|Publication number||US3729285 A|
|Publication date||Apr 24, 1973|
|Filing date||May 22, 1972|
|Priority date||May 22, 1972|
|Also published as||CA987584A, CA987584A1|
|Publication number||US 3729285 A, US 3729285A, US-A-3729285, US3729285 A, US3729285A|
|Original Assignee||Schwedersky G|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (4), Referenced by (88), Classifications (16), Legal Events (2)|
|External Links: USPTO, USPTO Assignment, Espacenet|
' United States Patent [191 Schwedersky  3,729,285 45 Apr. '24, 1973 41 BURNER AND METHOD OF OPERATING IT TO CONTROL THE PRODUCTION OF NITROGEN OXIDES  Inventor: George H. Schwedersky, 276 Main Street, Westport, Conn. 06680  Filed: May 22, 1972  Appl. No.: 255,532
 US. Cl. ..431/8, 431/351, 431/284  Int. Cl. ..F23c 7/00  Field of Search ..431/2, 10, 187, 174,
 References Cited UNITED STATES PATENTS 3,048,131 8/1962 Hardgrave ..1 10/72 3,610,537 10/1971 Nakagawa et a1. ...239/424.5 3,308,869 3/1967 Livingston 431/187 3,163,203 12/1964 lhlenfield ..43l/284 X Primary ExaminerWilliam F. ODea Assistant Examiner-William C. Anderson Att0rneylohn W. Hoag  ABSTRACT In the operation of a burner using gaseous fuel the production of nitrogen Oxides is limited and controlled by providing successive stages of combustion and by holding down the temperature of combustion. This is accomplished by introducing the fuel in two streams of unequal volume and comprising respectively more and less than the stoichiometric percentage of air, igniting the streams in sequence, thus effecting first and second stages of combustion, and mixing and consuming the excess fuel and air of said streams respectively, thus effecting a third stage of combustion.
5 Claims, 2 Drawing Figures Patented April 24, 1973 3,729,285
lsT SIR/99M BURNER AND METHOD OF OPERATING IT TO CONTROL THE PRODUCTION OF NITROGEN OXIDES FIELD OF THE INVENTION This invention relates to a burner of the kind in which propane gas or other gaseous fuel is combined with air and burned to provide heat, as for example to provide steam in an electric power generating plant. The invention is particularly directed to the method of operating such a burner to limit and control the amount of nitrogen oxides which are produced while obtaining substantially complete and therefor efficient combustion.
SUMMARY OF THE DISCLOSURE In accordance with this invention the production of nitrogen oxides is kept at a low level by providing successive stages of combustion, each occurring at a temperature substantially less than would be obtained in a single stage of combustion using the same volumeand proportion of gaseous fuel/air. Instead of injecting gaseous fuel and air into the burner to mix and provide a single stream in which for efficient heating the percentage of air would be the optimum for obtaining complete combustion of the gaseous fuel, the gaseous fuel and air are introduced so as to form two separate streams of different volume and each comprising different ratios of gaseous fuel to air. One of the streams comprises an excess of air and theother stream comprises an excess of gaseous fuel. One of the streams is first ignited effecting a first stage of combustion. It then ignites the second stream effecting a second stage of combustion, and a third stage of combustion is provided by the mixing and burning of the excess gaseous fuel in one of the streams with the excess air in the other of the streams. The temperature created in each stage is less than would have been created if the same volumes of gas and air had been mixed and consumed in a single stage, but the total of heat produced is substantially the same as would have been produced in a single combustion stage.
The invention will be best understood if the following description is read in connection with the drawing in which:
FIG. 1 is a side elevation showing a burner having two sets of gas and air inlets disposed to provide two separate gaseous fuel/air mixture streams and means for igniting them, and the excess air from one stream and the excess gaseous fuel from the other stream, in sequence providing a cascading three stage combustion, and
FIG. 2 is a vertical section taken on the line 2-2 of FIG. 1.
