Catalyst Patents (Class 122/4D)
  • Patent number: 6159001
    Abstract: A superemissive combustion device of this invention comprises a porous distributive layer and an apparatus for delivering a fuel/oxidizer mixture to an upstream face of the porous distributive layer. A superemissive advanced emissive matrix in is disposed within an active flame zone downstream from the porous distributive layer. The emissive matrix is in the form of a three dimensional matrix of radiating bodies that is optically thin to electromagnetic radiation. The emissive matrix is either formed from or includes a coating of a superemissive material that is selected to emit photons within a predetermined wavelength range when thermally stimulated. The emitted photons are received by one or more photovoltaic cells disposed adjacent the matrix.
    Type: Grant
    Filed: October 9, 1998
    Date of Patent: December 12, 2000
    Assignee: Quantum Group, Inc.
    Inventors: Alexsandr S. Kushch, Mark K. Goldstein
  • Patent number: 6101983
    Abstract: A modified gas turbine system is provided that adapts an advanced pressurized fluidized bed combustor cycle for use with existing combustion turbine technology. To accommodate current combustion turbine technology, the air extracted from the compressor discharge is limited, e.g. to about 20% of the total. The additional air required for the APFBC cycle is provided by an auxiliary source of compressed air. The compressor discharge air that is not extracted is used for combustion of the fuel gas produced by the carbonizer and also provides internal cooling as required by conventional combustion turbine design. A separate expander turbine is used to recover energy from the vitiated air from the PFBC. Energy from the vitiated air may further be recovered by directing the expander exhaust to an HRSG.
    Type: Grant
    Filed: August 11, 1999
    Date of Patent: August 15, 2000
    Assignee: General Electric Co.
    Inventors: Ashok Kumar Anand, Ralph R. Boericke
  • Patent number: 6098553
    Abstract: An arrangement for converting a conventional oil boiler to a boiler with moist, granular and solid fuel, utilizes a fuel combustion gas dryer connected to the combustion gas line of the boiler, and a solid fuel combustion device to replace the oil burner. The combustion gas dryer is a so-called circulating fluidized bed (CFB) dryer together with a particle separator and a combustion gas center tap has been fitted into the oil boiler, through which center tap hot combustion gas has been set to be mixed with combustion gases of the normal outlet in the desired proportion in order to regulate the temperature of the drying gas of the dryer. The combustion devices may include a cyclone burner.
    Type: Grant
    Filed: March 29, 1999
    Date of Patent: August 8, 2000
    Assignee: Vapo Oy
    Inventors: Mauno Oksanen, Markku Miettinen, Markku Pyykkonen, Kari Pajunen
  • Patent number: 6095095
    Abstract: A CFB reactor or combustor having an impact type primary particle separator collects solids particles from a flow of flue gas/solids and returns the collected particles along an inclined or substantially horizontal planar floor to a bottom portion of the reactor or combustor for subsequent recirculation.
    Type: Grant
    Filed: December 7, 1998
    Date of Patent: August 1, 2000
    Assignee: The Bacock & Wilcox Company
    Inventors: Kiplin C. Alexander, Felix Belin, Mikhail Maryamchik, David J. Walker
  • Patent number: 6088990
    Abstract: A weldless connection system for U-beam particle separators is provided in which one end of each U-beam is provided with sides and a back that are separated from each other forming tabs. The tabs may be bent, or folded, about 90.degree. inward toward the channel formed by the U-beam. The back tab may be twice as long as the side tabs, and the extra half length of the tab can be folded about 180.degree. back at the back of the U-beam in a double thickness. Each tab has a hole therethrough. The double-length back tab has two holes; one hole is provided through each half. When the tabs are bent inward, the holes align. A bolt and washer placed through the aligned holes may be used to secure the tabs, and thus the U-beam, to a furnace roof structure. An alternate embodiment of the invention is provided in which only the sides of the U-beam form tabs which extend past the bottom of the U-beam.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: July 18, 2000
    Assignee: The Babcock & Wilcox Compnay
    Inventors: Michael Gold, David J. Walker, David E. James
  • Patent number: 6067943
    Abstract: The circulating fluidized bed boiler comprises a combustion hearth and a separator cyclone interconnected by a duct which extends along a longitudinal axis and which channels a flow of particles and gas containing nitrogen oxides. It also includes means for injecting into the flow a reagent for reducing nitrogen oxides. Said means comprises at least a first injection tube disposed in a setback of the top portion of the combustion hearth which extends over the duct so as to inject the reagent along the longitudinal axis of the duct in the same direction as the flow.
