Having Secondary Air Mixing Means Patents (Class 110/265)
  • Publication number: 20120247376
    Abstract: A combustion burner 1 includes a fuel nozzle 2 that injects fuel gas prepared by mixing solid fuel and primary air, secondary air nozzles 3, 4 that inject secondary air from the outer periphery of the fuel nozzle 2, and a flame holder 5 that is arranged in an opening of the fuel nozzle 2. In the combustion burner 1, the flame holder 5 has a splitting shape that widens in the flow direction of the fuel gas. When seen in cross section along a direction in which the flame holder 5 widens, the cross section passing through the central axis of the fuel nozzle 2, a maximum distance h from the central axis of the fuel nozzle 2 to the widened end of the flame holder 5 and an inside diameter r of the opening 21 of the fuel nozzle 2 satisfy h/(r/2)<0.6.
    Type: Application
    Filed: March 11, 2010
    Publication date: October 4, 2012
    Applicant: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Keigo Matsumoto, Koutaro Fujimura, Kazuhiro Domoto, Toshimitsu Ichinose, Naofumi Abe, Jun Kasai
  • Publication number: 20120251959
    Abstract: A method of feeding at least one of light, fine and moist fuel into a furnace of a circulating fluidized bed boiler. Fuel is fed into the furnace through a fuel feed and the fuel is combusted in a turbulent, circulating fluidized bed. A fuel feed area is isolated from the turbulent circulating bed by arranging the fuel feed along at least one channel arranged in a wall of the furnace. Solids of the circulating bed material are introduced onto a first grid section at the bottom of the fuel feed area. The fuel and the solids are mixed and fluidized above the grid section to form a fuel-solids mixture that flows laterally onto a second grid section and a third grid section where the mixture is fluidized. The fluidized bed material is circulated both inside and outside of the furnace. The bed material is separated from the flue gases and returned to the furnace.
    Type: Application
    Filed: October 29, 2010
    Publication date: October 4, 2012
    Applicant: FOSTER WHEELER ENERGIA OY
    Inventors: Marcin Klajny, Pertti Kinnunen
  • Publication number: 20120237883
    Abstract: A method of feeding at least one of light, fine, volatile and moist fuel into a furnace of a circulating fluidized bed boiler. Fuel is introduced into the furnace and is combusted in the presence of a fluidized bed material to form flue gases. The fluidized bed material is circulated both inside the furnace in an internal circulation in which bed material returns along walls of the furnace down to the bottom of the furnace, and outside the furnace in an external circulation that includes at least a solids separator arranged in flow communication with the furnace. Bed material is separated from the flue gases in the separator. The flue gases are removed from the separator for further treatment. The separated bed material is returned to the furnace.
    Type: Application
    Filed: October 29, 2010
    Publication date: September 20, 2012
    Applicant: FOSTER WHEELER ENERGIA OY
    Inventors: Marcin Klajny, Kari Kauppinen, Pertti Kinnunen, Jouni Miettinen, Kari Myöhänen, Pekka Lehtonen
  • Publication number: 20120210917
    Abstract: Burner for conveyor gas propelled particulate solid fuel, said burner comprising a burner block and an injector assembly, the injector assembly being at least partially surrounded by an injector passage of the burner block, the injector assembly comprising an inner oxygen supply pipe surrounding a fuel injector, which in turn surrounds an oxygen injector, each having a downstream end on the side of the passage outlet, the inner oxygen supply pipe having a lateral surface onto which are mounted a set of lateral primary oxygen nozzles for the injection of lateral jets of primary oxygen into the fuel injector with an injection orientation which follows a same sense of rotation around the longitudinal direction and which is directed towards the downstream end of the fuel injector, said lateral primary oxygen nozzles being positioned at a number of different distances from the downstream end of the fuel injector.
    Type: Application
    Filed: October 29, 2010
    Publication date: August 23, 2012
    Inventors: Brenice Belasse, Jacques Mulon, Faustine Panier, Xavier Paubel, Remi Tsiava
  • Publication number: 20120174837
    Abstract: A combustor assembly in a coal burning power plant includes a combustor housing that defines a combustion zone in which pulverized coal is burned, at least one burner that introduces pulverized coal into the combustion zone, and an overfire air port that injects air into the combustor housing above the combustion zone, the overfire air port being generally not movable with respect to the combustor housing. The combustor assembly further includes a nozzle assembly associated with the overfire air port. The nozzle assembly includes a flow directing structure disposed within the overfire air port, which flow directing structure is tiltable with respect to the overfire air port to effect a change in a flow direction of the air being injected into the combustor housing through the overfire air port.
    Type: Application
    Filed: October 20, 2011
    Publication date: July 12, 2012
    Inventors: JIEFENG SHAN, Sergey Kaushansky
  • Patent number: 8196531
    Abstract: Disclosed is a burner for oxidant gasification of pulverized fuels under high pressures, e.g. 80 bar, and temperatures, e.g. 1200 to 1900° C., in reactors with liquid slag removal for oxygen gasification. The individual pulverized coal supply tubes in the burner are inclined toward the burner axis in the direction of the burner mouth, are implemented equiareally from the burner inlet up to the burner outlet, and end at the burner mouth adjacent to the oxidant outlet. Owing to the pulverized fuel feeding elements being implemented right up to the burner mouth and the instantaneous entry of the pulverized coal into the rotating oxygen stream there is no longer any areal discontinuity at the dust outlet, since here the pulverized coal stream is immediately sucked into the oxidant stream. At the outlet of the media the individual pulverized coal streams merge into a single rotating pulverized coal/oxygen stream, thereby achieving an even flame spread and stabilization.
