Oxidizer Added To Region Of Incomplete Combustion Patents (Class 431/10)
  • Patent number: 6283747
    Abstract: The invention relates to a method for heating a furnace comprising at least one burner capable of operating on an oxidant the oxygen content of which can vary; in a first period (P1) the burner is supplied with practically pure oxygen so as to provide a large amount of energy for heating, in a second period (P2) the burner is supplied with an oxidant, the oxygen content of which can vary between about 100% and 21%, in a third period (P3), the burner is supplied with an oxidant, the oxygen content of which is minimal, and which corresponds to a pilot period which requires only a small amount of heating energy. This method makes it possible to optimize the use of the furnace according to the desired thermal performance and oxidant operating costs.
    Type: Grant
    Filed: September 20, 1999
    Date of Patent: September 4, 2001
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Thierry Legiret, GĂ©rard Le Gouefflec, Thierry Borissoff, Olivier Charon
  • Publication number: 20010018171
    Abstract: There exists a tendency in the construction of combustion devices to employ a multi-level, spatially distributed feed of the combustion air in order to be able to better influence the stoichiometric ratios during the combustion. These solutions are little suited for the compact construction and, in addition, the flame temperature is too high in the region of the air feed relative to a low NOx combustion if one does not employ expensive constructions with additional cooling bodies.
    Type: Application
    Filed: December 17, 1997
    Publication date: August 30, 2001
    Inventor: AHMAD AL-HALBOUNI
  • Patent number: 6279495
    Abstract: A method and an apparatus for optimizing the combustion air system in a power boiler or chemical recovery boiler by improving fluid flow and gas mixing are disclosed, whereby one can increase boiler capacity and combustion uniformity and reduce particulate and gaseous emissions. The method involves interlacing of the secondary and, where applicable, the tertiary air supply through opposing air ports on all four walls of the boiler, and is implemented by alternately opening wide or partially closing a port damper on one side, while partially closing or opening wide a port damper on the opposite side, such that a 70-100% open damper on one side opposes a partially closed (10-40% open) damper on the other and vice versa in an alternating fashion, along opposing walls.
    Type: Grant
    Filed: July 3, 2000
    Date of Patent: August 28, 2001
    Assignee: Pulp and Paper Research Institute of Canada
    Inventors: Ibrahim Karidio, Victor Uloth, Klaus Weiss
  • Publication number: 20010010896
    Abstract: Provision of a low-NOx burner allowed to further reduce NOx only by structural design of the burner in comparison with prior art. The low-NOx burner comprises a main nozzle 13 for injecting a premixture formed by mixing fuel and an oxidizer, and a secondary flame-holding nozzle 12A for making a premixture or an oxidizer impinge on the premixture injected from the main nozzle 13, in a direction at an approximately right angle to the injection direction of the main nozzle 13.
    Type: Application
    Filed: December 20, 2000
    Publication date: August 2, 2001
    Applicant: TOKYO GAS CO., LTD
    Inventors: Satoshi Nagayama, Shin Shizukuishi
  • Patent number: 6267586
    Abstract: The inventive burner can receive air and fuel and discharge a fuel/air mixture for combustion at a periphery of the burner while limiting NOx emissions. The burner has a central axis and includes first and second plates constructed and arranged so as to form between them a central chamber and a plurality of burner ports extending outwardly of the chamber. The first and second plates have an outer periphery spaced outwardly from the central axis. The second plate indudes an opening for receiving the air and fuel into the chamber. The outer periphery of the second plate extends from the central axis by a greater distance than the outer periphery of the first plate. The second plate has an outer peripheral portion in which a plurality of openings may be formed. Also included is a method for operating the burner so as to limit NOx emissions.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: July 31, 2001
    Assignee: Beckett Gas, Inc.
    Inventor: Richard Maricic
  • Patent number: 6267585
    Abstract: A plate burner for combusting hydrogen with air as an oxidizer forms a wall portion of a combustion chamber for example of a gas turbine. The plate burner is so constructed that air and hydrogen are separately guided to the downstream surface area facing into the combustion chamber for forming a large number of diffusive microcombustion flames, thus achieving a very low mixing scale simultaneously with a high nixing intensity. The number of diffusive micorcombustion flames is so selected that the NOx content in the exhaust gas from the combustion chamber is at the most 10×10−6 cubic foot per cubic foot of exhaust gas. The hydrogen enters the entrance area into the combustion chamber either through a porous wall, and air is injected into the hydrogen environment to form inverse diffusive microcombustion flames or the hydrogen is injected through a multitude of fine holes into high velocity air jets forming regular diffusion flames.
    Type: Grant
    Filed: May 7, 1999
    Date of Patent: July 31, 2001
    Assignee: DaimlerChrysler Aerospace Airbus GmbH
    Inventor: Friedemann Suttrop
  • Patent number: 6238206
    Abstract: A burner (10) for use in both high O2 environments and low O2 environments comprises an outer tube (24) and an inner tube (26). The outer tube (24) defines a flow passage (53) and includes an inlet portion (42), an outlet portion (46), and a nozzle portion (44) interconnecting the inlet portion (42) and outlet portion (46). The inlet portion (42) has a larger effective cross-sectional area than the outlet portion (46) so that air (20) or an air-and-fuel mixture (35) moving through nozzle portion (44) is accelerated. The inner tube (26) is positioned to lie in the flow passage (53) of the outer tube (24) and is formed to include fuel-injection holes (78) to conduct fuel (33) into the flow passage (53).
