and primary air supply ducts, inside which is injected oxygen-depleted gas, and outside of which the secondary air is brought 3.
  • the internal edge 5 1 of the outlet orifice 5 of said annular duct 4 is offset radially with respect to the external edge 6 1 of the concentric duct the more external of the nozzle 1 by an annular hub 6 of thickness "d" of at least 25 mm and from 3 to 8% of the diameter D of the said nozzle 1 in order to generate a ripple by the creation of Karman vortex, all by not being too thick to avoid problems of fouling of the external surface of the hub 6 and too great a break in aerodynamic flow which could go against the desired goal; a person skilled in the art taking cognizance of the effect sought by the present invention is able to determine the characteristics of said annular hub 6 without it being necessary to give all the explanations in this description.
  • the outlet port 5 of the conduit annular 4 can diverge and form an angle ⁇ between 2 and 10 ° relative to the axis XX 'of the burner in order to spread the air even more secondary 3 and thus delay its mixing with that constituted by the primary air and the fuel supplied by the conduits of the nozzle 1.
  • the outlet orifice of said annular duct 5 can also be concentric without divergence with respect to the XX 'axis.
  • the exit velocity V g of the gas depleted in oxygen or smoke is of the order of magnitude that that V a of secondary air 3, that is to say from 10 to 50 meters per second, preferably of the order of 15 meters per second, which is significantly lower than that V c of the primary air which is supplied at a sufficiently high pressure to obtain an outlet speed of the order of 150 to 200 meters per second, or in general of the order of 170 meters per second.
  • the definition of oxygen-depleted gas is that of a gas composed of less than 21% oxygen: it can therefore be the recycled smoke gas leaving the combustion chamber where the burner according to the invention is located, or smoke gas from other sources, or even water vapor, or a mixture of steam and smoke.
  • the outlet orifice 5 of said annular duct 4 can be a continuous open crown as shown in FIG. 3 or discontinuous and have several openings, either rectangular in shape over the entire thickness e of duct 4 such as shown in Figure 4a, either in the form of orifices 5 2 of rounded shape, such as circular, shown in Figure 4b.
  • the nozzle 1 of axis XX ′ is that described in patent EP421903 already mentioned previously, and constituting a preferred embodiment of the burner according to the invention: the outlet orifices of the primary air supply conduits are arranged radially outside any outlet of the fuel conduit, both by the rod 10 located in the axis of the central conduit 8 as by the peripheral conduit 9 into which is preferably sent pulverized coal.
  • Said outlet orifices supply the nozzle 1 with axial air and swirling air through at least two concentric ducts 12, 13 and the central duct 8, inside which is positioned a nozzle holder 10, is partially blocked by a stabilizer of flame 8 in the form of a flange surrounding its central opening 10 1 where said nozzle holder 10 opens; said flame stabilizer 8 has openings for the passage of part of the primary combustion air, ie at most 20% of this air, so that, in the central zone 2 1 located downstream of said stabilizer 8, does not produces no significant combustion of the fuel qualifying said central zone 2 1 as dead.
  • the quantity of primary air sent to said central dead zone 2 1 is between 1% and 20% of the total primary air and preferably less than 10%, and the proportion of primary combustion air is between 2 and 10% of the total combustion air and preferably less than 6%.
  • the flame stabilizer 8 is preferably axially offset behind the set of concentric openings of outlet of primary air and solid or gaseous fuels.
  • the flame stabilizer 8 is disposed at the front end of a nozzle holder 10 inside which is in fact a liquid fuel supply rod, essentially used for starting the burner.
  • the axial air outlet opening 13 is the one located radially as far outside as possible from the set of primary air supply conduits and has an outer edge 14 which projects axially forward and constitutes the internal edge 6 1 of the hub 6 separating it from the external channel 4 of oxygen-depleted gas.
  • the secondary air itself can also be staggered by adding outside the protection 7 of the outermost concentric duct, in fact that 4 of the supply of smoke or depleted gas in oxygen, and towards the outlet orifice 5 thereof, obstacles 7 1 capable of deflecting and deviating from the axis XX 'of the nozzle 1 the flow of the secondary air current 3; such obstacles 7 1 can form a continuous crown in the form of a cone diverging from the external continuous surface of the protection 7 or consist of separate blocks forming a notched crown from the front.
  • oxygen-depleted gas such as smoke and / or water vapor
  • Said burner has at least two obstacles 67 for this, such as shown in Figures 5 and 6, provided in the conduit fuel supply 9, and which divide it into at least two channels in the vicinity of the outlet of this conduit, i.e. of the burner nozzle 1, so as to cause the separation of the incident vein of solid fuel in at least two veins for allow the formation of at least two flames.
  • said conduit 9 for supplying solid fuel has an upstream part located on the right in these figures, which is provided an annular cross section; due to the presence, such as represented in FIG. 6, of five obstacles 67 in the form of a profiled wedge triangular, the conduit 9 is divided into five channels 91, 92, 93, 94, 95 which are each delimited by, on the one hand, the external face 66A of the wall 66 separating the conduit 9 from the conduit 11, on the other hand the internal face 68A of the wall 68 separating the conduit 9 from the conduit 12, and also faces lateral 73 obstacles 67 in the form of a wedge; these extend to from their tapered or profiled rear end 70, and their section transverse widens or increases from their leading edge 70 to their terminal section 71 corresponding to the end or front face of the nozzle.
  • a section of substantially constant passage of solid fuel between the part upstream of the completely annular section duct and the downstream part fitted with obstacles 67 and divided into five channels the internal radius of the vein remains constant for example due to a cylindrical surface 66A, the external radius 61 corresponding to the radius of the face 68A external to the vicinity of the outlet openings of channels 91 to 95, is greater than radius 60 of the upstream part of the duct 9 of annular section, in order to compensate for the reduction in free cross-section resulting from the presence of these obstacles 67.
  • the height (measured radially) of the separate channels 91 to 95 by said obstacles 67 of the fuel supply duct 9 solid is then more important than the height of the part of the duct located upstream of obstacles.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
EP98430027A 1997-12-24 1998-12-04 Stickoxidemissionsarmer Brenner mit Gasrückführung Withdrawn EP0926434A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9716740 1997-12-24
FR9716740A FR2772887B1 (fr) 1997-12-24 1997-12-24 Bruleur a faible emission d'oxyde d'azote avec circuit de gaz recycle