    Type: Grant
    Filed: May 6, 2008
    Date of Patent: June 12, 2012
    Assignee: Siemens Aktiengesellschaft
    Inventors: Dietmar Degenkolb, Christian Reuther, Manfred Schingnitz
  • Publication number: 20120137938
    Abstract: A pulverized coal boiler of the present invention is structured so as to form, among upper and lower after-air nozzles, an opening serving as an outlet of the lower after-air nozzle positioned on the upstream side is formed in a rectangular shape, a cylindrical section for defining a minimum flow path area of combustion air flowing through a flow path of the after-air nozzle is installed inside of the lower after-air nozzles along the flow path of the lower after-air nozzle, and a swirl blade for giving a swirl force to the combustion air flowing through the flow path of the after-air nozzles is installed inside of the cylindrical section, and the flow path of the lower after-air nozzles is formed so that a flow path area of the flow path of the after-air nozzles through which the combustion air flows from a position where the cylindrical section is installed toward the opening of each of the lower after-air nozzles is expanded.
    Type: Application
    Filed: August 3, 2010
    Publication date: June 7, 2012
    Inventors: Akihito Orii, Hirofumi Okazaki, Yusuke Ochi
  • Patent number: 8176911
    Abstract: A method to regulate overfire air passing through an overfire air duct and entering a flue gas stream in a combustion system including: directing overfire air into an inlet of the overfire air duct, passing the overfire air through the duct and discharging the overfire air into the flue gas stream in the combustion system; adjusting a flow rate of overfire air entering the inlet using a damper adjacent the inlet, and moving the damper parallel along an axis of the overfire air duct to increase and decrease the overfire air entering the inlet, wherein the damper has an open position at which the damper is extended out of the inlet and a closed position in which the damper is substantially in the inlet and blocking air entering the inlet.
    Type: Grant
    Filed: February 23, 2010
    Date of Patent: May 15, 2012
    Assignee: General Electric Company
    Inventors: Robert W. Waltz, Quang H. Nguyen
  • Publication number: 20110203498
    Abstract: A process that uses targeted in-furnace Injection to feed a fluxing agent of the chemical family of compositions containing boron and/or alkali hydrates to either decrease heat transfer on waterwalls of utility furnaces burning solid fuels to improve steam generation, maintain steam temperature, and/or allow a protective layer of slag to form inside the barrels of cyclones on cyclone boilers burning fuels high in calcium so that the boiler can operate at a wider variety of power settings while allowing proper flow and drainage of slag from the cyclone barrels.
    Type: Application
    Filed: February 23, 2011
    Publication date: August 25, 2011
    Applicant: Fuel Tech Inc.
    Inventors: Christopher R. Smyrniotis, Kent W. Schulz
  • Patent number: 7926432
    Abstract: A low NOx Cyclone furnace steam generator including redesigned or modified Cyclone furnaces, air flow distribution, and new or relocated air ports maintains and/or minimizes NOx emission levels from the Cyclone furnace steam generator while minimizing Cyclone furnace and steam generator furnace tube wastage.
    Type: Grant
    Filed: February 6, 2006
    Date of Patent: April 19, 2011
    Inventors: Gerald J. Maringo, George H. Harth, III, Manvil O. Dahl, Linda P. Dahl, legal representative, Steven W. Burge, Rosemary Burge, legal representative, Mitchell W. Hopkins
  • Publication number: 20110073020
    Abstract: An oxyfuel combustion boiler plant comprising: an air separation unit for manufacturing oxygen by separating nitrogen from air, a boiler having a burner for burning the oxygen supplied from the air separation unit and pulverized coal, and a primary system pipe for supplying the pulverized coal to the burner, an exhaust gas recirculation system pipe for supplying combustion exhaust gas discharged from the boiler to the primary system pipe, and a carbon dioxide capture unit for capturing carbon dioxide in the exhaust gas discharged from the boiler, the oxyfuel combustion boiler plant is further comprising: an oxygen supply pipe for supplying the oxygen manufactured by the air separation unit to the primary system pipe in the burner, and a pipe for supplying the combustion exhaust gas discharged from the boiler to the oxygen supply pipe, wherein an injection port of the oxygen supply pipe is disposed on an upstream side of an injection portion of the burner.
    Type: Application
    Filed: September 29, 2010
    Publication date: March 31, 2011
    Applicant: Hitachi, Ltd.
    Inventors: Masayuki TANIGUCHI, Tsuyoshi Shibata, Yoshiharu Hayashi
  • Patent number: 7913632
    Abstract: A method of combustion for pulverized hydrocarbonaceous fuel includes injecting a concentrated fuel and air stream into a burner, causing a low-pressure zone; directing a flow of a high-temperature combustion gas from a combustion chamber into the low-pressure zone in the burner; mixing the high-temperature combustion gas with the injected concentrated stream to heat the injected concentrated stream; injecting the heated concentrated stream from the burner to the combustion chamber, wherein the concentrated stream is rapidly devolatilized and combusted in a flame that has a fuel-rich flame zone; sensing a combustion parameter; and, based on the sensed combustion parameter, controlling combustion to achieve at least one of a desired NOx reduction and a desired distance from the burner to a flame front.
    Type: Grant
    Filed: November 22, 2005
    Date of Patent: March 29, 2011
    Assignee: Clean Combustion Technologies LLC
    Inventors: Zhen Jia, Taofang Zeng, Xiaoguang Jia, Xing Li
  • Publication number: 20110048293
    Abstract: In a boiler furnace having nozzles for introducing combustion media such as air and coal, nozzle tip walls that have the greatest exposure to radiant heat and hot gases are provided with arrays of air holes that allow air to flow to the exposed sides of the walls from the opposite sides in order to reduce the temperature difference between the two sides and thereby reduce thermal distortion and damage resulting from oxidation.