    Type: Grant
    Filed: May 16, 2000
    Date of Patent: May 29, 2001
    Assignee: Maxon Corporation
    Inventors: William G. Cummings, III, Curtis L. Taylor
  • Patent number: 6237513
    Abstract: A method of operating a solid fuel-fired furnace having a plurality of windboxes each having a plurality of compartments through which fuel and air are introduced into the furnace and a fuel and air arrangement operated in accordance with the method are provided. Solid fuel is fed into the furnace and primary air and fuel are fed through the same compartments into the furnace in a direction tangential to a first imaginary circle generally located in the center of the furnace so as to interact with the fuel fed into the furnace so as to create a rotating fireball. Overfire air and offset air are also supplied into the furnace, the offset air being that portion of the air supplied to the furnace so as to support a second imaginary circle concentric to, and having a larger diameter than, the first imaginary circle.
    Type: Grant
    Filed: December 21, 1998
    Date of Patent: May 29, 2001
    Assignee: ABB Alstrom Power Inc.
    Inventors: Rebecca L. Tobiasz, Douglas J. Hart, Robert D. Lewis, James P. Sutton, Bruce F. Griffith
  • Patent number: 6234092
    Abstract: A process for the thermal treatment of incombustible liquids in a combustion space of a combustion apparatus by contacting the incombustible liquid with a supplementary fuel in the combustion space in the presence of at least one reactive gas. The process of the invention comprises feeding the incombustible liquid and the supplementary fuel into the combustion space (1) at different points, mixing the incombustible liquid with at least one reactive gas and the supplementary fuel with at least one inert gas prior to the contacting, and vaporizing the incombustible liquid and supplementary fuel prior to the contacting in the combustion space. The advantage of this invention is that environmentally harmful waste waters in particular are disposed of by burning these using a supplementary fuel. The required amounts of supplementary fuel are minimal in the process and only small amounts of nitrogen oxides, carbon monoxide and soot are generated.
    Type: Grant
    Filed: December 8, 1999
    Date of Patent: May 22, 2001
    Assignee: BASF Aktiengesellschaft
    Inventors: Thomas Domschke, Andreas Joa, Klaus Steinebrunner
  • Patent number: 6206685
    Abstract: Various methods for decreasing the amount of nitrogen oxides released to the atmosphere as a component of combustion gas mixtures are provided. The methods specifically provide for the removal of nitric oxide and nitrogen dioxide (NOx) from gas mixtures emitted from stationary combustion systems. In particular, methods for improving efficiency of nitrogen oxide reduction from combustion systems include injecting metal-containing compounds into the main combustion zone and/or the reburning zone of a combustion system. The metal containing compounds react with active combustion species, and these reactions change radical concentrations and significantly improve NOx conversion to molecular nitrogen. The metal-containing additives can be injected with the main fuel, in the main combustion zone, with secondary or reburning fuel addition, or at several locations in the main combustion zone and reburning zone.
    Type: Grant
    Filed: August 31, 1999
    Date of Patent: March 27, 2001
    Assignee: GE Energy and Environmental Research Corporation
    Inventors: Vladimir M. Zamansky, Peter M. Maly, Jerald A. Cole, Vitali V. Lissianski, William Randall Seeker
  • Patent number: 6206686
    Abstract: A low NOx burner and related method are disclosed including the steps of supplying a first reactant stream and introducing a second reactant stream into the first reactant stream at a first point so as to produce co-flowing streams. This resulting fuel/oxidant stream is discharged into a furnace environment having inert combustion products substantially equilibrated to furnace temperature, so as to entrain the combustion products and mix them together with the co-flowing stream. The temperature of the co-flowing stream is increased by the entrained products until it ignites in a combustion region displaced from the first point. Thus ignition cannot occur until the reactant stream has been diluted by inert products of combustion, reducing both oxygen concentration and peak flame temperature, so as to suppress NOx production.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: March 27, 2001
    Assignee: North American Manufacturing Company
    Inventors: Keith J. Nieszczur, Bruce E. Cain, John N. Newby, Thomas F. Robertson, Richard D. Sutton
  • Patent number: 6203314
    Abstract: Combustion assembly adapted to be placed in a wall of a furnace including an axis having at least one pair of burners with axes, one oxidant lance arranged between the burners of the pair and having a lance axis and a source of oxidant connected to the burners and to the lance.
    Type: Grant
    Filed: January 8, 1997
    Date of Patent: March 20, 2001
    Assignee: l'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Louis Philippe, Eric Duchateau, Dominique Jouvaud, Robert Plessier, Claude Pivard, Etienne Lepoutre
  • Patent number: 6202575
    Abstract: An air compartment of a corner windbox of a tangential firing system of a fossil fuel-fired furnace for injecting secondary air into the furnace. The air compartment includes a channel portion with an entrance end communicating with an air delivery duct and an exit end communicating via an exit assembly with the furnace opening. The exit assembly includes at least one vane for guiding an air stream and a mounting frame for supporting the vane relative to the channel portion for guiding thereby of an air stream passing from the channel portion through the furnace opening into the furnace. The vane includes a surface portion which intersects the horizontal plane at an acute angle and a pair of opposed transverse edges. The vane and the mounting frame are disposed within the channel portion such that the leading edge of the vane is upstream of the furnace opening.
    Type: Grant
    Filed: February 18, 1999
    Date of Patent: March 20, 2001
    Assignee: ABB Alstom Power Inc.