Publications (1)

Publication Number Publication Date
EP0926434A1 true EP0926434A1 (de) 1999-06-30

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EP98430027A Withdrawn EP0926434A1 (de) 1997-12-24 1998-12-04 Stickoxidemissionsarmer Brenner mit Gasrückführung

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EP (1) EP0926434A1 (de)
FR (1) FR2772887B1 (de)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2453223A (en) * 2007-09-28 2009-04-01 Gen Electric Gas flow injector and method of injecting gas into a combustion system
CN105299678A (zh) * 2015-11-09 2016-02-03 广西桂晟新能源科技有限公司 一种将循环水蒸气应用于煤燃烧锅炉的方法
CN105351961A (zh) * 2015-11-09 2016-02-24 广西桂晟新能源科技有限公司 一种提高二氧化碳捕捉效率的煤燃烧方法
CN105351960A (zh) * 2015-11-09 2016-02-24 广西桂晟新能源科技有限公司 一种提高二氧化碳捕捉效率的贫氧燃烧方法
CN107270288A (zh) * 2017-08-07 2017-10-20 段秀春 共模同步型工业烟气复燃循环处理模块、装置及方法
CN109519917A (zh) * 2019-01-03 2019-03-26 上海华之邦科技股份有限公司 一种烟气内循环的低氮燃烧装置
WO2020136334A1 (fr) * 2018-12-28 2020-07-02 Fives Pillard Brûleur a flamme ajustable
CN113101484A (zh) * 2021-04-08 2021-07-13 江西省人民医院 一种麻醉科用免注射麻醉装置
CN113385025A (zh) * 2021-06-23 2021-09-14 苏州西热节能环保技术有限公司 一种干粉水雾三流体喷枪及使用方法
CN114877314A (zh) * 2022-05-17 2022-08-09 哈尔滨工业大学 气化粗合成气与煤耦合燃烧的旋流煤粉锅炉装置及方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4023921A (en) * 1975-11-24 1977-05-17 Electric Power Research Institute Oil burner for NOx emission control
EP0421903A2 (de) * 1989-10-04 1991-04-10 ENTREPRISE GENERALE DE CHAUFFAGE INDUSTRIEL PILLARD. Société anonyme dite: Verfahren zum Betreiben eines Brenners und Brenner für Drehofen
JPH05264015A (ja) * 1992-03-16 1993-10-12 Ishikawajima Harima Heavy Ind Co Ltd ガスタービン排気再燃用バーナ
EP0756134A1 (de) * 1995-07-25 1997-01-29 Babcock Lentjes Kraftwerkstechnik GmbH Verfahren und Brenner zur Verminderung der Bildung von NOx bei der Verbrennung von Kohlenstaub