    Type: Application
    Filed: August 26, 2009
    Publication date: March 3, 2011
    Applicant: R-V INDUSTRIES, INC.
    Inventor: John Grusha
  • Patent number: 7896645
    Abstract: A system when installed in-line with a pollution source provides reduction and/or complete combustion of harmful emissions generated there from. Such emissions including (but not limited to) compounds such as oxides of nitrogen, hydrocarbons, carbon monoxide, odors, organic and inorganic particulates. The pollution source can be of any type, such as smoke from a smokestack, engine exhaust, etc. The re-burner system is of very simple construction, is extremely energy efficient and does not require any moving parts or maintenance, respectively.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: March 1, 2011
    Assignee: Universal Cleanair Technologies
    Inventor: Ronald Everett Loving
  • Patent number: 7832341
    Abstract: A method of injection and combustion control and related injection nozzles and lances are described which facilitate the merging of the combustion of fossil fuels and separately added solid biomass waste product fuels in the form of pelletized chars and fine particulates. An assembly of five concentric, annular tubes and conically shaped exit tips is used to deliver air conveyed biomass fuel as an annular stream between two higher velocity air streams, both of which converge so as to accelerate and propel the biomass fuel, and distribute it into the flame zone produced in a conventional fossil fueled boiler. The additional air required for combustion of the biomass fuel is fed to the expanding plume produced by the fuel delivery stream and adjoining air streams. A portion of the combustion air is delivered through the inside of the inner tube in sufficient volume to provide the entrainment flow produced by the expanding air streams.
    Type: Grant
    Filed: April 22, 2009
    Date of Patent: November 16, 2010
    Inventor: William Arthur Walsh, Jr.
  • Publication number: 20100269741
    Abstract: A solid fuel burner and its combustion method suited for encouraging fuel ignition and avoiding slugging caused by combustion ash, wherein a gas of low oxygen concentration (exhaust combustion gas) is used as a carrier gas of such a low grade solid fuel as brown coal. An additional air nozzle for jetting additional air having a velocity component in the circumferential direction of a fuel nozzle is provided in the fuel nozzle, thereby encouraging mixing between the fuel and air in the fuel nozzle. Further, the amount of air supplied from the additional air nozzle is adjusted in response to the difference in combustion loads. Under light load, the amount of air supplied from the additional air nozzle is increased so as to increase the oxygen concentration of the circulating flow formed downstream of the outside of the outlet of the fuel nozzle, whereby stable combustion is ensured.
    Type: Application
    Filed: July 2, 2010
    Publication date: October 28, 2010
    Applicant: BABCOCK-HITACHI K.K.
    Inventors: Hirofumi OKAZAKI, Kenji YAMAMOTO, Kenji KIYAMA, Kouji KURAMASHI
  • Patent number: 7775791
    Abstract: A method for operating a fuel-fired furnace including at least one burner is provided. The method includes channeling a first fluid flow to the at least one burner at a first predetermined velocity, and channeling a second fluid flow to the at least one burner at a second predetermined velocity during a first mode of operation of the at least one burner. The second predetermined velocity is different than the first predetermined velocity.
    Type: Grant
    Filed: February 25, 2008
    Date of Patent: August 17, 2010
    Assignee: General Electric Company
    Inventors: Larry William Swanson, Roy Payne
  • Patent number: 7770528
    Abstract: A solid fuel burner and its combustion method suited for encouraging fuel ignition and avoiding slugging caused by combustion ash, wherein a gas of low oxygen concentration (exhaust combustion gas) is used as a carrier gas of such a low grade solid fuel as brown coal. An additional air nozzle for jetting additional air having a velocity component in the circumferential direction of a fuel nozzle is provided in the fuel nozzle, thereby encouraging mixing between the fuel and air in the fuel nozzle. Further, the amount of air supplied from the additional air nozzle is adjusted in response to the difference in combustion loads. Under light load, the amount of air supplied from the additional air nozzle is increased so as to increase the oxygen concentration of the circulating flow formed downstream of the outside of the outlet of the fuel nozzle, whereby stable combustion is ensured.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: August 10, 2010
    Assignee: Babcock- Hitachi K.K.
    Inventors: Hirofumi Okazaki, Kenji Yamamoto, Kenji Kiyama, Kouji Kuramashi
  • Publication number: 20100154689
    Abstract: A head assembly 52, 152 for a pulverized coal nozzle includes removeable wear-resistant inserts having vanes 54, 151, 153. The vanes 54, 151, 153 may be flat or curved to direct a stream of air and pulverized solid fuel particles from the inlet port 60, 160 toward the outlet port 62, 162. The curved vanes 151, 153 curve in two dimensions to evenly distribute the stream of air and pulverized solid fuel away from the outer surfaces reducing wear and corrosion. The pipe elbow has a removable cover 70, 170 that allows for easy access. The vanes are attached to a wear-resistant replaceable liner 185 thus allowing them to be easily removed and replaced. The wear-resistant liner 185 may be made from several parts 187, 189 for ease of removal and replacement.