    Inventors: Wesley P. Bauver, II, Richard C. LaFlesh, John C. Lewis, Robert D. Lewis
  • Patent number: 6196831
    Abstract: The invention relates to a combustion process for burning a fuel, in which the point of injection of each main oxidizer jet (7, 8) with respect to the point of injection of a fuel jet (4) closest to it is arranged a distance D away satisfying the following relation: D A > 5 ⁢   ⁢ and / or ⁢   ⁢ D B > 5 D being the minimum distance between the outer edge of the relevant oxidizer jet (7, 8) and the outer edge of the fuel jet (4) closest to it, at their respective points of injection, A and B being, respectively, the cross section of the main jet (7, 8) of the oxidizer and the cross section of the fuel jet, considered at their respective points of injection.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: March 6, 2001
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Jacques Dugue, Jean-Michel Samaniego, Bernard Labegorre, Olivier Charon
  • Patent number: 6192811
    Abstract: An air nozzle for introducing secondary air into a furnace and including a housing provided with an inlet at one end thereof for receiving air and an outlet at the other end thereof for discharging the air. A damper is disposed in the housing in the path of the air for splitting the flow of the air into two flow streams which extend to different areas of the furnace and is adapted for pivotal movement in the housing to vary the amount of air flow in each of the streams and the discharge angle of one of the streams.
    Type: Grant
    Filed: February 15, 2000
    Date of Patent: February 27, 2001
    Assignee: Foster Wheeler Corporation
    Inventor: Joel Vatsky
  • Patent number: 6193502
    Abstract: The fuel is fed centrally into a fire tube (3), where it is mixed with combustion air in a combustion zone. The air exits through first and second air line nozzles (4 or 5) which are arranged in two directly adjoining rows (6, 7) and inclined in the direction of counterflow at an angle of 60° to the axis of the fire tube. The distance (x) between the fuel nozzle (9) and the openings of the first air line nozzles (4) is 0.70 times the diameter of the fire tube. In addition, the second air line nozzles (5) extend into the fire tube by a distance (y) which is 0.17 times the diameter of the fire tube. The total cross-section of the second air line nozzles (5) is 0.6 times that of the first air line nozzles (4). A highly turbulent toroidal eddy forms inside the fire tube (3) which generates a very homogeneous mixture across the cross-section of said fire tube (3). This results in lower NOx values and even temperature distribution already inside the fire tube.
    Type: Grant
    Filed: November 22, 1999
    Date of Patent: February 27, 2001
    Assignee: Ruhrgas Aktiengesellschaft
    Inventors: Anatolij Vladimirovic Sudarev, Jevgenij Dimitrijevic Vinogradov, Jurij Ivanovic Zacharov, Stanislav Vesely, Gustav Poslusny, Karl Peters, Karl-Heinz Scholz, Erik Zizow
  • Patent number: 6190160
    Abstract: The invention relates to a process for combustion of a fuel with an oxygen-rich oxidant, in a combustion chamber (3), in which, cyclically: at least one principal variable representing the combustion in the said combustion chamber (3) is measured, and, as a function of the result of the measurement of the at least one principal variable, a control instruction for regulating the flowrates of fuel and oxidant to be injected into the combustion chamber (3) is determined. Then the regulating control instruction is applied in order to make the fuel burn with the oxidant in the chamber (3). Additionally at least one secondary variable associated with an operational constraint of the combustion chamber (3) or with a perturbation in the operation of the latter is measured, and for the determination of regulating control instruction, the measurement result of the at least one secondary variable is also taken into account. The invention is useful in glass furnaces, rotary furnaces, and incineration furnaces.
    Type: Grant
    Filed: July 2, 1999
    Date of Patent: February 20, 2001
    Assignee: L'Air Liquide, Societe Anonyme pour pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Isabelle Hibon, Jean-Francois Simon
  • Patent number: 6186080
    Abstract: A boiler recovers a soda component from pulp spent liquor and is able to prevent carry-over of unburnt char and deformation of a char bed configuration and to attain a stable combustion with low NOx generation. By regulating the combustion air supply, and feeding inert gas along a furnace side wall around the char bed, there are formed a combustion zone of reduction atmospheric field where air ratio in the surroundings of the char bed is 0.8 or less, a combustion zone of reduction atmospheric field where air ratio is 1.0 or less and unburnt components exist (including the case of a reduction atmospheric field where air ratio is 1.0 or less and unburnt components exist with the two combustion zones being combined together) and a combustion zone where combustion is completed.
    Type: Grant
    Filed: November 6, 1997
    Date of Patent: February 13, 2001
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Hirokazu Hino, Toshimitsu Ichinose, Kimishiro Tokuda, Yoshihisa Arakawa, Masaaki Nagai, Yoshitaka Baba
  • Patent number: 6183240
    Abstract: A burner for operating a unit for generating a hot gas consists essentially of at least two hollow partial bodies (1, 2) which are interleaved in the flow direction and whose center lines extend offset relative to one another in such a way that adjacent walls of the partial bodies (1,2) form tangential air inlet ducts (5, 6) for the inlet flow of combustion air (7) into an internal space (8) prescribed by the partial bodies (1, 2). The burner has at least one fuel nozzle (11). In order to control flow instabilities in the burner, the inside of the burner outlet (17) has a plurality of nozzles (32) along the periphery of the burner outlet (17) for introducing axial vorticity into the flow, the nozzles (32) for injecting air (34) being arranged at an angle to the flow direction (30).
    Type: Grant
    Filed: November 12, 1999
    Date of Patent: February 6, 2001
    Assignee: ABB Research Ltd.