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: May 30, 2000
    Assignee: Alstom Energy Systems SA
    Inventors: Jean-Xavier Morin, Michel Vandycke, Corinne Beal
  • Patent number: 6058858
    Abstract: A circulating fluidized bed (CFB) reactor or combustor having an internal impact type primary particle separator which provides for internal return of all primary collected solids to a bottom portion of the reactor or combustor for subsequent recirculation without external and internal recycle conduits. The CFB reactor enclosure or furnace is provided with plural furnace outlets. This construction permits increased furnace depths and reduced furnace widths, resulting in a compact design.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: May 9, 2000
    Assignee: The Babcock & Wilcox Company
    Inventors: Felix Belin, David E. James, David J. Walker, Kiplin C. Alexander
  • Patent number: 6058857
    Abstract: A plurality of dispersive air pipes for combustion (11) containing a plurality of dispersive air holes and projecting in a cantilever fashion from the side walls (1b, 1c) in an oblique downward direction are provided in the lower portion of a combustion zone (2b) of a furnace main unit (1) which includes an ash discharge outlet (6) formed in the base portion of the furnace main unit, and an incombustible material discharge space (12) is formed between the ends of the dispersive air pipes for combustion (11). As a result, incombustible material accumulating on the dispersive air pipes for combustion (11) is guided to the incombustible material discharge space (12) and then discharged.
    Type: Grant
    Filed: March 23, 1998
    Date of Patent: May 9, 2000
    Assignee: Hitachi Zosen Corporation
    Inventors: Seiichi Nakai, Ryozo Shiji, Takeshi Matsui, Norihiro Aoki, Yoshimasa Miura, Yusuke Okada
  • Patent number: 6050226
    Abstract: An exhaust heat recovery boiler in which an exhaust gas discharged from a gas turbine into a boiler duct to recover a heat of the exhaust gas and ammonia is injected to and mixed with the exhaust gas to reduce nitrogen oxide contained in the exhaust gas, the exhaust heat recovery boiler comprising: a boiler duct of a horizontal installation type having an inner hollow portion along which an exhaust gas flows from an upstream side to a downstream side; a superheater; an evaporator; a denitration reactor; and an economizer, which are disposed inside the boiler duct in this order from the upstream side to the downstream side of the exhaust gas flow therein. A drum is disposed outside the boiler duct and connected to the evaporator and a downcomer pipe extending from the drum into the boiler duct.
    Type: Grant
    Filed: October 7, 1998
    Date of Patent: April 18, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Shimada, Norihide Egami, Takayuki Nagashima
  • Patent number: 6039008
    Abstract: There is provided a circulating fluidized bed steam generator (CFB) having an improved structural support system and an improved combined hot solids-gas separator for separating gas and solids from a combined gas-solids stream. The combined hot solids-gas separator is in the form of a cyclone assembly having a plurality of wall portions forming a separation chamber and an inlet for passage of a combined gas-solids stream into the separation chamber. The lowermost extent of the inlet forms a threshold over which the combined gas-solids stream flows in entering the separation chamber. The separation chamber is operable to separate the combined gas-solids stream into a predominantly gas exit stream and a predominantly solids exit stream in a manner by which separated out solids to be discharged from the separation chamber via the predominantly solids exit stream are collected within the separation chamber at a location lower than the inlet.
    Type: Grant
    Filed: February 1, 1999
    Date of Patent: March 21, 2000
    Assignee: Combustion Engineering, Inc.
    Inventors: David K. Anderson, John H. Chiu, Steven F. McNary, Nicole M. Phyfe, David G. Turek, Donald G. Mylchreest
  • Patent number: 6029612
    Abstract: A fluidized bed reactor including in its lower part a furnace section having a bed of fluidized solid particles, the furnace section being delimited by side walls such as external side walls and/or partition walls and a bottom grid, and a supplying device for introducing gas into the furnace section at a level above the bottom grid, the supplying device including a gas source chamber, an opening in at least one of the side walls at a level above the bottom grid, and a conduit having a first end connected to the opening and a second end connected to the gas source chamber. The conduit includes a solid flow seal preventing solid particles from flowing backwards from the furnace section into the conduit in a manner preventing or noticeably decreasing introduction of gas from the gas source chamber to the furnace section.
    Type: Grant
    Filed: July 7, 1997
    Date of Patent: February 29, 2000
    Assignee: Foster Wheeler Energia Oy
    Inventors: Donald L. Wietzke, Neil R. Raskin, Scott Darling
  • Patent number: 6021743
    Abstract: A steam generator achieves an especially high efficiency when biomass is used as a fuel. The steam generator contains a first combustion chamber for generating a gaseous working medium by burning a first fuel and a second combustion chamber for burning a second fuel. The second combustion chamber is connected downstream of the first combustion chamber in flow direction of the working medium. Bituminous coal may be fed as the first fuel to the first combustion chamber and/or biomass, in particular straw, may be fed as the second fuel to the second combustion chamber. The working medium generated in the first combustion chamber during operation of the steam generator serves as combustion air in the second combustion chamber.
    Type: Grant
    Filed: February 23, 1998
    Date of Patent: February 8, 2000
    Assignee: Siemens Aktiengesellschaft
    Inventor: Gunter Bauer
  • Patent number: 6019068
    Abstract: An apparatus for reducing the concentration of nitrogen oxides in flue gases produced in a furnace of a combustion unit includes a device for maintaining combustion reactions in the furnace, the combustion reactions resulting in the production of hot gases containing nitrogen oxides, the hot gases flowing mainly upwardly within the furnace, internal heat transfer surfaces within the furnace for recovering heat from the mainly upward flow of hot gases, an introducer for introducing nitrogen oxides reducing agent into the upward flow of hot gases in the furnace, for reducing the concentration of nitrogen oxides in the hot gases, wherein the introducer is integrally connected to the internal heat transfer surfaces, for keeping the temperature of the reducing agent at a sufficiently low temperature level upon introduction thereof into the furnace, and for efficiently mixing the reducing agent with the upward flow of hot gases, and a discharge for discharging flue gases from the furnace.
