Catalyst Patents (Class 122/4D)
  • Patent number: 5406914
    Abstract: A circulating fluidized bed (CFB) system, and a method of operation thereof, provide a heat transfer zone containing primarily clean fluidizing gas providing advantageous conditions for superheating, while providing a large enough flow of solid material in the heat exchange chamber during both high and low load conditions to achieve the desired heat transfer capacity. The heat exchange chamber is provided near the bottom of a return duct connected between the particle separator and combustion chamber of the CFB, with a common wall separating the combustion and heat exchange chambers. Particles are reintroduced into the combustion chamber through a solid particle inlet (plurality of narrow, substantially horizontal, elongated, vertically stacked slots) in the common wall, and particles may pass directly from the combustion chamber into the heat exchange chamber through a passage in the common wall above the solid particle inlet.
    Type: Grant
    Filed: October 5, 1993
    Date of Patent: April 18, 1995
    Assignee: A. Ahlstrom Corporation
    Inventor: Timo Hyppanen
  • Patent number: 5401130
    Abstract: A fluidized bed combustion system (10) particularly suited for use to effect the incineration, i.e., combustion, therewith of wood waste/sludge mixtures that have high moisture and ash content which makes them difficult to burn. The fluidized bed combustion system (10) includes a fluidized bed combustor (12) embodying a fluidized bed (24) composed of bed solids. Air is injected into the fluidized bed (24) through an air distributor (28) to establish a first controlled fluidizing velocity zone and a second controlled fluidizing velocity zone therewithin. Material (42b) is introduced into the fluidized bed combustor (12) above the second controlled fluidizing velocity zone. Bed solids are projected from the first controlled fluidizing velocity zone to the second controlled fluidizing velocity zone whereupon the bed solids rain down upon the material (42b) and effect a covering thereof. The material (42b) is then dried and thereafter combusted.
    Type: Grant
    Filed: December 23, 1993
    Date of Patent: March 28, 1995
    Assignee: Combustion Engineering, Inc.
    Inventors: John H. Chiu, Michael J. Hargrove, Glen D. Jukkola, Mark A. Douglas, Stuart A. Morrison, Steve Y. Wong
  • Patent number: 5395595
    Abstract: The present invention relates to a fluidized bed reactor in which olefins are polymerized or copolymerized in a bed formed by particles being polymerized and fluidized with the aid of a circulating gas. In the reactor, a circulating gas is fed from a gas space above the fluidized bed into the lower part of the reactor. The lower part of the reactor includes an annular space having an defined by an upwards tapering rotating conical surface and an outer wall defined by a downwards tapering rotating conical surface.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: March 7, 1995
    Assignee: Neste Oy
    Inventor: Matti Hamalainen
  • Patent number: 5395596
    Abstract: An apparatus and method of operating a fluidized bed reactor for combusting refuse derived fuel is disclosed. The reactor includes a fluidized furnace section 30 and stripper/cooler section 80. A downwardly sloping grid 28 extends across the furnace section 30 and stripper/cooler section 80 to a drain 78 in the stripper/cooler section 80, and directional nozzles 38 disposed in the grid fluidize the beds in the furnace section 30 and stripper/cooler section 80 and forcibly convey relatively large particulate material across the grid 28, through the furnace section 30 and stripper/cooler section 80, and to the drain 78 for disposal. A refractory layer 36 is provided along the grid 28 surface to reduce the height of the nozzles 38 within the furnace section 30, thereby helping to prevent relatively large particulate material from becoming entangled with or stuck to the nozzles 38.
    Type: Grant
    Filed: May 11, 1993
    Date of Patent: March 7, 1995
    Assignee: Foster Wheeler Energy Corporation
    Inventors: Justin P. Winkin, Walter R. Campbell, Jr., Stephen J. Goidich, John Tang, Iqbal F. Abdulally, John W. Phalen
  • Patent number: 5394811
    Abstract: Dried fuel is at least partly combusted, gasified or carbonized in the presence of cooled solid residue in a reactor. Hot solid residue, which is at temperatures in the range from 500.degree. to 1200.degree. C., is withdrawn from the reactor and is mixed with water-containing fuel in the receiving region of a mechanical mixer, without a supply of fluidizing gas. The mixture is transported with further mixing from the receiving region of the mixer through a mixing section of 1 to 10 meters to an outlet. A fuel-containing, substantially water-free mixture at a temperature in the range from above 100.degree. C. to 150.degree. C. is fed from the outlet of the mixer to the reactor. A mixer which comprises two intermeshing shafts, which rotate in the same sense, may be employed in the process.