DESCRIPTION Great difflculty has been experienced in attempting to reduce the amount of nitrogen oxide produced in air-gas burners. It is well established by experiments that the production of nitrogen oxides is highest when the mixture of gaseous fuel and air employed is close to the optimum mixture for combustion, or, in other words close to the point where the temperature of combustion is the highest. Reference to the Proceedings, Conference on Natural Gas Research and Technology,
sponsored by American Gas Association, Inc. and Institute of Gas Technology, held at Chicago, Ill., Feb. 28Mar. 3, 1971, and particularly to Session IV, Paper 2, and the curve which is shown on page 20 of that Paper and is identified as FIG. 7., Variation of Nitrogen Oxides Concentration with Stoichiometry for a Premixed Natural Gas/Air Flame consuming 200 Standard Cubic Feet Per Hour of Gas, indicates that the maximum production of nitrogen oxide occurs when a percent of air slightly in excess of the optimum amount of air for combustion, about 107 percent of stoichiometric air, is mixed with the gaseous fuel, and that the production of nitrogen oxides falls off rapidly when the percentage of stoichiometric air by volume is further increased, or is decreased. The curve indicates that when the gas/air mixture burned comprises approximately l07 percent of stoichiometric air by volume the accompanying production of nitrogen oxides is 120 parts per million by volume, dry basis, whereas when 140 percent of stoichiometric air is employed the nitrogen oxides concentration falls to approximately parts per million by volume. Similarly the curve indicates that if only percent of stoichiometric air by volume is present in the gas/air mixture production of nitrogen oxides falls to approximately 70 parts per million by volume.
In order to reduce the temperature at the time of ignition and thereby substantially reduce the production of nitrogen oxides I have employed the information indicated by the said curve to limit and control the production of nitrogen oxides and at the same time obtain an efficient and substantially complete combustion. In order to accomplish this, instead of introducing into the burner a single mixture of gas and air, in accordance with my method two mixtures of gaseous fuel and air are introduced separately into the burner and ignited in sequence. One of the gaseous fuel-air mixtures comprises substantially more than percent of stoichiometric air and the other gaseous fuel-air mixture comprises substantially less than 100 percent of stoichiometric air. The first mentioned mixture therefor comprises a substantial excess of air and the second gaseous fuel-air mixture comprises a substantial excess of gaseous fuel. When the two streams are ignited the temperature produced by each will be substantially less than the temperature produced by igniting a single gaseous fuel-air stream having the volume of the combined two streams, and comprising 100 percent of stoichiometric air. The temperature close to the burner face is therefor greatly reduced, the exact amount of reduction varying to some extent depending upon the gaseous fuel employed.
With a single stream of gaseous fuel/air, if the ratio is the optimum for obtaining complete combustion, the high flame temperature realized at the burner will fall off gradually as the gases travel to the flue. In the case of the two streams which are ignited in succession and comprise the same total volume of gaseous fuel/air as a single stream, the flame temperature initially adjacent the burner face is lower because of the excess air and excess fuel in the two streams, but the temperature of the gases is sustained by the combustion in the second and third stages, and that temperature will be substantially the same as that of the single stream' when the gases of the two streams reach the furnace flue and therefor the total transfer of heat is essentiallythe same. h j
By properly proportioning' the volume of the two gaseous fuel/air mixtures and the ratio..of gaseous fuel to air in each mixture the excess of air in one of the mixtures can be'proportioned to the amount of excess fuel in the other of the mixtures so that during the three stages of combustion complete or substantially complete combustion will be realized and a total production of heat obtained equal to, or substantially equal to the amount of heat which can be obtained from a single stream of gaseous fuel equal in volume to the gaseous fuel in the two streams and mixed with lOO percent of stoichiometric air, the essential difference being that by the single flame a flash temperature approximating 2,800 F. 3,200 F. would be obtained whereas by employing three stages of combustion as described above a much lower temperature near the burner face is obtained, a temperature which in the case of natural gas would be in the neighborhood of 2,l F. 2,400 F. Reference to FIG. 8 on page 21 of Paper 2, Session IV of the aforesaid Proceedings of the Conference on Natural Gas Research and Technology shows that close to the burner face a higher temperature results in a proportionately greater concentration of nitrogen oxides measured in parts per million by volume on a dry basis.