    Type: Grant
    Filed: July 17, 1998
    Date of Patent: February 1, 2000
    Assignee: Foster Wheeler Energia Oy
    Inventors: York Tsuo, Carl Johnk, Yam Lee
  • Patent number: 6016863
    Abstract: Heat exchanger consisting of a reservoir with upwardly directed tubes through which flow a liquid to be heated and fluidized bed particles for internally cleaning the tubes. Connected to the reservoir is an external downcomer (5) for collecting fluidized bed particles coming from the top box of the reservoir and to be transported back to the bottom box (7) of the reservoir. The connecting line (4, 2, 1, 3, 6) between downcomer (5) and bottom box (7) is designed as two sections (2, 3) with an expansion bellows (1) arranged between them. The bottom section (3) is connected via two or more connecting stubs (6A, 6B) with the bottom box (7) for the uniform distribution of the flow of fluidized bed particles.
    Type: Grant
    Filed: March 11, 1998
    Date of Patent: January 25, 2000
    Assignee: Klarex Beheer B.V.
    Inventor: Dick Gerrit Klaren
  • Patent number: 6003475
    Abstract: A power plant which combusts fossil fuel and biomaterial or waste includes a large boiler plant having at least one device for the combustion of fossil fuel. At least one additional combustion device is connected to the large boiler plant via at least one connection channel. The additional combustion device includes a grate hearth for the combustion of biomaterial or waste. The additional combustion device includes at least one heat exchanger device which is integrated into the water/steam circuit of the large boiler plant.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: December 21, 1999
    Assignee: Alstom Energy Systems GmbH
    Inventors: Birgit Elsner, Hellmuth Bruggemann, Uwe Krogmann, Tino-Martin Marling, Gerhard Schroth, Walter Vogt
  • Patent number: 6003476
    Abstract: A boiler comprising a circulating fluidized bed hearth, a separator member for separating flue gas and solids extracted from the hearth, an external dense fluidized bed between the solids outlet of the separator member and the base of the hearth, the external bed containing a first heat exchanger in which a coolant fluid to be evaporated circulates. The outlet of the first heat exchanger is connected to a second heat exchanger placed in the hearth.
    Type: Grant
    Filed: August 17, 1998
    Date of Patent: December 21, 1999
    Assignee: Gec Alsthom Stein Industrie
    Inventors: Jean-Claude Semedard, Pierre Gauville, Christian Enault
  • Patent number: 5988115
    Abstract: A system and method of injecting an ammonia or urea reactant into a flue gas stream in a steam generating power plant that utilizes Selective Catalytic Reduction (SCR) to lower NO.sub.x emissions and more specifically the injection of the reactant in such a manner that a more uniform mixing of the reactant with the flue gas stream is achieved more rapidly thereby increasing the efficiency of the catalytic reduction process and further a method of increasing the amount of reaction that takes place between the reactant/flue gas mixture and the catalytic material.
    Type: Grant
    Filed: August 11, 1998
    Date of Patent: November 23, 1999
    Inventors: David K. Anderson, Michael J. Rini
  • Patent number: 5983840
    Abstract: The invention relates to a steam generator, which consists of a combustion chamber (1), a radiation part (2) and a convection part (3) and which has at least two vertical gas passes (4, 5) following the combustion chamber (1), in each case with a 180.degree. deflection of the flue gas (12), the combustion chamber (1) and the gas pass (4) being separated from one another by means of a first partition (14) and the two gas passes (4, 5) being separated from one another by means of a second partition (6). It is defined in that the second partition (6) is designed, at its lower end, in such a way that the passage area for the flue gas (12) from the vertical pass (4) with downward flow to the vertical pass (5) with upward flow has a variable value over the width, the passage area being smaller in the middle than on the outside. The secondary flow occurring during deflection is thereby reinforced, in the wall region the vortices of said secondary flow rotating opposite to the direction of the main flow deflection.
    Type: Grant
    Filed: September 16, 1998
    Date of Patent: November 16, 1999
    Assignee: Asea Brown Boveri AG
    Inventors: Oliver Riccius, Georg Ziegler
  • Patent number: 5979341
    Abstract: A fluidized-bed thermal reaction apparatus burns or gasifies combustible matter containing incombustible components, so that deposition of incombustible components in a fluidized-bed furnace is prevented, and incombustible components are smoothly removed, thereby efficiently burning or gasifying the combustible matter. A weak diffusion plate, a strong diffusion plate, and an auxiliary diffusion plate, each have a large number of fluidizing gas feed holes. An incombustible component outlet is disposed between the auxiliary diffusion plate and the strong diffusion plate. A part of fluidizing gas is supplied from the incombustible component outlet, or the incombustible component outlet is provided to open horizontally. Thus, a continuous fluidized bed circulating stream is formed in the furnace bottom. The weak and auxiliary diffusion plates each has a downwardly inclined surface extending toward the incombustible component outlet.