    Type: Grant
    Filed: June 15, 1994
    Date of Patent: March 7, 1995
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventor: Hans-Jurgen Weiss
  • Patent number: 5392736
    Abstract: A fluidized bed combustion system and process is disclosed, in which full load stoichiometry is maintained at lower loads. The system and process includes an enclosure and a partition disposed in the enclosure to define a furnace section and an overfire air plenum section. A bed of combustible particulate material is formed in the furnace section and air is passed into the bed in quantities sufficient to fluidize the material and insufficient to completely combust the material. Overfire air is passed into the overfire air plenum, through control dampers in the partition and into the furnace section in quantities sufficient to completely combust the material.
    Type: Grant
    Filed: December 27, 1993
    Date of Patent: February 28, 1995
    Assignee: Foster Wheeler Energy Corporation
    Inventors: David H. Dietz, Walter R. Campbell
  • Patent number: 5390630
    Abstract: A rotary fluid bed gasifier having a combustor assembly and a stationary feed conduit which is capable of feeding a carbonaceous material and/or limestone from outside of the gasifier and delivering this material to the gasification chamber of the combustor assembly through a rotating wall of the combustor assembly, wherein the stationary conduit is centrally disposed within the combustor assembly such that the rotatable inner assembly of the combustor assembly revolves about the stationary conduit.
    Type: Grant
    Filed: June 9, 1994
    Date of Patent: February 21, 1995
    Assignee: Spinheat Ltd.
    Inventor: Michael J. Virr
  • Patent number: 5391357
    Abstract: A circulating fluidized bed reactor comprises a reaction chamber (10) with an upwardly directed flow of gas with entrained particulate solid material, a separator (18) for separating the particles from the gas flow, and a particle recycling system (23) for controlled return of the particles to the reaction chamber (10). The particle recycling system (23) may comprise means (47) for controlled return of the particles in a non-cooled condition and superposed fluid beds (55 and 59) which may be connected in parallel or in series as desired for returning particles to the reaction chamber in a more or less cooled condition. The reactor may also render it possible to return various fractions of the particles into the reactor chamber (10) at different levels.
    Type: Grant
    Filed: December 29, 1993
    Date of Patent: February 21, 1995
    Inventor: Peter Stoholm
  • Patent number: 5390612
    Abstract: A fluidized bed reactor having a furnace strip-air system and method for reducing heat content and increasing combustion efficiency of drained furnace solids in which a bed of particulate material is supported in a furnace section. A portion of the bed receives a greater amount of fluidizing gas to increase the stoichiometric conditions in the bed portion, strip relatively fine material from the particulate material in the bed portion and increase the amount of heat transferred to the flue gases. A cooler is located adjacent the furnace section for receiving particulate material from the bed portion.
    Type: Grant
    Filed: March 1, 1993
    Date of Patent: February 21, 1995
    Assignee: Foster Wheeler Energy Corporation
    Inventor: Stephen J. Toth
  • Patent number: 5378434
    Abstract: This invention relates to a novel horizontal fluid bed reactor, which in a single unit, provides for the polymerization of monomer to polymer and mixed monomers to co-polymers. Within one reactor shell the reactor contains a plurality of polymerization stages which permit the achievement of narrow residence time distribution of the produced polymer. This arrangement also creates a sufficiently tight subdivision of the reactor volume which permits a plurality of gas circulation stages of different gas compositions, as well as, polymerization temperatures.