In the embodiment illustrated in the drawings a burner 10 comprises a burner face 12 disposed between air and gaseous fuel supply conduits l4, l6 and 18, and a burner tile chamber 22 which at its far end opens into the combustion chamber 24 of a furnace or the like indicated generally by the numeral 26. As shown the burner tile chamber 22 projects into the furnace combustion chamber 24 and a wall 28 of the furnace extends around the burner tile chamber.
Gaseous fuel conduit 14 and the surrounding air conduit l6 communicate with the interior of the burner tile chamber 22 through orifices and 32 respectively in the burner face 12. Gas and air is supplied under pressure through said conduits to mix adjacent the burner face and provide a first gaseous fuel/air stream. This stream is ignited by a suitable ignition means 36, preferably disposed at the burner face, and it may have the ignition wire 36a extending to it through conduit 14, and the flame is directed into the tubular and perforate choke collar 34.
Gaseous fuel conduit 18 and the air conduit 20 communicate with the interior of the burner tile chamber through the orifices and 42. Gas and air is supplied through conduits 18 and 20 respectively to mix and form a second gaseous fuel/air stream which is concentric with, and spaced radially outwardly of, the first stream. The second stream is not directed into the choke collar 34 but flows around it, and is ignited after the first stream by the flame of the first stream issuing through the perforations 35 in the choke collar 34. The excess of fuel in one stream mixes with the excess air in the other stream and is ignited within the merged flame 44 resulting from the sequential ignition of the'two streams thus providing a third stage ofignition.
It will be noted that wall 46 separates the two sets of conduits which supply the two streams,.and that orifices 40 are inclined to direct the gaseous fuel from conduit 18 to mix with air from conduit 20 and not to be injected into thechokelcollar 34. The burner tile is shaped so as to bring'the excess fuel into the center stream thus mixing it with the excess air causing them to burn and thus releaseall. of the heat from the fuel supplied in the two streams.
It will be understood that if desired the two streams of gaseous fuel/airmay be premixed before entering the burner.
The conduits 14 and 16 may be employed to provide a constant minimum supply of gaseous fuel and the conduits 18 and 20 may be controlled to increase the fuel supply as may be desired.
To illustrate my method more specifically I prefer to use two mixed streams of gaseous fuel/air which differ in volume by the ratio of one to three, with a 1 to 1.75 proportion of gas to stoichiometric air in the smaller stream, and a l to 0.75 proportion of gas to stoichiometric air in the larger stream. This means that in the smaller stream there will be percent excess air, and in the larger stream there will be a 25 percent deficiency of air, or stated oppositely a 25 percent excess of gas. When these two streams are ignited in sequence all of the gas in the smaller stream will be ignited and burned close to the burner leaving approximately 75 percent unconsumed air which will flow outwardly within the burner tile chamber and the combustion chamber. All of the air in the second stream will combine with gas in the second stream and will be ignited and burned a little further from the burner face, leaving an excess of 25 percent of gas which will flow outwardly within the burner tile chamber and the combustion chamber and become mixed with the excess air from the first stream. Since the volume of the larger stream is three times as great as that of the first stream there will be relative volumes of gaseous fuel and air which are the optimum for complete combustion and this mixture will burn in a third stage of combustion which is a continuation of the first and second stages, the three stages occurring at progressively greater distances from the burner face. Thus in successive stages complete or substantially complete combv ation of the total amount of gaseous fuel and air will be achieved, but the temperature of each stage will be very substantially less than in the case of a single stage of combustion employing percent stoichiometric air and the same total volume of gaseous fuel, and the total amount of heat produced will be the same or approximately the same as would have been obtained from a single stage of combustion at a much higher initial temperature.
LIST OF PARTS l0 burner 12 burner face 14 gaseous fuel conduit 16 air conduit 18 gaseous fuel conduit 20 air conduit 22 burner tile chamber 24 combustion chamber 26 furnace 28 wall of 26 30 orifice for conduit 14 32 orifices forfc 'onduit 16 34 choke collar 35 perforations in 34 36 ignition means 36a ignition wire 40 orifices for conduit 18 42 orifices for conduit 44 merged flame 46 wall of burner What I claim is:
1. In the operation ofa burner the steps of,
introducing into the burner two streams of mixed air and fuel in gaseous phase,
controlling the air to fuel ratio of the streams so that one comprises an excess of stoichiometric air and the other comprises an excess of fuel and,
igniting said streams in sequence, and thereafter mixing the excess air from one stream with the excess fuel from the other stream and burning the resulting mixture.