    Type: Application
    Filed: November 2, 2009
    Publication date: June 24, 2010
    Applicant: ALSTOM TECHNOLOGY LTD
    Inventors: Daniel J. Adam, Oliver G. Briggs, Jr., Thomas J. Campanelli, Paul M. Colson, Christopher D. Curl, Dai Q. Dau, Wendell H. Mills
  • Patent number: 7739967
    Abstract: A pulverized solid fuel nozzle assembly 34 includes a fuel feed pipe 38 and a nozzle tip 36 pivotally secured relative to the fuel feed pipe 38. The fuel feed pipe 38 includes a generally cylindrical shell 99 having a round outlet end 102 and a bulbous protrusion 106 disposed around a perimeter of the round outlet end 102. The nozzle tip 36 includes an inner shell 40 having a round inlet end 108 arranged in concentric relationship with the round outlet end 102 of the generally cylindrical shell 99. The round inlet end 108 is disposed around the bulbous protrusion 106 for forming a seal between the inner shell 40 and the fuel feed pipe 38. The nozzle tip 36 also includes an outer shell 39 arranged in coaxial relationship with the inner shell 40, and an annular air channel 42 disposed between the inner and outer shells 40, 39. The nozzle tip 36 is pivotable about at least one axis 52, 250 for directing a stream of pulverized solid fuel from the inner shell 40.
    Type: Grant
    Filed: April 10, 2006
    Date of Patent: June 22, 2010
    Assignee: ALSTOM Technology Ltd
    Inventors: Oliver G. Briggs, Jr., Kevin E. Connolly, Kevin A. Greco, Philip H. Lafave, Galen H. Richards
  • Publication number: 20100143852
    Abstract: A method to regulate overfire air passing through an overfire air duct and entering a flue gas stream in a combustion system including: directing overfire air into an inlet of the overfire air duct, passing the overfire air through the duct and discharging the overfire air into the flue gas stream in the combustion system; adjusting a flow rate of overfire air entering the inlet using a damper adjacent the inlet, and moving the damper parallel along an axis of the overfire air duct to increase and decrease the overfire air entering the inlet, wherein the damper has an open position at which the damper is extended out of the inlet and a closed position in which the damper is substantially in the inlet and blocking air entering the inlet.
    Type: Application
    Filed: February 23, 2010
    Publication date: June 10, 2010
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Robert W. Waltz, Quang H. Nguyen
  • Patent number: 7717701
    Abstract: A burner includes a first oxidant conduit to transmit a first stream of an oxidant; a solid fuel conduit having an outtake and surrounding the first oxidant conduit, thereby forming a first annulus to transmit a mixture of a transport gas and particles of a solid fuel; a second oxidant conduit surrounding the solid fuel conduit, thereby forming a second annulus to transmit a second stream of the oxidant or an other oxidant; and means for segregating the mixture proximate the outtake into a lean fraction stream and a dense fraction stream. The first stream of the oxidant exiting the first oxidant conduit combines during combustion with the lean fraction stream, thereby forming an inner combustion zone adjacent the outtake, and the second stream of the oxidant, or the other oxidant, exiting the second oxidant conduit combines during combustion with the dense fraction stream, thereby forming an outer combustion zone.
    Type: Grant
    Filed: October 24, 2006
    Date of Patent: May 18, 2010
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Mark Daniel D'Agostini, Francis Anthony Milcetich
  • Patent number: 7665408
    Abstract: A solid fuel burner using a low oxygen concentration gas as a transporting gas of a low grade solid fuel such as brown coal or the like and a combustion method using the solid fuel burner are provided. The solid fuel burner comprises a means for accelerating ignition of the fuel and a means for preventing slugging caused by combustion ash from occurring. Mixing of fuel and air inside a fuel nozzle 11 is accelerated by that an additional air nozzle 12 and a separator 35 for separating a flow passage are arranged in the fuel nozzle 11, and the exit of the additional air nozzle 12 is set at a position so as to overlap with the separator 35 when seeing from a direction perpendicular to a burner axis, and additional air is ejected in a direction nearly perpendicular to a flow direction of a fuel jet flowing through the fuel nozzle 11. An amount of air from the additional air nozzle 12 is varied corresponding to a combustion load.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: February 23, 2010
    Assignees: Hitachi, Ltd., Babcock-Hitachi K.K.
    Inventors: Hirofumi Okazaki, Masayuki Taniguchi, Toshikazu Tsumura, Yoshitaka Takahashi, Kouji Kuramashi
  • Publication number: 20100024698
    Abstract: An initial coal feedstock comprised of primary or second coal is cleaned so as to reduce its ash content by at least about 20% in order to yield a refined coal product that produces fewer NOx emissions. The reduced NOx emissions result primarily from the ability to use less primary combustion air in order to maintain the pulverized refined coal in a suspended condition within the feeder pipes of a coal burner compared to the minimum quantity of air required to maintain pulverized coal from the initial coal feedstock in a suspended condition within the feeder pipes. Reducing the primary combustion air reduces the amount of oxygen in the primary combustion zone that would otherwise be available for converting fuel nitrogen into NOx. Instead, more of the fuel nitrogen is converted into N2. Reducing the primary combustion air also reduces the temperature of the core flame, reducing thermal NOx formation.
    Type: Application
    Filed: July 30, 2008
    Publication date: February 4, 2010
    Applicant: HEADWATERS ENERGY SERVICES CORPORATION
    Inventors: Rafic Minkara, N. Stan Harding
  • Publication number: 20100018445
    Abstract: A burner includes a primary air-coal mixture duct coaxially extended through a secondary air wind box, a pulverized coal separator supported within the primary air-coal mixture duct, a secondary air duct including an inner secondary air duct and an outer secondary air duct coaxially formed around the primary air-coal mixture duct, a primary air-coal mixture conical outlet coupled with the outlet of the primary air-coal mixture duct, and inner secondary air and outer conical outlets coupled with the outlets of the inner secondary air and outer secondary air ducts respectively. The conical outlets are arranged to delay the mixing time of the primary air-coal mixture and secondary air flows through the primary air-coal mixture and secondary air ducts and to prolong the residence time in the center recirculation zone under the reduction ability so as to effectively reduce the formation of NOx.