    Type: Grant
    Filed: December 9, 1993
    Date of Patent: January 3, 1995
    Assignees: Procedyne Corp., David Bruce
    Inventors: Kenneth H. Staffin, David S. Bruce
  • Patent number: 5377627
    Abstract: Distributor device comprises at least one lower and/or one upper stationary distributor device for distribution of fuel in the form of gas and particles in a fluidized bed and is arranged above fuel feed nozzles in the bed, or at or above the upper limit of the bed. The task of the distributor device is to spread fuel, rising upwards in the bed, more evenly over a large area in the bed and to create turbulence above the bed. This is achieved by designing the distributor device with a mid-portion and upwardly-inclined wing-like members or the cone to bring about even distribution of fuel by forcing the fuel to follow an outwardly-directed horizontal or obliquely upwardly-rising flow of fuel.
    Type: Grant
    Filed: July 15, 1993
    Date of Patent: January 3, 1995
    Assignee: ABB Carbon AB
    Inventor: Mats Andersson
  • Patent number: 5378253
    Abstract: An apparatus for separating solids from a solids and gas flow in a combustor having a fluid circulating system uses a plurality of separators adjacently positioned and horizontally spaced in a path of a solids and gas flow. Each separator includes four tubes. A membrane connected between selected tubes creates a concave-shaped configuration that will capture oncoming solids particles entrained within the flue gas. In one embodiment, fluid from the fluid circulating system flows serially from an inlet into a first leading tube of a first separator through the tubes in each separator in a given row and finally through the second leading vertical tube of a last separator in that row to an outlet and back to the fluid circulating system. Connector tubes communicate with the first leading tube and the first rear tube, the first rear tube and the second rear tube, and the second rear tube and the second leading tube.
    Type: Grant
    Filed: September 28, 1993
    Date of Patent: January 3, 1995
    Assignee: The Babcock & Wilcox Company
    Inventors: Edward D. Daum, Daniel R. Rowley
  • Patent number: 5375563
    Abstract: A porous matrix, surface combustor-fluid heating apparatus comprising a combustion chamber, a cooled flow distributor proximate an inlet end of said combustion chamber and supporting a stationary porous bed within said combustion chamber, porous bed heat exchanger means embedded in said stationary porous bed and means for introducing a fuel/oxidant mixture into said stationary porous bed said fuel/oxidant mixture burning in said stationary porous bed.
    Type: Grant
    Filed: July 12, 1993
    Date of Patent: December 27, 1994
    Assignee: Institute of Gas Technology
    Inventors: Mark J. Khinkis, Tian-yu Xiong
  • Patent number: 5372096
    Abstract: The particle separation and collection system for a circulating fluidized bed combustion system is incorporated inside of the combustor. One or more particle collecting cells are formed along one of the waterwalls of the combustor with the walls of the cells also being water cooled. The cells may contain heat exchange surface and means are provided at the bottom of each cell to control the flow of particles from the cells back into the combustor.
    Type: Grant
    Filed: December 29, 1993
    Date of Patent: December 13, 1994
    Assignee: Combustion Engineering, Inc.
    Inventor: Richard S. Skowyra
  • Patent number: 5370084
    Abstract: A combustion subsystem with a circulating fluid bed boiler (12) having a pantleg configuration. The boiler includes front (22) and back (24) walls with external fluid bed heat exchangers (48) integral therewith. In addition to the conventional fuel inlets (54) which provide for entry of fuel into the side walls of the boiler through conduits connected to the seal pots (36) of solids recycle cyclones (30), supplemental fuel inlets (63, 66, 70, 72) are provided on the front and back wails of the boiler through the fluid bed heat exchangers or between adjacent fluid bed heat exchangers. The invention improves combustion efficiency in large boilers by reducing the theoretical mixing length within the boiler.
    Type: Grant
    Filed: May 26, 1994
    Date of Patent: December 6, 1994
    Assignee: Combustion Engineering, Inc.
    Inventors: Richard S. Skowyra, Bruce W. Wilhelm
  • Patent number: 5365889
    Abstract: A fluidized bed reactor and system and method utilizing same for the combustion of waste fuels in which the reactor vessel is divided into three vessels. Waste fuel is introduced into the fluidized bed within one vessel where it is mixed with bed make-up material that is controlled to provide an ideal environment for the generation of pyrolytic gases. The fluidized bed material is pneumatically and gravitationally conveyed downwardly, and injected into a fluidized bed within the second vessel where the involatile organic material undergoes combustion in an oxidizing atmosphere. The bed material in the second vessel is pneumatically conveyed upwardly and divided into two portions, one of which is recycled back to the first vessel. The other portion of the bed material in the second vessel is circulated to a fluidized bed within the third vessel where heat is recovered.