2. The method claimed in claim 1 in which one of said streams is of greater volume than the other, and the sum of the percentages'of air in the two streams approximates the optimum or stoichiometric air percentage.
3. A burner adapted to provide combustion of gaseous fuel and air in successive stages which comprises:
gaseous fuel and air conduits,
a burner tile chamber,
a perforate choke collar within the burner tile chamber,
an ignition means disposed at the burner face,
conduit and orifice meanS for injecting a first stream of mixed gaseous fuel and air into the choke collar within the burner tile chamber, and other conduit and orifice means for injecting a second stream of mixed gaseous fuel and air into the burner tile chamber to pass over and around the choke collar.
4. The burner claimed in claim 3 in which the said conduits are concentric and the choke collar is axially aligned with the center conduit means.
5. In the operation of a burner using a gaseous fuel/air mixture which when burned forms nitrogen oxides, the concentration of the nitrogen oxides being greatest when the volume of air employed is substantially the optimum for combustion and therefor when burned has a high temperature, the step of minimizing the temperature of combustion and the formation of the nitrogen oxides by providing multistage combustion at successive distances from the burner face said multistage combustion being achieved by dividing the gaseous fuel/air supply into two streams, one of the streams comprising excess air and the other stream comprising excess gaseous fuel, igniting the said two streams in successive stages and thereafter mixing and burning the remaining excess air and excess fuel from said streams respectively providing a third stage of combustion.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3048131 *||Jun 18, 1959||Aug 7, 1962||Babcock & Wilcox Co||Method for burning fuel|
|US3163203 *||Dec 6, 1961||Dec 29, 1964||Brown Fintube Co||Liquid and gaseous fuel burner|
|US3308869 *||Dec 17, 1965||Mar 14, 1967||Combustion Eng||Liquid fuel burner for wide range of load|
|US3610537 *||Jan 27, 1969||Oct 5, 1971||Daido Oxygen||Liquid fuel combustion device|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3822654 *||Jan 8, 1973||Jul 9, 1974||Ghelfi S||Burner for burning various liquid and gaseous combustibles or fuels|
|US3890084 *||Sep 26, 1973||Jun 17, 1975||Coen Co||Method for reducing burner exhaust emissions|
|US3907488 *||Feb 14, 1974||Sep 23, 1975||Mitsubishi Heavy Ind Ltd||Method of burning fuels by means of a burner|
|US3914090 *||Oct 8, 1974||Oct 21, 1975||Engelhard Min & Chem||Method and furnace apparatus|
|US3918834 *||Aug 9, 1973||Nov 11, 1975||Nikolai Alexandrovich Gurevich||Method of reducing the concentration of nitrogen oxides in a gaseous effluent from a thermal plant|
|US3976420 *||Mar 3, 1975||Aug 24, 1976||Mitsubishi Jukogyo Kabushiki Kaisha||Method and apparatus for burning fuels|
|US4018554 *||Jan 14, 1976||Apr 19, 1977||Institutul Pentru Creatie Stintifica Si Tehnica-Increst||Method of and apparatus for the combustion of liquid fuels|
|US4021191 *||Mar 5, 1975||May 3, 1977||Aqua-Chem, Inc.||Reduction of pollutants in gaseous hydrocarbon combustion products|
|US4062182 *||Dec 15, 1975||Dec 13, 1977||Mtu Motoren-Und Turbinen-Union Gmbh||Combustion chamber for gas turbine engines|