    Inventors: Klaus Döbbeling, Ephraim Gutmark, Christian Oliver Paschereit, Wolfgang Weisenstein
  • Patent number: 6159003
    Abstract: Combustion process in a furnace comprising a floor on which a charge to be heated is placed, and a roof lying above the charge, in which process the combustible fluid and the oxidizer fluid are injected separately between the surface of the charge and the roof, characterized in that the oxidizer and the fuel are injected at two different levels and in that the ratio of the impulsive forces (m.sub.2.v.sub.2 /m.sub.1.v.sub.1) of the combustible and oxidizer fluids is greater than or equal to approximately 1/3, m.sub.1 being the mass flow rate of the top fluid and v.sub.1, its velocity of injection into the furnace, m.sub.2 being the mass flow rate of the bottom fluid and v.sub.2 its velocity of injection into the furnace.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: December 12, 2000
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Thierry Duboudin, Bernard Labegorre
  • Patent number: 6148743
    Abstract: An air nozzle for introducing secondary air into a furnace and including a housing provided with an inlet at one end thereof for receiving air and an outlet at the other end thereof for discharging the air. A damper is disposed in the housing in the path of the air for splitting the flow of the air into two flow streams which extend to different areas of the furnace and is adapted for pivotal movement in the housing to vary the amount of air flow in each of the streams and the discharge angle of one of the streams.
    Type: Grant
    Filed: April 29, 1996
    Date of Patent: November 21, 2000
    Assignee: Foster Wheeler Corporation
    Inventor: Joel Vatsky
  • Patent number: 6142765
    Abstract: A process for burning fuel which is formed of free hydrocarbons and/or fine-grained to dusty solid fuels, with a view to obtaining thorough mixing of the oxygen with the fuel in a manner as free of turbulences as possible, is characterized in that, into a main jet of oxygen or an oxygen-containing gas which is approximately cylindrical or slightly conically widening in the jet direction, several fuel jets oriented in a skew manner relative to the central longitudinal axis of the main jet are blown, which fuel jets are formed to surround the main jet peripherally, penetrate into the main jet and are sucked into the main jet.
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: November 7, 2000
    Assignee: Vost-Alpine Industrieanlagenbau GmbH
    Inventors: Norbert Ramaseder, Johannes Muller, Stefan Dimitrov, Harald Berger, Johannes Steins
  • Patent number: 6138588
    Abstract: A method of operating a pulverized coal-firing furnace is provided which includes injecting air from an upper compartment generally in opposition to a swirling fireball. The method also provides the step of sensing a temperature characteristic of one side of a convection pass of the furnace. The sensed value, in accordance with the method of the present invention, is then evaluated to determine if the sensed value of the temperature characteristic exceeds an allowable value. In response to a determination that the temperature characteristic exceeds the allowable value, the momentum of the air injected through the upper air compartment is changed. After the step of changing the momentum of the air injected through the upper air compartment, the temperature characteristic of the one convection pass location is sensed to obtain a post adjustment value of the temperature characteristic and compared to an allowable value.
    Type: Grant
    Filed: August 10, 1999
    Date of Patent: October 31, 2000
    Assignee: ABB Alstom Power Inc.
    Inventors: Paul J. Chapman, Michael L. Kaplan, Majed A. Toqan
  • Patent number: 6138587
    Abstract: An arrangement for burning refuse in which the refuse is deposited on a grate and transported to a drop-out shaft. A part of the air supplied for burning the refuse is transmitted as primary air from below the grate. A part of the air is also blown into a combustion chamber as secondary air. The resulting flue gas from the combustion is moved in a direct or parallel stream with the refuse to an end region of the combustion chamber, and deflected in direction and injected through an opening in a flue gas channel having a vertical center plane and two channel halves on both sides of the plane. At least a secondary air stream is blown into blown channel halves in the region of the channel opening, mirror-symmetrically to the center plane. The second air stream is blown in with a rotary pulse relative to a center axis of a cross-section of the channel halves. Two oppositely rotating swirls are generated by the secondary air streams in the channel halves symmetrically to the vertical center plane.
    Type: Grant
    Filed: November 4, 1997
    Date of Patent: October 31, 2000
    Assignee: Deutsche Babcock Anlagen GmbH
    Inventors: Arvid Christmann, Bernd Rutten, Stefan Hartig, Dieter Wurz
  • Patent number: 6132202
    Abstract: The object of the invention is to provide a method and a device for operating a premix burner which improve the supply of fuel under certain types of operation.According to the invention, this is achieved by the fact that the liquid fuel (2) and the water (27) are conveyed separately to the liquid-fuel nozzle (17), and only there a liquid-fuel/water mixture (28) is produced, which is then injected into the inner chamber (9) of the premix burner (4) in a plain jet (29) with an injection angle a of less than 10.degree.. To this end and, the liquid-fuel nozzle (17), which opens out centrally into the inner chamber (9), is designed with a simple injection opening (19). A mixing zone (22), into which a liquid-fuel line (20) and a water feed line (21) open out, is arranged upstream of the injection opening (19).