    Type: Grant
    Filed: June 17, 1998
    Date of Patent: November 9, 1999
    Assignee: Ebara Corporation
    Inventors: Shuichi Nagato, Takahiro Oshita
  • Patent number: 5979367
    Abstract: A dense fluidized bed exchanger includes a casing the vertical longitudinal walls of which consist of tubes conveying a heat-conducting fluid, the casing being divided lengthwise into chambers separated from each other by a baffle consisting of a wall consisting of tubes conveying a heat-conducting fluid. The vertical longitudinal walls consist of horizontal tubes and the baffle extends from the bottom wall of the casing to a height less than that of the latter and consists of superposed hairpin-shape transverse extensions of tubes of each of the vertical longitudinal walls disposed perpendicular to the tubes and extending to the opposite vertical longitudinal wall.
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: November 9, 1999
    Assignee: GEC Alsthom Stein Industrie
    Inventors: Jean Aubry, Djamel Daoud, Alain Quaranta
  • Patent number: 5967098
    Abstract: A fluidized bed combustion system is disclosed and in particular a fluidized bed combustion system particularly well suited for the combustion of oil shale, generating steam thereby. The fluidized bed combustion system includes a furnace volume having a multi-chambered upper segment thereof, a deentrainment zone, a fluidized bed having a plurality of isolatable segments thereof, a fluidized bed ash cooler having a plurality of isolatable segments thereof wherein the fluidized bed ash cooler is in fluid communication with the furnace volume, a fuel supply means in fluid communication with the furnace volume for delivering oil shale thereto for combustion therein, a backpass volume defined by a plurality of backpass wall tubes integral to a thermodynamic steam cycle and in fluid flow relation with the furnace volume and a plurality of circulatory fluid flow paths integral to a thermodynamic steam cycle and operative to conduct the flow of steam or water therethrough.
    Type: Grant
    Filed: June 22, 1998
    Date of Patent: October 19, 1999
    Inventors: Michael C. Tanca, Mark S. Zak
  • Patent number: 5957066
    Abstract: In a fluidized-bed thermal reaction apparatus for burning or gasifying combustible matter containing incombustible components, deposition of incombustible components in a fluidized-bed furnace is prevented, and incombustible components are smoothly removed, thereby efficiently burning or gasifying combustible matter. The fluidized-bed thermal reaction apparatus has a weak diffusion plate, a strong diffusion plate, and an auxiliary diffusion plate, each having a large number of fluidizing gas feed holes, and an incombustible component outlet disposed between the auxiliary diffusion plate and the strong diffusion plate. A part of fluidizing gas is supplied from the incombustible component outlet, or the incombustible component outlet is provided to open horizontally. Thus, a continuous fluidized bed circulating stream is formed in the furnace bottom. The weak and auxiliary diffusion plates each has a downwardly inclined surface extending toward the incombustible component outlet.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: September 28, 1999
    Assignee: Ebara Corporation
    Inventors: Shuichi Nagato, Takahiro Oshita
  • Patent number: 5951277
    Abstract: A shield in the form of a "cast refrac" (S.U.B.S.) for a diffuser port in a circulating fluidized bed to deflect eroding particulates away from the port. The S.U.B.S. includes an upper portion with a tear-drop shape, a lower portion, and side intermediate portions to surround the port, and an attached insert to be received by or around the port.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: September 14, 1999
    Assignee: The Robert L. Parham Trust
    Inventor: Robert L. Parham
  • Patent number: 5918569
    Abstract: An apparatus and method for processing materials in a batchwise or continuous fluidised bed, such as a drier, in which the fluidised bed is subdivided into a plurality of smaller areas, to each of which two separately controlled gas flows are provided. The first lower gas flow is provided to the bed preferably all of the time, and is sufficient at least to maintain the bed in an expanded state. The second higher gas flow is provided to each separate area of the bed in sequence by means of a rotary valve arrangement, and is high enough to induce fluidisation in the bed, but not high enough to induce significant solids loss by entrainment in the offtake gas. The higher flow sequence can be chosen to provide almost any desired sequence to the separate parts of the bed. The sequence can be chosen to induce a travelling wave within the bed which can be across or along the bed, and can be skewed relative to the sides of the bed.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: July 6, 1999
    Assignee: Her Majesty the Queen in right of Canada, as represented by the Minister of Natural Resources
    Inventors: Tadeusz Kudra, Zbigniew Gawrzynski, Ryszard Glaser
  • Patent number: 5913287
    Abstract: Semi-permeable screens are installed in a pulverized coal burning boiler and rotatably driven by a high speed rotatable shaft. A first one of the screens is located above the main combustion zone of the boiler and a second one of the screens is located directly under the burnout zone of the boiler. The underside of the first rotating screen repels the larger and slower burning fuel particles that escape from the main combustion zone so that they are recycled for a complete burn-out. The smaller glowing particles suspended in the combustion gases pass through the first rotating screen and are micronized by the comminution effected by the spiral vortexes generated above this first screen. The second rotating screen positioned under the burnout zone provides for mixing and comminution of the gases and burning coal particles respectively. The vortexes generated by the screens homogenize the heat distribution in the upwardly moving stream of gas and solid particulates.