    Type: Grant
    Filed: November 13, 1992
    Date of Patent: November 22, 1994
    Assignee: Fostyer Wheeler Energy Corporation
    Inventor: John T. Tang
  • Patent number: 5363812
    Abstract: Bed temperature in a circulating fluidized bed (CFB) reactor is controlled by varying a recirculation rate of particles collected by a secondary particle separator back to the CFB reactor. Particle storage means, sized to contain sufficient inventory required for bed inventory/temperature control due to fuel/sorbent variations and/or load changes, stores particles collected by the secondary particle separator. The storage means can be either directly below the secondary particle separator or at a remote location. Particles collected by the secondary particle separator rather than by the primary particle separator are preferred due to their smaller size and lower temperature. A bed temperature control system controls the recirculation rate of these particles back to the reactor. Level sensing devices are provided on the storage means. A solids storage level control system that interacts with the bed temperature control system controls the solids inventory in the storage means via a purge system.
    Type: Grant
    Filed: February 18, 1994
    Date of Patent: November 15, 1994
    Assignee: The Babcock & Wilcox Company
    Inventors: Felix Belin, Kiplin C. Alexander, David E. James
  • Patent number: 5361728
    Abstract: A pressurized fluidized bed combustion boiler system comprising: a boiler; a filtration apparatus with ceramics filters in a flue gas system; and a louver separator as a primary stage dust separator disposed between the boiler and the filtration apparatus.
    Type: Grant
    Filed: September 14, 1993
    Date of Patent: November 8, 1994
    Assignees: Asahi Glass Company Ltd., Electric Power Development Co., Ltd.
    Inventors: Noriyuki Oda, Akira Toriyama, Katsumi Higashi, Hiroshi Maeno, Tetsuya Kunitaka, Junichi Iritani, Hideki Goto
  • Patent number: 5355725
    Abstract: The present invention is directed to a method for determining the mass flow rate of solids in a cyclone separator having an inlet for receiving a mixture of solids and gases and an outlet for discharging the separated gases. The method includes measuring the gas pressures at the inlet, in the separator, and at the outlet, and utilizing these pressure values to establish a ratio of the pressure drop across the outlet to the pressure drop across the separator. This ratio is then used to determine the mass flow rate of the solids into the cyclone.
    Type: Grant
    Filed: June 25, 1993
    Date of Patent: October 18, 1994
    Assignee: Foster Wheeler Energy Corporation
    Inventor: David H. Dietz
  • Patent number: 5351749
    Abstract: An arrangement of apparatus and process thereof for cooling hot fluid solid particles, especially hot regenerated catalytic particles are disclosed. The apparatus comprises a substantially vertical, cylindrical and close ended heat removal vessel through the shell sid passage of which is passed the fluid solid particles that flow downwardly in the form of dense phase fluidized bed, and one or more seperate heat exchange tube units through the tube side passage of which the coolant is passed and evaporized, each of said heat exchange tube units comprising a supply coolant inlet tube, a supply coolant collecting chamber, one or more heat exchange tubes, a vapour collecting chamber and a resulting vapour discharge tube, all of which constitute a close type coolant-to-vapour circulation.
    Type: Grant
    Filed: May 27, 1993
    Date of Patent: October 4, 1994
    Assignee: Sinopec Beijing Design Institute
    Inventors: Zhouping Lai, Hongyan Liu, Qiye Yang, Ziliang Liu
  • Patent number: 5347954
    Abstract: A fluidized bed combustion system in which a separator receives a mixture of flue gases and entrained particulate material from a fluidized bed in a furnace. A pressure seal valve, in the form of two ducts, connects an outlet of the separator to the furnace for recycling the separated particulate material back to the furnace. A pressure head builds up in one of the ducts and air is introduced to the other duct to dampen pressure fluctuations in the furnace and promote the flow of the particulate material back to the furnace.