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2518222A1 (fr) 1981-12-11 1983-06-17 Buisson Nicolas Un poele-chaudiere brule-tout
DE3706234A1 (de) 1987-02-26 1988-09-08 Sonvico Ag Ing Bureau Brenner zum verbrennen von fluessigen oder gasfoermigen brennstoffen
FR2706985B1 (de) 1993-06-22 1995-08-25 Pillard Ent Gle Chauffage Indl

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4023921A (en) * 1975-11-24 1977-05-17 Electric Power Research Institute Oil burner for NOx emission control
EP0421903A2 (de) * 1989-10-04 1991-04-10 ENTREPRISE GENERALE DE CHAUFFAGE INDUSTRIEL PILLARD. Société anonyme dite: Verfahren zum Betreiben eines Brenners und Brenner für Drehofen
JPH05264015A (ja) * 1992-03-16 1993-10-12 Ishikawajima Harima Heavy Ind Co Ltd ガスタービン排気再燃用バーナ
EP0756134A1 (de) * 1995-07-25 1997-01-29 Babcock Lentjes Kraftwerkstechnik GmbH Verfahren und Brenner zur Verminderung der Bildung von NOx bei der Verbrennung von Kohlenstaub

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 018, no. 034 (M - 1544) 19 January 1994 (1994-01-19) *

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2453223A (en) * 2007-09-28 2009-04-01 Gen Electric Gas flow injector and method of injecting gas into a combustion system
CN105299678A (zh) * 2015-11-09 2016-02-03 广西桂晟新能源科技有限公司 一种将循环水蒸气应用于煤燃烧锅炉的方法
CN105351961A (zh) * 2015-11-09 2016-02-24 广西桂晟新能源科技有限公司 一种提高二氧化碳捕捉效率的煤燃烧方法
CN105351960A (zh) * 2015-11-09 2016-02-24 广西桂晟新能源科技有限公司 一种提高二氧化碳捕捉效率的贫氧燃烧方法
CN107270288A (zh) * 2017-08-07 2017-10-20 段秀春 共模同步型工业烟气复燃循环处理模块、装置及方法
CN107270288B (zh) * 2017-08-07 2023-03-14 段秀春 共模同步型工业烟气复燃循环处理模块、装置及方法
WO2020136334A1 (fr) * 2018-12-28 2020-07-02 Fives Pillard Brûleur a flamme ajustable
FR3091331A1 (fr) * 2018-12-28 2020-07-03 Fives Pillard Brûleur a flamme ajustable
CN109519917A (zh) * 2019-01-03 2019-03-26 上海华之邦科技股份有限公司 一种烟气内循环的低氮燃烧装置
CN113101484A (zh) * 2021-04-08 2021-07-13 江西省人民医院 一种麻醉科用免注射麻醉装置
CN113385025A (zh) * 2021-06-23 2021-09-14 苏州西热节能环保技术有限公司 一种干粉水雾三流体喷枪及使用方法
CN114877314A (zh) * 2022-05-17 2022-08-09 哈尔滨工业大学 气化粗合成气与煤耦合燃烧的旋流煤粉锅炉装置及方法

Also Published As

Publication number Publication date
FR2772887B1 (fr) 2000-03-17
FR2772887A1 (fr) 1999-06-25

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