|US4095928 *||Feb 14, 1977||Jun 20, 1978||Southern California Edison Company||Method of reducing nitrogen oxide emissions in flue gas|
|US4095929 *||Mar 14, 1977||Jun 20, 1978||Combustion Engineering, Inc.||Low BTU gas horizontal burner|
|US4098255 *||Sep 7, 1976||Jul 4, 1978||Thermo Electron Corporation||Dual fuel radiant tube burner|
|US4117075 *||Aug 7, 1974||Sep 26, 1978||Agency Of Industrial Science & Technology||Method of combustion for depressing nitrogen oxide discharge|
|US4157889 *||Apr 13, 1977||Jun 12, 1979||Societe Colmant Cuvelier||Burner for powdered fuel|
|US4204402 *||Sep 8, 1977||May 27, 1980||The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration||Reduction of nitric oxide emissions from a combustor|
|US4257760 *||Jan 4, 1979||Mar 24, 1981||Schuurman Hubert G||Cyclone burners|
|US4260367 *||Dec 11, 1978||Apr 7, 1981||United Technologies Corporation||Fuel nozzle for burner construction|
|US4285193 *||Oct 24, 1978||Aug 25, 1981||Exxon Research & Engineering Co.||Minimizing NOx production in operation of gas turbine combustors|
|US4292274 *||Aug 4, 1980||Sep 29, 1981||United Technologies Corporation||Catalytic reactor with improved burner|
|US4395223 *||Dec 31, 1980||Jul 26, 1983||Hitachi Shipbuilding & Engineering Co., Ltd.||Multi-stage combustion method for inhibiting formation of nitrogen oxides|
|US4494923 *||Aug 15, 1983||Jan 22, 1985||L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude||Oxy-fuel burners|
|US4496306 *||Apr 18, 1984||Jan 29, 1985||Hitachi Shipbuilding & Engineering Co., Ltd.||Multi-stage combustion method for inhibiting formation of nitrogen oxides|
|US4544350 *||Oct 27, 1982||Oct 1, 1985||Vista Chemical Company||Burner apparatus for simultaneously incinerating liquid, dry gas and wet gas streams|
|US4622007 *||Aug 17, 1984||Nov 11, 1986||American Combustion, Inc.||Variable heat generating method and apparatus|
|US4644879 *||Nov 22, 1985||Feb 24, 1987||L. & C. Steinmuller Gmbh||Method and annular burner for spraying aqueous additive suspension in the central portion of an annular burner|
|US4776320 *||Sep 12, 1986||Oct 11, 1988||Carrier Corporation||Device for inhibiting NOx formation by a combustion system|
|US4797087 *||Jul 9, 1986||Jan 10, 1989||American Combustion, Inc.||Method and apparatus for generating highly luminous flame|
|US4810189 *||Feb 10, 1987||Mar 7, 1989||Furukawa Electric Co., Ltd.||Torch for fabricating optical fiber preform|
|US4874310 *||Feb 25, 1988||Oct 17, 1989||Selas Corporation Of America||Low NOX burner|
|US5263849 *||Dec 20, 1991||Nov 23, 1993||Hauck Manufacturing Company||High velocity burner, system and method|
|US5277578 *||Dec 8, 1992||Jan 11, 1994||Gaz Metropolitain & Co., Ltd. And Ptnr.||Gas burner having tangential counter-rotation air injectors and axial gas injector tube|
|US5340305 *||May 28, 1992||Aug 23, 1994||Joyce John V||Low NOx gas burner|
|US5599375 *||Nov 10, 1994||Feb 4, 1997||American Combustion, Inc.||Method for electric steelmaking|
|US5714113 *||Aug 29, 1995||Feb 3, 1998||American Combustion, Inc.||Apparatus for electric steelmaking|
|US5788921 *||Oct 29, 1996||Aug 4, 1998||American Combustion, Inc.||Apparatus for electric steelmaking|
|US5843368 *||Apr 22, 1997||Dec 1, 1998||American Combustion, Inc.||Apparatus for electric steelmaking|
|US5858302 *||Nov 6, 1996||Jan 12, 1999||American Combustion, Inc.||Apparatus for electric steelmaking|