    Type: Application
    Filed: July 18, 2007
    Publication date: January 28, 2010
    Applicant: HARBIN INSTITUTE OF TECHNOLOGY
    Inventors: Zhenggi Li, Zhichao Chen, Rui Sun, Shaozeng Sun, Shaohua Wu, Ming Qin, Yunkun Qin
  • Publication number: 20090297996
    Abstract: A fuel injector for use in a furnace causes a primary stream of a carrier gas and fuel to be mixed with heated air, oxygen or a mixture of oxygen and CO2 or re-circulated flue gas, within the injector by a secondary stream of heated air, before the primary stream exits the injector as a fuel stream and flows into a combustion zone of the furnace. The interaction of the primary stream with the heated air of the secondary stream increases stoichiometry at the center of the fuel stream exiting the injector, so as to minimize NOx creation and maximize combustion of fuel in the furnace.
    Type: Application
    Filed: May 28, 2008
    Publication date: December 3, 2009
    Applicant: Advanced Burner Technologies Corporation
    Inventors: Joel Vatsky, Jiefeng Shan
  • Patent number: 7624707
    Abstract: An over fire air (OFA) port arrangement for a pulverized coal-fired boiler or furnace has at least one OFA port through each of the sidewalls for injecting OFA to increase residence time for each burner level. Plural OFA ports may be employed, staggered both vertically and horizontally to effectively deliver over fire air to the burner flames at the appropriate time and location to most efficiently reduce the formation of fuel NOx. OFA port configurations for both single-wall and opposed-wall fired furnaces and boilers are provided.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: December 1, 2009
    Assignee: Babcock & Wilcox Power Generation Group, Inc.
    Inventor: Albert D. LaRue
  • Patent number: 7591648
    Abstract: A burner assembly includes a fuel nozzle and an air-fuel mixing cone coupled to the fuel nozzle. Fuel is discharged from the fuel nozzle into a mixing chamber formed in the air-fuel mixing cone. Air passes into the mixing chamber through openings formed in the air-fuel mixing chamber and mixes with fuel to form a combustible air-fuel mixture in the air-fuel mixing chamber.
    Type: Grant
    Filed: September 13, 2007
    Date of Patent: September 22, 2009
    Assignee: Maxon Corporation
    Inventor: Pawel Mosiewicz
  • Publication number: 20090084294
    Abstract: A method and apparatus for reducing NOx emissions in a coal burning furnace of a power plant without utilizing techniques downstream of the furnace, such as SCR and SNCR, is provided. In a primary combustion zone, a fuel is combusted in the presence of a first oxidant gas comprised substantially of N2, to produce a first effluent gas that include one or more NOx species. Downstream a re-burn zone is operated in a sub-stoichiometric manner, combusting a second fuel in presence of the first effluent gas and a second oxidant wherein the second oxidant gas comprises a stream of oxygen. The effluent gas from the re-burn zone is introduced to overfire airflow so as to establish a super-stoichiometric zone prior to discharged from the furnace.
    Type: Application
    Filed: November 15, 2007
    Publication date: April 2, 2009
    Inventor: Hamid Sarv
  • Publication number: 20080127869
    Abstract: A low NOx Cyclone furnace steam generator including redesigned or modified Cyclone furnaces, air flow distribution, and new or relocated air ports maintains and/or minimizes NOx emission levels from the Cyclone furnace steam generator while minimizing Cyclone furnace and steam generator furnace tube wastage.
    Type: Application
    Filed: February 6, 2006
    Publication date: June 5, 2008
    Inventors: Gerald J. Maringo, George H. Harth, Manvil O. Dahl, Linda P. Dahl, Steven N. Burge, Rosemary Burge, Mitchell W. Hopkins
  • Patent number: 7213522
    Abstract: A solid fuel burner and its combustion method suited for encouraging fuel ignition and avoiding slugging caused by combustion ash, wherein a gas of low oxygen concentration (exhaust combustion gas) is used as a carrier gas of such a low grade solid fuel as brown coal. Means for Solving the Subject An additional air nozzle 12 for jetting additional air having a velocity component in the circumferential direction of a fuel nozzle 11 is provided in the fuel nozzle 11, thereby encouraging mixing between the fuel and air in the fuel nozzle 11. Further, the amount of air supplied from the additional air nozzle 12 is adjusted in response to the difference in combustion loads. Under light load, the amount of air supplied from the additional air nozzle 12 is increased so as to increase the oxygen concentration of the circulating flow 19 formed downstream of the outside of the outlet of the fuel nozzle 11, whereby stable combustion is ensured.
    Type: Grant
    Filed: November 9, 2004
    Date of Patent: May 8, 2007
    Assignee: Babcock-Hitachi K.K.
    Inventors: Hirofumi Okazaki, Kenji Yamamoto, Kenji Kiyama, Kouji Kuramashi
  • Patent number: 7168374
    Abstract: A solid fuel burner using a low oxygen concentration gas as a transporting gas of a low grade solid fuel such as brown coal or the like and a combustion method using the solid fuel burner are provided. The solid fuel burner comprises a means for accelerating ignition of the fuel and a means for preventing slugging caused by combustion ash from occurring. Mixing of fuel and air inside a fuel nozzle 11 is accelerated by that an additional air nozzle 12 and a separator 35 for separating a flow passage are arranged in the fuel nozzle 11, and the exit of the additional air nozzle 12 is set at a position so as to overlap with the separator 35 when seeing from a direction perpendicular to a burner axis, and additional air is ejected in a direction nearly perpendicular to a flow direction of a fuel jet flowing through the fuel nozzle 11. An amount of air from the additional air nozzle 12 is varied corresponding to a combustion load.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: January 30, 2007
    Assignees: Hitachi, Ltd., Babcock-Hitachi K.K.