    Type: Grant
    Filed: July 6, 1993
    Date of Patent: September 20, 1994
    Assignee: Foster Wheeler Energy Corporation
    Inventor: David H. Dietz
  • Patent number: 5347953
    Abstract: A fluidized bed combustion method utilizing fine and coarse sorbent feed to control the temperature of a cooling fluid such as water or steam circulating through a fluid flow circuit of a fluidized bed combustor. Fuel particles, such as coal, along with relatively fine and relatively coarse sorbent material, such as limestone, are fed into the furnace section of a fluidized bed reactor. The fuel is combusted, and a fluidizing gas such as air is introduced into the furnace section. Flue gases and entrained material pass from the furnace section, and the entrained material is separated from the flue gases. The separated entrained material passes to a recycle heat exchange section and is cooled before being passed to the furnace section. The recycle heat exchange section is provided with heat exchange surfaces which form part of a fluid flow circuit to transfer heat from the separated entrained material to a cooling fluid such as water or steam which is circulating through the circuit.
    Type: Grant
    Filed: June 3, 1991
    Date of Patent: September 20, 1994
    Assignee: Foster Wheeler Energy Corporation
    Inventor: Igbal F. Adbulally
  • Patent number: 5345883
    Abstract: A circulating fluidized bed combustion process which uses a sorbent to react with sulfur oxides employs a process for fracturing the sorbent particles to expose unreacted sorbent in the core of the particles to increase the sorbent utilization. The particles within the circulating bed are fractured by injecting water either as a liquid or as steam.
    Type: Grant
    Filed: December 31, 1992
    Date of Patent: September 13, 1994
    Assignee: Combustion Engineering, Inc.
    Inventor: Paul J. Panos
  • Patent number: 5345896
    Abstract: A reactor chamber of a fluidized bed reactor has an internal circulation of particles. Larger recirculated particles are prevented from contacting heat transfer surfaces by classifying particles adjacent the bottoms of the reactor chamber using a particle chamber having a barrier wall with holes or slots of a maximum dimension of less than about 30 mm. The heat transfer surfaces may be disposed in the particle chamber. Larger particles flow down the walls of the particle chamber into the reactor chamber, and some fine particles within the particle chamber are preferably recirculated back to the fluidized bed. The barrier wall is preferably the top wall of the particle chamber, and may be refractory lined with furrows, and/or may be formed of water tubes connected together by fins, with the holes or slots formed in the fins.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: September 13, 1994
    Assignee: A. Ahlstrom Corporation
    Inventor: Timo Hyppanen
  • Patent number: 5343830
    Abstract: A CFB reactor or combustor having an internal impact type primary particle separator provides cavity means and particle return means in an upper portion of the reactor enclosure to obtain direct and 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.
    Type: Grant
    Filed: March 25, 1993
    Date of Patent: September 6, 1994
    Assignee: The Babcock & Wilcox Company
    Inventors: Kiplin C. Alexander, Felix Belin, David E. James, David J. Walker
  • Patent number: 5343631
    Abstract: A process and apparatus for cooling coal dried in a fluid bed reactor are disclosed in which heated dried coal is separated into coarser and finer fractions and the coarser and finer fractions are separately cooled.
    Type: Grant
    Filed: February 3, 1993
    Date of Patent: September 6, 1994
    Assignee: Amax Coal West, Inc.
    Inventors: Michael W. Shackelford, Robert G. Bauer, George W. Land
  • Patent number: 5343820
    Abstract: An advanced overfire air system for NO.sub.x control designed for use in a firing system of the type that is particularly suited for use in fossil fuel-fired furnaces and a method of operating such a furnace which embodies an advanced overfire air system. The advanced overfire air system for NO.sub.x control includes multi-elevations of overfire air compartments consisting of a plurality of close coupled overfire air compartments and a plurality of separated overfire air compartments. The close coupled overfire air compartments are supported at a first elevation in the furnace and the separated overfire air compartments are supported at a second elevation in the furnace so as to be spaced from but aligned with the close coupled overfire air compartments.
    Type: Grant
    Filed: August 18, 1993
    Date of Patent: September 6, 1994
    Assignee: Combustion Engineering, Inc.