    Type: Grant
    Filed: August 26, 1998
    Date of Patent: June 22, 1999
    Inventor: Ernest Csendes
  • Patent number: 5911201
    Abstract: A continuously operated boiler heated with a pressurized circulating fluidized bed firing consists of a fluidized bed burner chamber (1) and one or more cyclones (5) connected in series after the fluidized bed burner chamber (1) and on the flue gas side. A fluidized bed cooler (12) is connected in series after each cyclone (5) which cooler is connected by way of a dip pot (8) with the solids output of the cyclone on one hand and with the fluidized bed burner chamber 91) on the other hand. A return conduit (10) is connected with the dip pot (8) which opens into the fluidized bed burner chamber 91). Pressure vessels (18, 19) house the fluidized bed burner chamber (1), the cyclone (5) and the fluidized bed cooler 912). The fluidized bed cooler (12), the cyclone (5) and the dip pot (8) are thereby combined into a unite which is housed in the common pressure vessel (19).
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: June 15, 1999
    Assignee: LLB Lurgi Lentjes Babcock Energietechnik GmbH
    Inventor: Leonhard Eickenberg
  • Patent number: 5911956
    Abstract: A method of reducing the nitrogen oxide level in the flue gases issuing from combustion units by introduction of reducing agents into contact with gases containing nitrogen oxides in first and second reducing stages, is provided. The first reducing stage is a non-catalytic stage (e.g. at temperatures over 800.degree. C.), while the second stage is a catalytic stage (e.g. at temperatures of about 300-400.degree. C.). A steam generation boiler with improved nitrogen reduction facilities is also provided. The amount of nitrogen oxides in the hot gases is reduced in the combination of the first and second reducing stages while producing steam in a steam generation boiler system, thus resulting in gases essentially free from nitrogen oxides while eliminating the possibility of NH.sub.3 (or other reducing agent) slip in the exhausted flue gases. Heat transfers in a convection section as used to establish stabilized temperature conditions for catalytic reduction.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: June 15, 1999
    Assignee: Foster Wheeler Energia Oy
    Inventors: Charles Viel Lamare, Matti Hiltunen, Yam Lee
  • Patent number: 5907910
    Abstract: A method has been found to improve the efficiency of a cyclone system for a fluidized bed. The typical plurality of cyclones arranged in series in communication with the fluidized bed is replaced by a plurality of similarly-sized cyclones arranged in parallel, so that the residence time in each of the cyclones is greater than it was in the original system, thereby greatly improving the recovery of particulate material while greatly reducing the energy consumption of the system.
    Type: Grant
    Filed: April 24, 1997
    Date of Patent: June 1, 1999
    Assignee: Fisher-Klosterman, Inc.
    Inventor: William L. Heumann
  • Patent number: 5904119
    Abstract: A fluidized bed reactor includes a plurality of nozzles for introducing a fluidizing gas wherein at least some of the nozzles are provided with a plate proximate to the nozzle inlet which redirects the flow of the fluidizing gas to the nozzles. By providing a plate at the inlet of the nozzles the following is accomplished. Even flow distribution of the fluidizing gas through the nozzle is achieved. The pressure drop through the nozzle remains relatively high thus insuring good fluidizing gas acceleration which eliminates the adherence of the fines to the interior surface of the nozzle.
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: May 18, 1999
    Assignee: Brifer International Ltd.
    Inventor: Adersido Gomez
  • Patent number: 5899172
    Abstract: A separated overfire air injection system particularly suited for use in a fossil fuel-fired steam generating power plant and more specifically to a sixpoint separated overfire air tangential firing system employed in such power plants, particularly those embodying dual-chambered furnaces. A method of operating such a fossil fuel-fired steam generating power plant equipped with the sixpoint separated overfire air injection system of the present invention is also disclosed. The separated overfire injection system in accordance with the present invention includes six SOFA windboxes strategically located about the perimeter of the dual-chambered furnace volume so as to be operative to inject separated overfire air into the furnace volume in such a manner as to engage a fireball symmetrically tangential to a circle.
    Type: Grant
    Filed: April 14, 1997
    Date of Patent: May 4, 1999
    Assignee: Combustion Engineering, Inc.
    Inventors: John V. Dallen, Steven B. Fothergill
  • Patent number: 5893340
    Abstract: A water tube wall or heat transfer surface for use in a circulating fluidized bed combustor or reactor having reduced erosion at a transition between a protective refractory material and the upper wall.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: April 13, 1999
    Assignee: The Babcock & Wilcox Company
    Inventors: Felix Belin, David J. Walker
  • Patent number: 5878700
    Abstract: An integrated reburn system for a cyclone-fired boiler has a reburn fuel feed nozzle through a cyclone burner into the cyclone barrel, or furnace, at a region of low-velocity fuel and air movement. The reburn fuel is injected at high velocity and mostly does not mix with the combustion fuels and gases within the cyclone barrel. The reburn fuel passes through the re-entrant throat of the cyclone into the main furnace, where it forms a reburn zone having a reducing atmosphere in which the reburn fuel reacts with combustion gases from the main combustion zone to convert NO.sub.x to N.sub.2, thereby reducing the amount of NO.sub.x emissions produced by the furnace.