    Inventors: Hirofumi Okazaki, Masayuki Taniguchi, Toshikazu Tsumura, Yoshitaka Takahashi, Kouji Kuramashi
  • Patent number: 7143610
    Abstract: A method and system feed and burn pulverized fuel, such as petroleum coke, in a glass melting furnace having burners associated with sealed regenerative chambers which act as heat exchangers. The system supplies the pulverized fuel for melting glass raw materials. The emissions of flue gases produced by the combustion process of the fuel in the furnace are controlled in order to maintain clean the flue gases and for reducing the emission of impurities from the fuel such as SOx, NOx, and particulates. The regenerative chambers are manufactured with selected refractories such as magnesium, zircon-silica-alumina, or magnesia and zirconium-silicate, for counteracting the erosive and corrosive effects produced by the combustion process of the fuel in the glass melting chamber. A burner feeds the petroleum coke and simultaneously mixes a primary air and pulverized fuel-air mixture for the burning of the pulverized fuel.
    Type: Grant
    Filed: November 18, 2003
    Date of Patent: December 5, 2006
    Assignee: Vitro Global, S.A.
    Inventors: Roberto Marcos Cabrera-Llanos, Rafael Valadez-Castillo, Arturo Keer-Rendon
  • Patent number: 7059256
    Abstract: The invention relates to an arrangement (1) for the combustion of granular, solid fuel, for example wood-flour pellets, chips and the like, comprising a preferably horizontal combustion chamber (16), a dispensing unit (3) for feeding the fuel into the combustion chamber via fuel feed pipe (15), air inlets (22, 23) with blower (18) for the delivery of primary air (P) to the combustion chamber via at least one air duct or air chamber (24, 25) in order to produce a flow of air through the combustion chamber and the fuel for a primary combustion of the fuel to combustion gases, and for the delivery of secondary air (S) to a secondary combustion chamber (26) via a secondary air distributor (26A) in order to produce a secondary combustion of the combustion gases formed in the primary combustion together with a common outlet (47) for the primary air, the combustion gases and the secondary air from the secondary combustion chamber to a boiler space (12) in a broiler (2) for transmitting the heat from the said primary
    Type: Grant
    Filed: April 26, 2002
    Date of Patent: June 13, 2006
    Assignee: Swedish Bioburner System Aktiebolag
    Inventor: Robert Ingvarsson
  • Patent number: 7028622
    Abstract: A burner assembly combines oxygen and fuel to produce a flame. The burner assembly includes an oxygen supply tube adapted to receive a stream of oxygen and a fuel supply tube arranged to extend through the oxygen tube to convey a stream of fluidized, pulverized, solid fuel into a flame chamber. Oxygen flowing through the oxygen supply tube passes through oxygen-injection holes formed in the fuel supply tube and then mixes with fluidized, pulverized, solid fuel passing through the fuel supply tube to create an oxygen-fuel mixture in a downstream portion of the fuel supply tube. This mixture is discharged into the flame chamber and ignited in a flame chamber to produce a flame.
    Type: Grant
    Filed: April 4, 2003
    Date of Patent: April 18, 2006
    Assignee: Maxon Corporation
    Inventor: Curtis L. Taylor
  • Patent number: 7021222
    Abstract: The present application disclosed an ignition and burning apparatus used in a coal boiler, comprising a pulverized coal burner and one or more combustion-enhancing miniature oil guns inserted in the pulverized coal burner, wherein the miniature oil gun comprises a first air supplying cylinder, an atomizing nozzle positioned in the first air supplying cylinder, an oil burner at a lower end of the atomizing nozzle, an ignition device adjacent to the oil burner and an air intake communicating with the first air supplying cylinder, wherein the pulverized coal burner comprises a cooling air cylinder, an air intake communicating with the cooling air cylinder, an expansion channel supported in the cooling air cylinder by a support, cooling structures surrounding the expansion channel, an external nozzle at one end of the expansion channel and a second air supplying cylinder adjacent to the miniature oil gun and communicating with the expansion channel.
    Type: Grant
    Filed: August 26, 2002
    Date of Patent: April 4, 2006
    Inventors: Aisheng Wang, Dong Tian
  • Patent number: 6889619
    Abstract: A solid fuel burner and method uses a low oxygen concentration gas as a transporting gas for a low grade solid fuel such as brown coal or the like, provides for accelerating ignition of the fuel and for preventing slugging caused by combustion ash. Mixing of fuel and air inside a fuel nozzle 11 is accelerated by an additional air nozzle 12 and a separator 35 for separating a flow passage, arranged in the fuel nozzle 11, and an exit of the additional air nozzle 12 is set at a position that overlaps with the separator 35. Additional air is ejected in a direction nearly perpendicular to a flow direction of a fuel jet flowing through the fuel nozzle 11. The amount of air from the additional air nozzle 12 is varied corresponding to a combustion load, in order to assure stable burning of the fuel, and, to suppress radiant heat received by structures of the solid fuel burner and walls of the furnace.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: May 10, 2005
    Assignees: Hitachi, Ltd., Babcock- Hitachi K.K.