    Type: Grant
    Filed: October 27, 1998
    Date of Patent: October 17, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Adnan Eroglu, Robin McMillan, Jens Policke
  • Patent number: 6126438
    Abstract: A burner apparatus comprises a conduit adapted to convey preheated oxidant and having outlet and inlet ends, and a conduit adapted to convey preheated fuel and having outlet and inlet ends. The conduit adapted to convey preheated fuel is substantially parallel to the conduit adapted to convey preheated oxidant. The conduit adapted to convey preheated oxidant is positioned substantially vertically above the conduit adapted to convey preheated fuel. The conduit adapted to convey preheated oxidant and the conduit adapted to convey preheated fuel each are positioned within its own respective elongate cavity in a refractory burner block. Each of the conduits are positioned in their respective cavity such that a substantially annular region is present between an outer surface of each conduit and its respective cavity. Each conduit inlet end extends through a respective plenum for receiving an ambient temperature fluid, the plenums adapted to pass the ambient temperature fluid into the respective annular regions.
    Type: Grant
    Filed: June 23, 1999
    Date of Patent: October 3, 2000
    Assignees: American Air Liquide, L'Air Liquide Societe Anonyme pour l'Etude et, l'Exploitation des Procedes Georges Claude
    Inventors: Mahendra L. Joshi, Arnaud Fossen, Harley A. Borders, Remi P. Tsiava, Olivier Charon
  • Patent number: 6120281
    Abstract: A combustion method in which a coal/primary air mixture is discharged from burners located in the corners of the furnace towards an imaginary circle disposed in the center of the furnace. Air is discharged from air nozzles also located in the corners of the furnace in two flow streams--one directed towards the center of the furnace in a combustion-supporting relation to the fuel, and the other along the inner surfaces of the furnace boundary walls to maintain an oxidizing atmosphere and minimize corrosion and slagging.
    Type: Grant
    Filed: July 23, 1997
    Date of Patent: September 19, 2000
    Inventor: Joel Vatsky
  • Patent number: 6109911
    Abstract: A method and an arrangement for reducing emissions of nitrogen oxides in a combustion apparatus provided with a tubular furnace. The method comprises burning odor gases at first sub-stoichiometrically, and subsequently supplying additional air to the furnace (3) in the transverse direction thereof in such a manner that the final air ratio is over 1. The arrangement comprises an additional air duct (7) which extends to the furnace of the boiler and from which additional air is supplied to the furnace (3) in the transverse direction of the furnace (3).
    Type: Grant
    Filed: October 7, 1998
    Date of Patent: August 29, 2000
    Assignee: Kvaerner Pulping Oy
    Inventors: Ari Tamminen, Risto Syrjalainen, Heikki Koivuniemi, Erkki Valimaki
  • Patent number: 6089855
    Abstract: A high efficiency, Vortex Inertial Staged Air (VIStA) combustor provides ultra-low NO.sub.X production of about 20 ppmvd or less with CO emissions of less than 50 ppmvd, both at 3% O.sub.2. Prompt NO.sub.X production is reduced by partially reforming the fuel in a first combustion stage to CO and H.sub.2. This is achieved in the first stage by operating with a fuel rich mixture, and by recirculating partially oxidized combustion products, with control over stoichiometry, recirculation rate and residence time. Thermal NO.sub.X production is reduced in the first stage by reducing the occurrence of high temperature combustion gas regions. This is achieved by providing the first stage burner with a thoroughly pre-mixed fuel/oxidant composition, and by recirculating part of the combustion products to further mix the gases and provide a more uniform temperature in the first stage. In a second stage combustor thermal NO.sub.
    Type: Grant
    Filed: July 10, 1998
    Date of Patent: July 18, 2000
    Assignee: Thermo Power Corporation
    Inventors: Frederick E. Becker, Ronald W. Breault, Anthony F. Litka, Andrew W. McClaine, Kailash Shukla
  • Patent number: 6085673
    Abstract: A method to reduce waterwall corrosion in a low NO.sub.x boiler includes the steps of locating a waterwall area of a low NO.sub.x boiler where oxidizing conditions exist and deposition of FeS is likely. The combustion air input at the waterwall area is biased to reduce FeS deposition on the waterwall. The biased combustion air input increases the oxidation rate of FeS.sub.2 so as to reduce FeS deposition on the waterwall. The biased combustion air input may be achieved by increasing the air-to-fuel ratio of one burner while reducing the air-to-fuel ratio of another burner, such that the overall air-to-fuel ratio in the low NO.sub.x boiler is substantially constant.
    Type: Grant
    Filed: June 18, 1998
    Date of Patent: July 11, 2000
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Wate T. Bakker, Anthony Facchiano
  • Patent number: 6085674
    Abstract: A method and apparatus for reducing NO.sub.x emissions from the combustion of carbonaceous fuels using three stages of oxidation. In the first stage, a partial oxidation combustor is used to partially combust the fuel in the presence of heated combustion air. The fuel gas produced in the partial oxidation process is passed to a second stage partial oxidation combustor while molten slag is removed and disposed of. A second preheated combustion air is introduced into the second stage combustor to produce a reducing flue gas. A third combustion air is mixed with the flue gas in a third stage combustor to substantially complete the combustion process. Preheated steam may be added at any or all of the combustion stages. The stochiometric ratios at each stage of combustion are controlled to minimize overall NO.sub.x emissions to acceptable levels.
    Type: Grant
    Filed: February 3, 1999
    Date of Patent: July 11, 2000
    Assignee: Clearstack Combustion Corp.