    Type: Grant
    Filed: November 21, 1997
    Date of Patent: March 9, 1999
    Assignees: The Babcock & Wilcox Company, McDermott Technology, Inc.
    Inventors: Hamid Farzan, Gerald J. Maringo
  • Patent number: 5875722
    Abstract: A system and method for purification of combustion gases cools the combustion gases to an optimal oxidation temperature, oxidizes the combustion gases, injects water or uses natural moisture content to form acid aerosols, neutralizes the acid aerosols with an alkaline solution, and then filters the acid aerosol, alkaline solution and water from the combustion gases. The purified gas stream is then exhausted from the system. Oxidation can be provided in stages to obtain optimal oxidation of different combustion gas components with different optimal oxidation temperature ranges. When used in a thermal power plant, the cooling of exhaust gases can be accomplished by regenerative preheating of combustion air, boiler feedwater or combustion fuel, and the clean exhaust gas can be cooled below the conventional exhaust stack temperature range, thus enhancing power plant efficiency.
    Type: Grant
    Filed: September 9, 1996
    Date of Patent: March 2, 1999
    Assignee: Dasibi, Inc.
    Inventors: Albert E. Gosselin, Jr., Edward R. Bate, Jr., Dale F. Johnson
  • Patent number: 5868082
    Abstract: A dual fuel gasification-combustion system (44)with multi-stage fluidised bed gasifier (32)for complete carbon conversion of the input fuel using single or combineable oxidants and sulphur sorbents to produce a clean fuel gas and combustion gas at any pressure for use with boilers gas turbines,or, combined cycle gas-steam turbines.The application (44) for combined cycle power includes a multi-stage gasifier (32)with design number of stages to maximise carbon conversion of input liquid or solid fuels being connected to a gas turbine (53)via gas cleaners (45),(47)and afterburner (46)to produce a clean combustion gas entering the gas turbine. The system has coolant conduits (6) in the gasifier and in the afterburner at (50) and generated steam from the boiler (54) for the steam turbine (51).
    Type: Grant
    Filed: June 19, 1995
    Date of Patent: February 9, 1999
    Inventor: John Hunter
  • Patent number: 5851498
    Abstract: A catalytic heater includes a catalyst, for the combustion of a gaseous hydrocarbon in air, supported on a catalyst support. Fuel diffuses into the catalyst support from one (proximal) side. Air diffuses into the catalyst support from the other (distal) side. The catalytic combustion of the fuel heats the catalyst support. The resulting infrared radiation from the distal side of the catalyst support is directed at an object to be heated, for example the fluid chamber of a boiler. A modular boiler includes several catalytic heaters, with the distal sides of their catalyst supports facing a chamber wherethrough a fluid such as water is conducted and heated by the infrared radiation from the heaters.
    Type: Grant
    Filed: December 2, 1996
    Date of Patent: December 22, 1998
    Assignee: Catalytic Systems Technologies, Ltd.
    Inventors: Vladimir Rozenshtein, Yehuda Heimlich
  • Patent number: 5836257
    Abstract: A circulating fluidized bed processor has a processor enclosure at least partially defined by a front wall and a rear wall spaced away from the front wall. A bottom wall is connected between the front and rear walls and a mechanism is provided for supplying primary air through the bottom wall for fluidizing a circulating bed in the enclosure. Another mechanism is provided for recirculating the bed from a top of the enclosure back to the enclosure. One or more secondary air plenum(s) are provided in the enclosure between the front and rear walls for supplying secondary air into the fluidized bed, above the bottom wall, so that secondary air reaches deep into the enclosure. The plenum(s) are formed of a waterwall which has a plurality of openings therein to allow communication of gases and solids therethrough from one side of the waterwall to the other.
    Type: Grant
    Filed: December 3, 1996
    Date of Patent: November 17, 1998
    Assignee: McDermott Technology, Inc.
    Inventors: Felix Belin, David J. Walker
  • Patent number: 5822991
    Abstract: A method for exercising control over the final predefined superheat outlet steam temperature and for exercising control over the final predefined reheat outlet steam temperature from a circulating fluidized bed steam generator having a furnace volume embodying at least superheat surface, a multichambered backpass volume embodying at least superheat surface within one chamber of the multichambered backpass volume and at least reheat surface within another one of the multichambered backpass volume, a first circulatory fluid flow path operative as an evaporative steam loop, and a second circulatory fluid flow path operative as a superheat steam-reheat steam loop and including a saturated steam segment, a superheat steam segment, a reheat steam segment and an economizer segment.
    Type: Grant
    Filed: February 14, 1997
    Date of Patent: October 20, 1998
    Assignee: Combustion Engineering, Inc.