    Inventor: John L. Marion
  • Patent number: 5341753
    Abstract: A circulating fluidized bed combustor comprises a fluidized bed combustion chamber, a recirculating system for recirculating fluidized solids through the combustion chamber, and a plurality of fluid injection nozzles disposed around the walls of the combustion chamber above the loop seal returns for injecting a high velocity fluid for improved mixing gases and solids in the combustion chamber.
    Type: Grant
    Filed: February 12, 1993
    Date of Patent: August 30, 1994
    Assignee: Pyropower Corporation
    Inventor: David B. Russell
  • Patent number: 5341766
    Abstract: In association with a circulating fluidized bed reactor, a bed of particles is established in the return duce for particles from the particle separator to the combustion chamber. Inlet openings extend from the bed of particles into the combustion chamber, and the height of the particle bed is maintained above the inlet openings a sufficient distance to form a gas seal. The particles in the bed are fludized, and also transporting nozzles are arranged at different levels for transporting the particles from the bed through the inlet openings into the combustion chamber. Heat exhangers (e.g. superheaters) may be provided in the bed to recover heat from the particles.
    Type: Grant
    Filed: November 10, 1992
    Date of Patent: August 30, 1994
    Assignee: A. Ahlstrom Corporation
    Inventor: Timo Hyppanen
  • Patent number: 5339774
    Abstract: A fluidized bed steam generation system and method in which recycled flue gases are used to assist in passing solid particulate material from the separator, through the loopseal, and back into the furnace. The solid particulate material separated in the cyclone separator and passed back to the furnace is assisted by recycled flue gases which have passed through the heat recovery section, an air heater, and a baghouse. The use of the recycled flue gases decreases the oxygen content which can cause oxidizing or burning of the solid particulate material which results in overheating or agglomeration of the loopseal.
    Type: Grant
    Filed: July 6, 1993
    Date of Patent: August 23, 1994
    Assignee: Foster Wheeler Energy Corporation
    Inventor: John T. Tang
  • Patent number: 5335630
    Abstract: In a method and device for controlling power output during combustion in a pressurized fluidized bed, energy developed is taken out by heat transfer surfaces and a gas turbine, and heat is utilized in a steam turbine. The heat transfer surfaces include a high pressure section with one evaporator and a low pressure section with at least one intermediate superheater. In case of changes in the power output, the bed depth of the fluidized bed is varied, whereby heat transfer surfaces included in the evaporator are exposed or covered by the bed and production of high pressure steam, evaporation power, is controlled. Heat taken from the fluidized bed is controlled by controlling the temperature difference between the bed and low pressure stream flowing in the intermediate superheaters. High pressure steam, produced in the evaporator is superheated in a heat exchanger arranged outside the bed by low pressure steam from the intermediate superheaters before it is expanded in a high pressure steam turbine.
    Type: Grant
    Filed: October 8, 1992
    Date of Patent: August 9, 1994
    Assignee: ABB Stal AB
    Inventor: Karl-Johan Nilsson
  • Patent number: 5332553
    Abstract: In a fluidized bed reactor particles are internally circulated, moving down the walls forming the reactor chamber. A particle chamber having a particle gathering top wall with a horizontal projection area A is disposed in the downward flow of particles. Openings (e.g. holes or slots) with a controlling dimension of about 30 mm or less are provided in the top wall, the openings having total open area B less than half the area A. Heat transfer surfaces may be disposed in the particle chamber.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: July 26, 1994
    Assignee: A. Ahlstrom Corporation
    Inventor: Timo Hyppanen
  • Patent number: 5329892
    Abstract: A frame structure is provided for a bed vessel in an energy plant with higher or lower pressure in the bed vessel in relation to the surrounding space. The walls of the bed vessel are stiffened by surrounding horizontally extending, continuous frames with stiff corners, beams in the frames are built up from rolled standard beams and each individual frame is supported and guided by devices applied to the bed vessel wall. The devices make possible axial movements of the frame beams in relation to the devices. Anti-twist bars for each frame are arranged by means of crossbars rigidly attached to each frame. The crossbars extend to the adjacent frame. The ends of the crossbars mounted in a web of the adjacent frame, the ends of the crossbars at the mounting point being freely axially movable.