|US5904895 *||Apr 16, 1998||May 18, 1999||American Combustion, Inc.||Apparatus for electric steelmaking|
|US5954855 *||Apr 22, 1997||Sep 21, 1999||American Combustion, Inc.||Method for electric steelmaking|
|US6206686||May 1, 1998||Mar 27, 2001||North American Manufacturing Company||Integral low NOx injection burner|
|US6409499 *||Aug 24, 1999||Jun 25, 2002||The Boc Group Plc||Variable stoichiometric combustion|
|US6481998||Jun 7, 1995||Nov 19, 2002||Ge Energy And Environmental Research Corporation||High velocity reburn fuel injector|
|US6652265||Dec 5, 2001||Nov 25, 2003||North American Manufacturing Company||Burner apparatus and method|
|US6802178||Sep 12, 2002||Oct 12, 2004||The Boeing Company||Fluid injection and injection method|
|US6857274||Mar 26, 2004||Feb 22, 2005||The Boeing Company||Fluid injector and injection method|
|US6896509 *||Jan 14, 2004||May 24, 2005||Alstom Technology Ltd||Combustion method and burner for carrying out the method|
|US6929469||Feb 26, 2003||Aug 16, 2005||North American Manufacturing Company||Burner apparatus|
|US7163392||Sep 3, 2004||Jan 16, 2007||Feese James J||Three stage low NOx burner and method|
|US7717701 *||Oct 24, 2006||May 18, 2010||Air Products And Chemicals, Inc.||Pulverized solid fuel burner|
|US7775791 *||Feb 25, 2008||Aug 17, 2010||General Electric Company||Method and apparatus for staged combustion of air and fuel|
|US8062027||Aug 9, 2006||Nov 22, 2011||Elster Gmbh||Industrial burner and method for operating an industrial burner|
|US8696349 *||Dec 3, 2004||Apr 15, 2014||L'Air Liquide, Société Anonyme pour l'Étude et l'Éxploitation des Procédés Georges Claude||Staged combustion method using a low-oxygen gas|
|US8911230||Nov 23, 2009||Dec 16, 2014||WS Waermeprozesstechnik, GmbH||Assisted flameless oxidation operation and burner therefor|
|US20020127504 *||Oct 29, 2001||Sep 12, 2002||Neville Thomas B.||Premix burner with firing rate control|
|US20040050070 *||Sep 12, 2002||Mar 18, 2004||The Boeing Company||Fluid injector and injection method|
|US20040146820 *||Jan 14, 2004||Jul 29, 2004||Richard Carroni||Combustion method and burner for carrying out the method|
|US20040177619 *||Mar 26, 2004||Sep 16, 2004||The Boeing Company||Fluid injector and injection method|
|US20050016218 *||Jul 7, 2004||Jan 27, 2005||Tomohiro Ishihara||Method of producing glass-particle-deposited body and glass-particle-synthesizing burner|
|US20050053877 *||Sep 3, 2004||Mar 10, 2005||Hauck Manufacturing Company||Three stage low NOx burner and method|
|US20050074711 *||Feb 26, 2003||Apr 7, 2005||Cain Bruce E.||Burner apparatus|
|US20070037107 *||Aug 9, 2006||Feb 15, 2007||Lbe Feuerungstechnik Gmbh||Industrial burner and method for operating an industrial burner|
|US20070281254 *||Dec 3, 2004||Dec 6, 2007||Bertrand Leroux||Staged Combustion Method Using A Low-Oxygen Gas|
|US20080184919 *||Oct 24, 2006||Aug 7, 2008||D Agostini Mark Daniel||Pulverized solid fuel burner|
|US20090214989 *||Feb 25, 2008||Aug 27, 2009||Larry William Swanson||Method and apparatus for staged combustion of air and fuel|
|US20090291401 *||Aug 7, 2007||Nov 26, 2009||Mitsubishi Heavy Industries, Ltd.||Burner|
|US20100119984 *||Nov 6, 2009||May 13, 2010||Fox Allen G||Abatement system|
|US20120255472 *||Jun 10, 2011||Oct 11, 2012||Gordon Norman R||Burner assembly and method for reducing nox emissions|