    Inventors: Stephen A. Pierzchala, Bruce W. Wilhelm
  • Patent number: 5809912
    Abstract: A heat exchanger and a fluidized bed combustion system and method utilizing same in which the heat exchanger includes a plurality of stacked sections. The sections include an inlet section for receiving the particles and a plurality of stacked sections and are arranged in such a manner that the particles are introduced into an upper level of the sections and pass through these sections to a lower level of sections before returning to the furnace. A portion of the stacked sections contain heat exchange surfaces for removing heat from the particles, and a multi-sectioned outlet compartment is provided to receive the separated particles from the heat exchange sections and directly from the inlet section and pass the particles back to the furnace.
    Type: Grant
    Filed: June 11, 1996
    Date of Patent: September 22, 1998
    Assignee: Foster Wheeler Energy, Inc.
    Inventors: Arthur Magne Hansen, Stephen John Goidich
  • Patent number: 5809940
    Abstract: An improved CFB reactor or combustor arrangement has at least a first and a second group of impact type particle separators or U-beams with cooling surfaces located adjacent and immediately upstream of the second group of U-beams which serve to cool flue gas/solids flowing through the CFB before it reaches the second group of U-beams. By reducing the gas temperature in the vicinity of and entering the second group of U-beams, the U-beams can be made of less expensive materials and are thus less expensive to produce and maintain. The heat absorbed by the local cooling surfaces can be applied to heat a working fluid supplied to a turbine or other process.
    Type: Grant
    Filed: May 23, 1997
    Date of Patent: September 22, 1998
    Assignee: The Babcock & Wilcox Company
    Inventors: David E. James, David J. Walker, Felix Belin
  • Patent number: 5797334
    Abstract: A fluidized bed boiler bottom with an ash cooling and removal system has a water-cooled tube panel floor with fluidization bubble caps above a windbox, and a structural support and at least one hopper, each of the at least one hoppers with a bed ash cooler region and drain control system positioned beneath the tube panel floor. The hoppers are formed from cooled enclosure tubes and have sloped upper walls and lower troughs having vertical walls. Standpipes are provided through the tube panel floor down into the troughs at the bottoms of the hoppers. The standpipes may be arranged in an H-pattern in the tube panel floor and subsequently channel several flowpaths together into fewer standpipes closer to the troughs. Solids flow through the standpipes is controlled by operation of fluidizing nozzles located underneath the standpipes. Pulsing the flow of air through the fluidizing nozzles prevents or allows solids to flow through the standpipe from the bed.
    Type: Grant
    Filed: February 12, 1997
    Date of Patent: August 25, 1998
    Assignee: The Babcock & Wilcox Company
    Inventor: Paul S. Weitzel
  • Patent number: 5784975
    Abstract: A control scheme for large circulating fluidized bed steam generators (CFB) wherein direct control is effected therewith over the temperature of the large circulating fluidized bed steam generators (CFB) and wherein independent control is effected therewith over the final superheat steam temperature of the large circulating fluidized bed steam generators (CFB) as well as over the final reheat steam temperature of the large circulating fluidized bed steam generators (CFB).
    Type: Grant
    Filed: December 23, 1996
    Date of Patent: July 28, 1998
    Assignee: Combustion Engineering, Inc.
    Inventor: Michael C. Tanca
  • Patent number: 5776416
    Abstract: A fluidized bed reactor comprises a reaction column, gas inflow means for flowing a gas upwardly from the lower end of the reaction column, particle feed means for feeding particles to a lower part of the reaction column, and a cyclone. The cyclone includes a cyclone body having an inlet, a gas outlet and a particle drop port, and a particle discharge pipe having an upper end communicating with the particle drop port of the cyclone body. A main fluidized bed of particles fed by the particle feed means is formed at the lower part of the reaction column, and a gas, which is to be discharged from the reaction column and which is accompanied by particles, is introduced from the inlet into the cyclone body and discharged from the gas outlet of the cyclone body. The particle discharge pipe of the cyclone communicates with the lower part of the reaction column.
    Type: Grant
    Filed: November 13, 1996
    Date of Patent: July 7, 1998
    Assignee: Tokuyama Corporation
    Inventor: Hiroyuki Oda
  • Patent number: 5775266
    Abstract: In a steam generator (1) having, downstream of the fire-box (7), a radiant part and, subsequent thereto, a convective part, the latter essentially comprising, connected in series on the flue-gas side, contact heat exchanger (18), superheater (9) and economizer (2), the steam generator (1) being used in a circuit for the direct selective catalytic reduction (SCR process) of the nitrogen oxides in the flue gas (19), the economizer (2) consists of two parts.
    Type: Grant
    Filed: March 26, 1996
    Date of Patent: July 7, 1998
    Assignee: Asea Brown Boveri AG
    Inventor: Georg Ziegler
  • Patent number: 5771844
    Abstract: A cyclone separator adapted for attachment to the upper outlet end of a fluidized bed reactor such as an atmospheric (ACFB) or pressurized fluidized bed combustor (PFBC) has its gas flow capacity increased while maintaining high inlet gas flow velocity and particle separation efficiency. The cyclone inlet flow passageway has aspect ratio h/w increased to at least 4/1 and preferably to the range of 5/1 to 10/1. Also, the inlet passage inner wall is tapered or curved so that the inlet opening area exceeds that of the outlet opening adjacent the cyclone barrel. The cyclone outlet vortex tube lower portion has a truncated cone shape attached to a cylindrical-shaped vortex tube upper portion. The cyclone separator can be formed from multiple parallel tubes each having longitudinal fins for carrying a cooling fluid such as water or steam, and having a refractory material covering the tubes and fins.