    Inventors: Hirofumi Okazaki, Masayuki Taniguchi, Toshikazu Tsumura, Yoshitaka Takahashi, Kouji Kuramashi
  • Patent number: 6865994
    Abstract: An overfire air injector for use in a fossil fuel-fired combustion device includes a cylindrical nozzle having an outlet end formed with a step diffuser comprising one or more radial steps that enlarge the outlet end of the nozzle. An atomizer lance may be mounted within the nozzle, having a discharge orifice at the outlet end of the nozzle, for supplying a reducing agent to the overfire air to reduce NOx emissions.
    Type: Grant
    Filed: April 3, 2003
    Date of Patent: March 15, 2005
    Assignee: General Electric Company
    Inventors: William Randall Seeker, Roy Payne, Larry William Swanson
  • Publication number: 20040184974
    Abstract: Disclosed is a method of treating, fly ash having an unacceptably high concentration of carbon, with ozone produced in situ by corona discharge. This method will allow high carbon-content fly ash to be used with air entrainment agents as an additive to cement. The corona discharge can be produced in the exhaust pipe with a venturi of various combustion systems. The device of this invention can be used in conjunction with a triboelectric carbon-fly ash separation system or in a conventional combustion system. The corona discharge is produced off of sharp-tipped metal devices. A venturi is used in the exhaust pipe in the exhaust pipe in conjunction with the sharp-tipped metal devices.
    Type: Application
    Filed: February 19, 2004
    Publication date: September 23, 2004
    Applicant: ELECTRIC POWER RESEARCH INSTITUTE, INCORPORATED
    Inventors: Ralph F. Altman, Sam Rosen
  • Patent number: 6718889
    Abstract: A multi-fuel boiler having multiple, independent draft or combustion air sources and controls. A conventional oil/gas burner and nozzle assembly is fitted to an injector tube and isolated from a thermal transfer medium. A butterfly valve is supported in the injector tube and a motorized linkage directs valve operation. When the burner is non-operational, the valve prevents secondary combustion air from passing through the oil/gas burner to effect combustion in the firebox.
    Type: Grant
    Filed: August 30, 2002
    Date of Patent: April 13, 2004
    Assignee: Central Boiler, Inc.
    Inventors: Dennis Brazier, Mark Jeremy Reese, Rodney Lyle Tolefson
  • Patent number: 6715432
    Abstract: According to a burner of the present invention, a stable combustion is obtained in a wide range from a high-load operation condition to a low-load operation condition even in the case of low quality solid fuel such as brown coal. The amount of air supplied from additional air holes or additional air nozzles 12 can be adjusted depending on the combustion load of furnace 41. At a low load, the amount of air supplied from additional air holes or additional air nozzles 12 is increased, whereby the oxygen concentration in a recirculation zones 19 formed downstream of the outside of a fuel nozzle 11 exit, permits a stable combustion. At a high load, the amount of air supplied from additional air holes or additional air nozzles 12 is reduced, whereby a flame is formed in a position far from the fuel nozzle 11. This suppresses thermal radiation onto a solid fuel burner 42 structure and a furnace 41 wall.
    Type: Grant
    Filed: March 19, 2002
    Date of Patent: April 6, 2004
    Assignee: Babcock-Hitachi Kabushiki Kaisha
    Inventors: Toshikazu Tsumura, Hirofumi Okazaki, Miki Shimogori, Kenji Kiyama, Kouji Kuramashi, Hitoshi Kikuchi, Yoshitaka Takahashi, Shigeki Morita, Kazuhito Sakai, Masayuki Taniguchi, Hironobu Kobayashi
  • Patent number: 6659024
    Abstract: A powdery fuel combustion apparatus disposed on furnace side plane (7) of vertical square body type furnace in which a vertical plane passing through a fuel jetting directional axis (8) does not cross the furnace side plane orthogonally, and thus the workability of furnace wall tubes and burner panel, and the maintainability of burner nozzle are improved. The apparatus includes a burner nozzle (1) that is formed such that the nozzle has right and left non-symmetrical shapes, with respect to a vertical plane passing through axis (8). Also, the nozzle has a tip portion opening lying in an opening plane (2) which coincides or is parallel to the furnace side plane (7).
    Type: Grant
    Filed: October 13, 1999
    Date of Patent: December 9, 2003
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Tadashi Gengo, Kouichi Sakamoto, Masashi Hishida, Tomomitsu Yokoyama, Akiyasu Okamoto
  • Publication number: 20020144636
    Abstract: According to a burner of the present invention, a stable combustion is obtained in a wide range from a high-load operation condition to a low-load operation condition even in the case of low quality solid fuel such as brown coal.
    Type: Application
    Filed: March 19, 2002
    Publication date: October 10, 2002
    Inventors: Toshikazu Tsumura, Hirofumi Okazaki, Miki Shimogori, Kenji Kiyama, Kouji Kuramashi, Hitoshi Kikuchi, Yoshitaka Takahashi, Shigeki Morita, Kazuhito Sakai, Masayuki Taniguchi, Hironobu Kobayashi
  • Patent number: 6439136
    Abstract: A (MRFC) solid fuel nozzle tip (12) that is particularly suited to being cooperatively associated with a pulverized solid fuel nozzle (34) of a firing system of the type employed in a pulverized solid fuel-fired furnace (10). The MRFC solid fuel nozzle tip (12) includes fuel air shroud means (46), primary air shroud means (48) located within the fuel air shroud means (46), fuel air shroud support means (50) operative for supporting the primary air shroud means (48) relative to the fuel air shroud means (46), and splitter plate means (52) mounted in supported relation within the primary air shroud means (48). The MRFC solid fuel nozzle tip (12) may be comprised of ceramics including silicon nitride, siliconized silicon carbide, mullite bonded silicon carbide alumina composite, and alumina zirconia composites.