|US20130122436 *||Nov 11, 2011||May 16, 2013||General Electric Company||Combustor and method for supplying fuel to a combustor|
|USRE33464 *||Feb 3, 1989||Nov 27, 1990||American Combustion, Inc.||Method and apparatus for flame generation and utilization of the combustion products for heating, melting and refining|
|CN101063524B||Apr 26, 2007||Apr 20, 2011||气体产品与化学公司||Ultra-low Nox burner assembly|
|CN101715529B||May 6, 2008||Jan 2, 2013||Ws-热处理技术有限责任公司||Supported fLOX operation and burner thereof|
|CN102679338A *||May 30, 2012||Sep 19, 2012||山西蓝天环保设备有限公司||Efficient coal dust combustor for reducing smoke NOx content|
|CN102679338B||May 30, 2012||Jul 23, 2014||山西蓝天环保设备有限公司||Efficient coal dust combustor for reducing smoke NOx content|
|DE2510126A1 *||Mar 5, 1975||Sep 18, 1975||Mitsubishi Heavy Ind Ltd||Verfahren und vorrichtung zum verbrennen von fluessigen und gasfoermigen brennstoffen|
|DE4336095A1 *||Oct 22, 1993||Apr 27, 1995||Abb Research Ltd||Combustion method for atmospheric firings and device for carrying out the method|
|EP0291111A1 *||Apr 27, 1988||Nov 17, 1988||Shell Internationale Research Maatschappij B.V.||Process for partial oxidation of a hydrocarbon-containing gaseous fuel|
|EP0562816A2 *||Mar 23, 1993||Sep 29, 1993||The Boc Group, Inc.||Method for combustion of a fuel|
|EP0562816A3 *||Mar 23, 1993||Feb 2, 1994||Boc Group Inc||Title not available|
|EP0866139A1 *||Mar 16, 1998||Sep 23, 1998||Praxair Technology, Inc.||Lance/burner for molten metal furnace|
|EP1398566A2 *||Sep 5, 2003||Mar 17, 2004||The Boeing Company||Fluid injector and injection method|
|EP1398566A3 *||Sep 5, 2003||Mar 31, 2004||The Boeing Company||Fluid injector and injection method|
|EP1995515A1||May 23, 2007||Nov 26, 2008||WS-Wärmeprozesstechnik GmbH||Supported FLOX operation and burner therefor|
|WO1990002907A1 *||Sep 2, 1988||Mar 22, 1990||American Combustion, Inc.||Method and apparatus for generating highly luminous flame|
|WO1999057489A1 *||Apr 29, 1999||Nov 11, 1999||North American Manufacturing Company||INTEGRAL LOW NOx INJECTION BURNER|
|WO2007045807A1 *||Oct 20, 2006||Apr 26, 2007||Lafarge||Burner for a clinker furnace|
|WO2008141722A1 *||May 6, 2008||Nov 27, 2008||Ws-Wärmeprozesstechnik Gmbh||Supported flox operation and burner therefor|
|WO2016102825A1||Dec 17, 2015||Jun 30, 2016||L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude||Oxy-fuel burner for low-calorific fuel gas and use thereof|
|WO2016180623A1 *||Apr 25, 2016||Nov 17, 2016||Outotec (Finland) Oy||Low nox combustion system for travelling grate pelletizing plants|
|U.S. Classification||431/8, 431/284, 431/351|
|International Classification||F23D14/00, F23C6/04, C21C5/52, C21C5/00, F23C6/00, F23D14/22|
|Cooperative Classification||F23D14/22, F23C6/047, C21C5/5217, F23C2201/20|
|European Classification||F23C6/04B1, F23D14/22, C21C5/52B2|
|Feb 27, 1985||AS02||Assignment of assignor's interest|
Owner name: SCHWEDERSKY, MABEL ELIZABETH, WESTPORT, CT
Owner name: SCWEDERSKY, MABEL E., EXECUSTRIX OF THE ESTATE OF
Effective date: 19850108
|Feb 27, 1985||AS||Assignment|
Owner name: SCHWEDERSKY, MABEL ELIZABETH, WESTPORT, CT
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:SCWEDERSKY, MABEL E., EXECUSTRIX OF THE ESTATE OF EROGE H. SCHWEDERSKY, DECEASED.;REEL/FRAME:004370/0155
Effective date: 19850108