    Type: Grant
    Filed: December 15, 1992
    Date of Patent: July 19, 1994
    Assignee: Abb Carbon AB
    Inventor: Harald Svendsen
  • Patent number: 5325823
    Abstract: A fluidized bed reactor in which partitions disposed within a vessel form first and second furnace sections, first and second troughs and a heat exchange section such that the first trough is disposed between the first furnace section and the heat recovery section and the second trough is disposed between the second furnace section and the heat recovery section. A fluidized bed is formed in each of the furnace sections for the combustion of fuel to generate heat and to generate a mixture of combustion gases and entrained particulate solids. The mixtures from the furnace sections are received in first and second horizontal cyclone separators, both formed within the vessel for separating the entrained particulate solids from the combustion gases. Outlets extend from the horizontal cyclones to discharge the separated solids to the first and second troughs, respectively.
    Type: Grant
    Filed: December 24, 1992
    Date of Patent: July 5, 1994
    Assignee: Foster Wheeler Energy Corporation
    Inventor: Juan A. Garcia-Mallol
  • Patent number: 5325796
    Abstract: Emissions of nitrous oxide (N.sub.2 O) are lowered in a fluidized bed reactor utilizing two-staged combustion. A lower region of the furnace section is operated under substoichiometric conditions so that combustion in the lower region is incomplete, thereby inhibiting formation of N.sub.2 O and nitrogen oxides (NO.sub.x). An upper region of the furnace section is operated under oxidizing conditions to promote further combustion. An amount of particulate material is present in the upper region, and this amount of particulate material in the upper region is controlled to maintain a temperature in the upper region for destroying N.sub.2 O formed during combustion. The amount of particulate material present in the upper region may in turn be controlled by controlling the particulate material entrained from the lower region to the upper region. The temperature is also preferably controlled within a range to permit sulfur capture by sorbent particles so that emissions of N.sub.2 O, NO.sub.
    Type: Grant
    Filed: May 22, 1992
    Date of Patent: July 5, 1994
    Assignee: Foster Wheeler Energy Corporation
    Inventor: Juan A. Garcia-Mallol
  • Patent number: 5325797
    Abstract: A staged fluidized-bed combustion and filter system for substantially reducing the quantity of waste through the complete combustion into ash-type solids and gaseous products. The device has two fluidized-bed portions, the first primarily as a combustor/pyrolyzer bed, and the second as a combustor/filter bed. The two portions each have internal baffles to define stages so that material moving therein as fluidized beds travel in an extended route through those stages. Fluidization and movement is achieved by the introduction of gases into each stage through a directional nozzle. Gases produced in the combustor/pyrolyzer bed are permitted to travel into corresponding stages of the combustor/filter bed through screen filters that permit gas flow but inhibit solids flow. Any catalyst used in the combustor/filter bed is recycled. The two beds share a common wall to minimize total volume of the system. A slightly modified embodiment can be used for hot gas desulfurization and sorbent regeneration.
    Type: Grant
    Filed: August 18, 1993
    Date of Patent: July 5, 1994
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Joseph S. Mei, John S. Halow
  • Patent number: 5326252
    Abstract: A self contained catalytic heating device within which a fuel/oxidizer mixture and combustion products are held out of physical contact with a heated medium, allowing the temperature of the catalytic material to be maintained at a level that is independent of the temperature at the surface in contact with the heated medium; materials and geometric dimensions can be chosen to achieve required temperatures for catalytically coated surfaces and heating surfaces, for example in a tubular construction.
    Type: Grant
    Filed: September 4, 1991
    Date of Patent: July 5, 1994
    Inventor: Thomas Tonon
  • Patent number: 5324421
    Abstract: In a steam generator for recovering heat in a hot fluidized bed of solid particles, wherein coils of the steam generator make a 180.degree. U-bend, the U-bend portion of the coils are protected from overheating by installing an open top insulating box around the U-bend portion of the coil. In use solid particles from the circulating fluidized bed accumulate in the insulating box thus providing a non-moving layer of solid particles surrounding the U-bend which thermally insulates the U-bend portion of the coil from the higher temperature encountered in the moving fluidized bed.