    Inventor: Robert A. Ashworth
  • Patent number: 6083466
    Abstract: Process for partial oxidation in a Claus furnace of at least one gas stream comprising hydrogen sulphide, comprising the steps of:(a) injecting at least one gas stream comprising hydrogen sulphide and at least one oxygen-enriched gas stream into the Claus furnace, wherein each of the streams is injected at a speed of injection which is substantially parallel,(b) controlling the speed of injection of the gas stream comprising hydrogen sulphide and the speed of injection of the oxygen-enriched gas stream such that the speeds have a ratio between 0.8 and 1.2.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: July 4, 2000
    Assignee: L'Air Liquide Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Ebrahim Djavdan, Jacques Koening, Jean-Fran.cedilla.ois Nicolas, Vincent Queudot, Olivier Charon
  • Patent number: 6082273
    Abstract: In a method for operating a corner burner of a tangential burner system, at least a first air stream of coal dust and primary air is tangentially introduced to a imaginary horizontal circle in the combustion chamber of the tangential burner system via a nozzle of the corner burner. An additional air stream is introduced into the combustion chamber in a direction toward a chamber wall of the combustion chamber at an adjustable offset angle relative to the first air stream. The offset angle can be adjusted by providing the additional air stream as mixed air stream of at least two partial air streams of different adjustable flow velocity. A first partial air stream within the nozzle flows straight into the outlet opening of the nozzle, and the second partial air stream flows angularly into the first partial air stream upstream of the outlet opening. The nozzle has a mixing chamber arranged upstream of the outlet opening.
    Type: Grant
    Filed: December 11, 1998
    Date of Patent: July 4, 2000
    Assignee: L. & C. Steinmuller GmbH
    Inventors: Werner Christ, Wolfgang Schreier
  • Patent number: 6079974
    Abstract: A combustion chamber is provided that has a vertically oriented body with an inner surface defining an inner combustion area. A burner is disposed adjacent one end of the body so that the flame of the burner when lit will extend into the combustion area. A first annular insert is disposed in the combustion area and generally surrounds the flame of the burner. The annular insert defines a first secondary gas introduction zone for introducing secondary gases into the combustion area so that the secondary gases can be oxidized by the burner flame. The insert has an inner surface presenting at least one opening for allowing fluid communication between the introduction zone and the combustion area. A second annular insert is disposed in the combustion area below the first insert. The second insert defines a secondary gas extraction zone and a second secondary gas introduction zone located below the extraction zone. The gas extraction zone and second secondary gas introduction zone are separated by a divider plate.
    Type: Grant
    Filed: October 14, 1997
    Date of Patent: June 27, 2000
    Assignee: Beloit Technologies, Inc.
    Inventor: Stanley P. Thompson
  • Patent number: 6077072
    Abstract: Superior heat transfer in a kiln is achieved by the use of at least one injector which injects both an oxidant, preferably containing oxygen, and a secondary fuel into the kiln. The injectors are provided so that the energy resulting from the combustion of the different fuels in the kiln heats specified regions of the kiln, without causing hot spots on the refractory walls. A firing scheme is described for the oxygen and fuels which allows an increase in the amount of heat released toward the load, resulting in significant increases in kiln efficiency and production. Low quality fuels may be used, as well as using and/or recycling more insufflated dust, without an adverse effect on the main flame.
    Type: Grant
    Filed: September 18, 1998
    Date of Patent: June 20, 2000
    Assignees: American Air Liquide Inc., L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Ovidiu Marin, Mahendra L. Joshi, Olivier Charon, Jacques Dugue
  • Patent number: 6074197
    Abstract: A burner assembly having improved flame length and shape control is presented, which includes in exemplary embodiments at least one fuel fluid inlet and at least one oxidant fluid inlet, means for transporting the fuel fluid from the fuel inlet to a plurality of fuel outlets, the fuel fluid leaving the fuel outlets in fuel streams that are injected into a combustion chamber, means for transporting the oxidant fluid from the oxidant inlets to at least one oxidant outlet, the oxidant fluid leaving the oxidant outlets in oxidant fluid streams that are injected into the combustion chamber, with the fuel and oxidant outlets being physically separated, and geometrically arranged in order to impart to the fuel fluid streams and the oxidant fluid streams angles and velocities that allow combustion of the fuel fluid with the oxidant in a stable, wide, and luminous flame. Alternatively, injectors may be used alone or with the refractory block to inject oxidant and fuel gases.
    Type: Grant
    Filed: December 14, 1998
    Date of Patent: June 13, 2000
    Assignees: American Air Liquide, Inc., L'Air Liquide, Societe Anonyme pour l'Etude et L'Exploitation des Procedes George Claude
    Inventor: Louis C. Philippe
  • Patent number: 6071115
    Abstract: A process and apparatus for combusting fuel which results in reduction of nitrogen oxides and carbon monoxides emissions. Fuel and primary air are preferably premixed and introduced into a combustion chamber. Secondary air is introduced through a plurality of secondary air ports, each preferably shaped as a slot, which are positioned about a venturi nozzle or flame holder disk mounted with respect to a combustion chamber wall. The secondary air flowing through the secondary air ports forms relatively high velocity and momentum secondary air jets that promote rapid mixing of the fuel and primary air mixture into the secondary air flow, such that a combustion flame is established at a partial periphery of the secondary air jets.
    Type: Grant
    Filed: September 5, 1997
    Date of Patent: June 6, 2000
    Assignee: Gas Research Institute
    Inventors: Philip C. Carbone, Karen R. Benedek, Stephan E. Schmidt, Charles E. Benson
  • Patent number: 6068468
    Abstract: A burner assembly having improved flame length and shape control is presented, which includes in exemplary embodiments at least one fuel fluid inlet and at least one oxidant fluid inlet, means for transporting the fuel fluid from the fuel inlet to a plurality of fuel outlets-, the fuel fluid leaving the fuel outlets in fuel streams that are injected into a combustion chamber, means for transporting the oxidant fluid from the oxidant inlets to at least one oxidant outlet, the oxidant fluid leaving the oxidant outlets in oxidant fluid streams that are injected into the combustion chamber, with the fuel and oxidant outlets being physically separated, and geometrically arranged in order to impart to the fuel fluid streams and the oxidant fluid streams angles and velocities that allow combustion of the fuel fluid with the oxidant in a stable, wide, and luminous flame. Alternatively, injectors may be used alone or with the refractory block to inject oxidant and fuel gases.