    Type: Grant
    Filed: April 4, 1996
    Date of Patent: June 30, 1998
    Assignee: Foster Wheeler Development Corp.
    Inventor: David H. Dietz
  • Patent number: 5759495
    Abstract: A method and apparatus for treating hot process gases produced in high temperature processes in a circulating fluidized bed reactor. The reactor (10) includes a mixing chamber (12), a particle separator (16) and a return duct (18) for returning the circulating mass from the particle separator to the mixing chamber. The return opening (24) of the return duct is so arranged that the flow of solids entering the mixing chamber via the opening is directed substantially downwardly. The inlet (22) for hot process gas is so arranged as to allow the hot process gas to flow into the mixing chamber as a substantially upwardly directed solids flow so that the solids flow comes into contact with the gas flow.
    Type: Grant
    Filed: July 18, 1996
    Date of Patent: June 2, 1998
    Assignees: A. Ahlstrom Corporation, Hismelt Corporation PTY. Limited
    Inventor: Timo Hyppanen
  • Patent number: 5755187
    Abstract: The invention relates to a boiler for the production of steam, the boiler having a maximum capacity of 100 ton/hr or more and comprising a furnace having a substantially constant rectangular cross-section and a back pass with a substantially constant rectangular cross-section. The furnace and the back pass are mounted close to each other and means are provided for superheating the steam. The steam superheating means are positioned within the back pass, so that no superheater is positioned within the furnace.
    Type: Grant
    Filed: April 27, 1995
    Date of Patent: May 26, 1998
    Assignee: Gotaverken Energy AB
    Inventors: Lennart Nordenberg, Ola Herstad
  • Patent number: 5743197
    Abstract: A grate assembly for a fluidized bed boiler comprises a number of parallel sparge pipes or the like extending side-by-side in a substantially horizontal plane and provided with elements for supplying fluidizing air from within the sparge pipes or the like into a combustion chamber located above the grate assembly. The discharge of some of the fluidized bed materials is effected through an aperture system formed between the adjacent sparge pipes into a receiver unit fitted below the grate assembly. The sparge pipes are provided with a cooling medium circulation by means of a duct assembly.
    Type: Grant
    Filed: December 9, 1996
    Date of Patent: April 28, 1998
    Assignee: Tampella Power Oy
    Inventors: Jouni Kinni, Jukka Louhimo, Pentti Janka, Kari Haverinen
  • Patent number: 5725614
    Abstract: A combustion apparatus in which combustible matter, e.g., waste matter, coal, etc., is gasified to produce a combustible gas containing a sufficiently large amount of combustible component to melt ash by its own heat. A fluidized-bed furnace has an approximately circular horizontal cross-sectional configuration. A moving bed, in which a fluidized medium settles and diffuses, is formed in the central portion of the furnace, and a fluidized bed, in which the fluidized medium is actively fluidized, is formed in a peripheral portion in the furnace. The fluidized medium is turned over to the upper part of the moving bed from the upper part of the fluidized bed, thus circulating through the two beds. Combustible matter is cast into the upper part of the moving bed and gasified to form a combustible gas while circulating, together with the fluidized medium.
    Type: Grant
    Filed: October 24, 1995
    Date of Patent: March 10, 1998
    Assignee: Ebara Corporation
    Inventors: Yoshio Hirayama, Takahiro Oshita, Chikashi Tame, Shuichi Nagato, Tetsuhisa Hirose, Norihisa Miyoshi, Seiichiro Toyoda, Shugo Hosoda, Shosaku Fujinami, Kazuo Takano
  • Patent number: 5706884
    Abstract: An apparatus for carrying out a physical and/or a chemical process, such as a heat exchanger, a reservoir, in which a fluidized bed of granular material is present, is provided with upwardly directed tubes to a top box. Particles circulate up through the tubes, to a downcomer arranged outside the reservoir. The top of the downcomer is connected to a separating device, and the bottom of the downcomer opens into a collecting reservoir. The collecting reservoir communicates via a valve with the fluidized bed in the reservoir.
    Type: Grant
    Filed: January 30, 1996
    Date of Patent: January 13, 1998
    Assignee: Bronswerk Heat Transfer B.V.
    Inventor: Dick Gerritt Klaren
  • Patent number: 5687658
    Abstract: A method of burning coal with less than 10% volatiles in a burner supported by air. The coal is pulverized in a pulverizer and supplied to the burner mixed with a vehicle in the form of air. The object is more reliable ignition. The coal is separated from the air before it enters the burner and is combined into a new mixture with heated air. The second mixture is forwarded at a higher temperature and with a lower level of coal. The coal is separated from the second mixture and combined into a third mixture with heated air. The third mixture is forwarded at a higher temperature and with a higher level of coal.
    Type: Grant
    Filed: June 12, 1996
    Date of Patent: November 18, 1997
    Assignee: Babcock Lentjes Kraftwerstechnik GmbH
    Inventors: Michael Streffing, Alfons Leisse