    Type: Grant
    Filed: July 3, 2001
    Date of Patent: August 27, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventors: Jeffrey S. Mann, Ronald H. Nowak
  • Patent number: 6389998
    Abstract: A fuel selected from powder fuels and liquid fuel is ejected through a fuel ejection pipe having an annular ejection opening; primary air is ejected through primary air-ejecting openings arranged on outer and inner sides of the fuel ejection, to form outer and inner primary air-ejection straight streams between which the fuel ejection stream is interposed, and to burn the fuel ejection stream. When a powder fuel is used, optionally, a liquid fuel is further ejected and mixed with the above-mentioned primary air streams, and the liquid and powder fuels are burnt together.
    Type: Grant
    Filed: February 9, 2001
    Date of Patent: May 21, 2002
    Assignee: Sumitomo Osaka Cement Co., Ltd.
    Inventors: Katsuji Mukai, Yoshihiko Sumitani, Toshiyuki Ishinohachi
  • Patent number: 6379146
    Abstract: A flow divider for use in a gas burner assembly supported in an opening in a furnace wall has injected fluid, such as gas and/or air, flowing through an inner burner pipe then outwardly through a plurality of openings for burning along the surface of a wall thus providing a near uniform radiant heat energy to the furnace. The flow divider has a plurality of nested members and a plurality of in-line members to divide the flowing gas and/or air to improve distribution and to promote more uniform mixing of the gas and air.
    Type: Grant
    Filed: April 9, 2001
    Date of Patent: April 30, 2002
    Assignee: Zeeco, Inc.
    Inventors: Darton J. Zink, Rex K. Isaacs, John McDonald, Tim Kirk
  • Patent number: 6367394
    Abstract: A pulverized fuel combustion burner and furnace arrangement has a plurality of air nozzles arranged on a side wall of the furnace for injecting a mixed flow of pulverized fuel and carrier air to establish a flame into the furnace. The plurality of nozzles includes a primary nozzle for injecting the mixed flow into the furnace and a secondary nozzle positioned around the primary nozzle for feeding combustion auxiliary air around the primary nozzle. A pulverized fuel supply pipe feeds the mixed flow to the primary nozzle. The primary nozzle and the pulverized fuel supply pipe are joined at a jointed portion at which the primary nozzle can be pivoted to change a direction for injecting the mixed flow into the furnace. The pulverized fuel supply pipe extends through a windbox, the windbox forming a combustion auxiliary air supply passage around the pulverized fuel supply pipe.
    Type: Grant
    Filed: September 19, 2000
    Date of Patent: April 9, 2002
    Assignee: Mitsubishi Heavy Industries
    Inventors: Shouzo Kaneko, Tadashi Gengo, Kouichi Sakamoto, Takayoshi Isoda
  • Patent number: 6347937
    Abstract: A direct coal fired burner system for a rotary kiln in which the burner has a multi-barrel construction through which primary air for conveying coal is heated with tertiary air sourced from the rotary kiln, and the shape of the emerging flame is controlled by a first annulus of swirling tertiary air adjacent the primary airstream and by a second annulus of laminar tertiary air defining an outer envelope for the flame. The volume and relative velocities of air in the tertiary air supplies are all controllable through the use of respective dampers provided in tertiary air supply conduits.
    Type: Grant
    Filed: January 21, 2000
    Date of Patent: February 19, 2002
    Assignee: ATS Spartec Inc.
    Inventors: Bruce Yearham, Gerald Plant
  • Patent number: 6298796
    Abstract: A burner for burning fine coal powder comprising: a fine coal powder nozzle 10 for injecting a mixture of the fine coal powder and air; and air nozzles 11, 12 for injecting air: wherein the sufficient amount of air for complete combustion of the fine coal powder is supplied from the air nozzles; a reducing flame at a high temperature is formed by consuming oxygen rapidly with forming a flame at a high temperature by igniting the fine coal powder rapidly in the vicinity of the outlet of the burner; and an oxidizing flame having an uniform distribution of gas composition in radial direction to the central axis of the burner is formed by mixing the air injected from the air nozzle in the downstream of the reducing flame at the high temperature.
    Type: Grant
    Filed: March 1, 2000
    Date of Patent: October 9, 2001
    Assignees: Hitachi, Ltd., Babcock-Hitachi Kabushiki Kaisha
    Inventors: Hirofumi Okazaki, Hironobu Kobayashi, Toshikazu Tsumura, Kenji Kiyama, Tadashi Jinbo, Koji Kuramashi, Shigeki Morita, Shinichiro Nomura, Miki Shimogori
  • Patent number: 6293208
    Abstract: In a method of supplying air to a pulverized solid fuel burner passing through the burner cowl of a furnace, the fuel is dried and then conveyed by means of a given large quantity of hot air, which may or may not be depleted in oxygen in a separator in which the fuel is extracted from it. The fuel is then conveyed to the burner by means of a first portion only of the air from which the fuel has been removed. This conveyor air portion is used as primary combustion-supporting air for burning the fuel in the burner, into which the first portion of air, mixed with the fuel it conveys, is fed via an annular duct. The other portion of the hot air purified in the separator is used at least as additional primary combustion-supporting and flame adjustment air and is fed into the burner peripherally and centrally relative to the first portion of air charged with fuel.
    Type: Grant
    Filed: January 20, 2000
    Date of Patent: September 25, 2001
    Assignee: Entreprise Generale de Chauffage Industriel Pillard
    Inventors: Roland Guiot, Luigi Russo, Jean-Claude Gauthier, Jean-Claude Pillard