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: May 30, 2000
    Assignees: American Air Liquide, Inc., L'Air Liquide, Societe Anonyme Pour l'Etude et, l'Exploitation de Procedes Georges Claude
    Inventors: Louis C. Philippe, Harley A. Borders, Kenneth A. Mulderink, Pierre Bodelin, Patrick Recourt, Lahcen Ougarane, Remi Tsiava, Bernard Dubi, Laurent Rio
  • Patent number: 6050809
    Abstract: An immersion tube burner having stable ignition and flame over a wide range of firing rates. The burner includes a restriction orifice located between the fan and the burner nozzle for minimizing pulsations of air pressure fluctuations between the fan and nozzle. The orifice is sized so that the air velocity is greater through the orifice than at the nozzle so that any such pulsations are directed downstream of the nozzle rather than upstream, where they can affect the flame. The burner includes a burner nozzle having a cone shaped mixing plate. The angled shape of the plate re-circulates hot gases towards the base of the flame to thereby ensure more consistent ignition and combustion. The mixing plate further has holes arranged in primary and secondary zones. The holes of the primary zone are located within approximately five times the diameter of the fuel outlet ports so that the fuel exiting such ports has sufficient velocity to optimize mixing.
    Type: Grant
    Filed: September 23, 1997
    Date of Patent: April 18, 2000
    Assignee: Eclipse Combustion, Inc.
    Inventor: Matvey Fayerman
  • Patent number: 6045351
    Abstract: In a method of operating a burner of a heat generator, in which the burner essentially includes a swirl generator for a combustion-air flow, a mechanism for injecting at least one fuel into the combustion-air flow, and a number of transition passages for passing a flow formed in the swirl generator into a mixing tube arranged downstream of the transition passages, a predetermined quantity of a second fuel having a good ignition quality is injected into the reaction zone in order to stabilize the combustion in the combustion space.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: April 4, 2000
    Assignee: ABB Alstom Power (Switzerland) Ltd
    Inventors: Klaus Dobbeling, Christian Steinbach
  • Patent number: 6007326
    Abstract: A low NO.sub.x combustion process is carried out by reacting low concentrations of combustibles with low concentrations of oxygen. These low concentrations are obtained by injecting high velocity fuel and oxidant streams through port openings that are spatially separated.
    Type: Grant
    Filed: August 4, 1997
    Date of Patent: December 28, 1999
    Assignee: Praxair Technology, Inc.
    Inventors: Harry Monroe Ryan, III, Arthur Wellington Francis, Jr., Michael Francis Riley, Hisashi Kobayashi
  • Patent number: 5993191
    Abstract: A heater, especially a motor vehicle heater which can be operated independently of the engine, with a burner which is supplied with fuel and air via a binary nozzle (2), a combustion chamber (1), and a multistage compressor (3, 4) for compressing the air. The entire mass flow of air necessary for combustion in the combustion chamber (1) is sent to at least one first compressor stage (3) for compression to a first pressure level, and the air mass flow compressed in this way is divided into a first component flow supplied directly to the combustion chamber (1), and a second component flow which is compressed in at least one second compressor stage (4) to a second pressure level and sent to the binary nozzle (2) as the fuel atomization air mass flow.
    Type: Grant
    Filed: November 25, 1998
    Date of Patent: November 30, 1999
    Assignee: Webasto Thermosysteme GmbH
    Inventors: Ingrid Lanzl, Christian Hubbauer, Stefan Ullerich
  • Patent number: 5984667
    Abstract: A burner assembly having improved flame length and shape control is presented, which includes in exemplary embodiments at least one fuel fluid inlet and at least one oxidant fluid inlet, means for transporting the fuel fluid from the fuel inlet to a plurality of fuel outlets, the fuel fluid leaving the fuel outlets in fuel streams that are injected into a combustion chamber, means for transporting the oxidant fluid from the oxidant inlets to at least one oxidant outlet, the oxidant fluid leaving the oxidant outlets in oxidant fluid streams that are injected into the combustion chamber, with the fuel and oxidant outlets being physically separated, and geometrically arranged in order to impart to the fuel fluid streams and the oxidant fluid streams angles and velocities that allow combustion of the fuel fluid with the oxidant in a stable, wide, and luminous flame. Alternatively, injectors may be used alone or with the refractory block to inject oxidant and fuel gases.
    Type: Grant
    Filed: June 24, 1996
    Date of Patent: November 16, 1999
    Assignees: American Air Liquide, Inc., L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Louis C. Philippe, Harley A. Borders, Kenneth A. Mulderink, Pierre Bodelin, Patrick Recourt, Lahoen Ougarane, Remi Tsiava, Bernard Dubi, Laurent Rio
  • Patent number: 5975887
    Abstract: A burner apparatus having a burner tube in which is disposed a premixing tube having air communication with the air inlet end of the burner tube. An air diffuser bridges between the premixing tube and the burner tube. A baffle plate is supported by and seals across one end of the premixing tube and a plurality of gas/air mixture injection holes are dispersed in the premixing tube between the air diffuser plate and the baffle plate. A gas tube extends into the premixing tube and a plurality of gas holes are disposed along the gas tube in proximity to the discharge end of the gas tube so that air is premixed with gas and discharged from the gas holes to form a gas/air mixture which is passed from the gas/air mixture injection holes radially between the baffle plate and an air diffuser plate.
    Type: Grant
    Filed: January 23, 1998
    Date of Patent: November 2, 1999
    Assignee: Gordon-Piatt Energy Group, Inc.
    Inventors: Azfar Kamal, Danny Linn Christenson
  • Patent number: 5975886
    Abstract: A burner assembly having improved flame length and shape control is presented, which includes in exemplary embodiments at least one fuel fluid inlet and at least one oxidant fluid inlet, means for transporting the fuel fluid from the fuel inlet to a plurality of fuel outlets, the fuel fluid leaving the fuel outlets in fuel streams that are injected into a combustion chamber, means for transporting the oxidant fluid from the oxidant inlets to at least one oxidant outlet, the oxidant fluid leaving the oxidant outlets in oxidant fluid streams that are injected into the combustion chamber, with the fuel and oxidant outlets being physically separated, and geometrically arranged in order to impart to the fuel fluid streams and the oxidant fluid streams angles and velocities that allow combustion of the fuel fluid with the oxidant in a stable, wide, and luminous flame. Alternatively, injectors may be used alone or with the refractory block to inject oxidant and fuel gases.
    Type: Grant
    Filed: November 25, 1996
    Date of Patent: November 2, 1999
    Assignees: L'Air Liquide, Societe Anonyme Pour l'Etude et l'Exploitation des Procedes Georges Claude, American Air Liquide, Inc.
    Inventor: Louis C. Philippe
  • Patent number: 5961313
    Abstract: In a method of operating a swirl-stabilized burner operated with gaseous and/or liquid fuels (12, 16), in which combustion air (7) or a mixture of recycled flue gas (30) and fresh air (29), which mixture is formed by injector delivery, and fuel (12, 16) are intensively mixed by means of a swirl generator (37) and then burned, in the course of which a backflow zone (24), which stabilizes the flame, is formed, starting air (38), which has at least a radial velocity component, is injected during the starting action at the downstream end of the swirl generator (37) in such a way as to be directed from the margin of the burner into the center. The injection of the starting air (38) is switched off after the end of the starting action, so that the burner works in such a way as to be unaffected in normal operation. The invention improves the ignition conditions, increases the flame stabilization, and reduces the pollutant emissions when the burner is being started.
    Type: Grant
    Filed: March 2, 1998
    Date of Patent: October 5, 1999
    Assignee: ABB Research Ltd.
    Inventors: Jurgen Haumann, Hans Peter Knopfel, Thomas Sattelmayer
  • Patent number: 5944507
    Abstract: A liquid fuel burner is provided with a central fuel outlet having a generally divergent conical inner surface, formed of two contiguous divergent conical surfaces of different angles of divergence, and a plurality of oxygen outlets shaped and positioned for creating a converging, rotating stream of oxygen which intersects with any liquid fuel issuing from the fuel outlet. Such oxygen/fuel interaction results in two zones of combustion and a recirculation effect which assists in the complete or substantially complete combustion of undesirable exhaust gas components. The oxygen and fuel are preferably supplied such that their velocities are approximately equal at the point at which the two zones of combustion meet.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: August 31, 1999
    Assignee: The BOC Group plc
    Inventor: Christian J. Feldermann
  • Patent number: 5938422
    Abstract: A process for the combustive destruction of noxious substances from a gas stream in which the gas stream and added fuel gas as a mixture into a combustion zone that is surrounded by an exit surface of a foraminous gas burner. A fuel gas and air/oxygen mixture are simultaneously supplied to the foraminous gas burner to effect combustion at the exit surface. The resulting combustion product stream is discharged from the combustion zone. The oxygen is added to the gas stream and the fuel gas prior to the introduction of the mixture to the combustion zone and the oxygen/fuel gas mixture burns at the point of injection.
    Type: Grant
    Filed: April 16, 1997
    Date of Patent: August 17, 1999
    Assignee: The BOC Group plc
    Inventors: James Robert Smith, Andrew James Seeley
  • Patent number: 5934892
    Abstract: A process for combustion of a combustible material in which a primary combustible material is introduced into a combustion chamber having an upstream region and a downstream region, and ignited, forming a primary combustion zone. A secondary combustible material is partially combusted in a partial combustor, forming partial combustion products which are then injected into the combustion chamber downstream of the primary combustion zone, forming an oxygen deficient zone downstream of the primary combustion zone.
    Type: Grant
    Filed: August 6, 1998
    Date of Patent: August 10, 1999
    Assignee: Institute of Gas Technology
    Inventors: Iosif K. Rabovitser, Mark J. Khinkis, Michael J. Roberts
  • Patent number: 5931654
    Abstract: A system and method for protecting a nozzle that injects a high velocity main gas into a furnace or combustion zone. The nozzle is located in a passage recessed from the exit port opening of the passage which communicates with the combustion zone. Purge gas is passed into the passage upstream of the nozzle. The volume of the purge gas exceeds 50% of the total volume of the main gas and purge gas and the purge gas has a velocity of at least 100 ft/sec thereby preventing furnace gases from entering the passage and attacking the nozzle.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: August 3, 1999
    Assignee: Praxair Technology, Inc.
    Inventor: Ray Paul Chamberland