    Type: Grant
    Filed: October 4, 1990
    Date of Patent: June 28, 1994
    Assignee: Phillips Petroleum Company
    Inventor: William C. Rahlwes
  • Patent number: 5320518
    Abstract: Methods and apparatus are provided for establishing and controlling the stability and movement of a reaction wave of reacting gases in a matrix of solid heat-resistant matter, wherein such reacting gases may be recuperatively pre-heated. At least a portion of the bed is initially preheated above the autoignition temperature of the mixture whereby the mixture reacts upon being introduced into the matrix thereby initiating a self-sustaining reaction region, after which the pre-heating can be terminated. The stability and movement of the wave within the matrix is maintained by monitoring the temperatures along the flowpath of the gases through the bed and adjusting the flow of the gases and/or vapors or air to maintain and stabilize the wave in the bed. The method and apparatus provide for the reaction or combustion of gases to minimize NO.sub.x and undesired products of incomplete combustion.
    Type: Grant
    Filed: September 15, 1992
    Date of Patent: June 14, 1994
    Assignee: Thermatrix, Inc.
    Inventors: John D. Stilger, Richard J. Martin, Mark R. Holst
  • Patent number: 5316735
    Abstract: In a vertical cylindrical casing (1) of the apparatus along the axis thereof a gas-supplying pipe (8) is disposed, the end face (11) of which is disposed above a gas-distributing grating (3) at the level of the height of a fluidized bed formed thereon and in which a tube (12) is arranged with a swirler (13) inserted thereinto, said tube forming an annular gap (14) with the pipe (8). On the gas-supplying pipe (8) and on the gas-distributing grating (3) truncated cones (15, 16) are arranged coaxially, the upper end face (17) of the external cone (16) being disposed below the end face (11) of the gas-supplying pipe (8). In the upper part of the casing (1) in front of the inlet to an axial gas-discharging pipe (7) a baffle cone (19) is mounted.
    Type: Grant
    Filed: September 23, 1992
    Date of Patent: May 31, 1994
    Inventors: Oleg R. Ivanov, Mikhail I. Snegirev, Makhail K. Chistyakov, Vladimir M. Razhev, Vladimir I. Budantsev, Jury I. Kipriyanov, Viktor A. Zaitsev, deceased, by Galina M. Zaitseva, administrator, by Natalya V. Zaitseva, administrator
  • Patent number: 5313913
    Abstract: A pressurized internal circulating fluidized-bed boiler is incorporated in a combined-cycle electric generating system in which a fuel such as coal, petro coke or the like is combusted in a pressurized fluidized bed and an exhaust gas produced by the combusted fuel is introduced into a gas turbine. The pressurized internal circulating fluidized-bed boiler includes a pressure vessel, a combustor disposed in the pressure vessel and a primary fluidized bed incinerating chamber provided with an air diffusion device. A thermal energy recovery chamber is partitioned from the primary fluidized bed incinerating chamber by an inclined partition wall. A fluidizing medium flows into and out of the primary incinerating chamber and the thermal energy recovery chamber.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: May 24, 1994
    Assignee: Ebara Corporation
    Inventors: Takahiro Ohshita, Shuichi Nagato, Norihisa Miyoshi, Seiichiro Toyoda
  • Patent number: 5311842
    Abstract: A fluidized bed water tube boiler comprising a fluidized bed combustion section including a fluidized bed formed from a continuous water tube wall, a free-board section for burning volatile components produced in the fluidized bed combustion section, and a convective heat transfer section comprised of a steam drum and a water drum connected to the downstream side of the freeboard section through water tubes for recovering heat from combustion exhaust gas; wherein the fluidized bed combustion section and the freeboard section are formed as separable modules which are connected to each other, and circulation of a boiler water between the fluidized bed combustion section and the convective heat transfer section is separated from that between the freeboard section and the convective heat transfer section.
    Type: Grant
    Filed: April 16, 1993
    Date of Patent: May 17, 1994
    Assignee: Ebara Corporation
    Inventors: Shuichi Nagato, Takahiro Ohshita, Masaji Kamisada, Norihisa Miyoshi, Hiroshi Ishibe
  • Patent number: 5307765
    Abstract: A rotary fluid bed gasifier which comprises: a rotatable drum having a circumferentially extending wall which is permeable to gases; a means for feeding a fluidizing gas through the wall into the drum; a bed of particles which, at least when the gasifier is in use, is supported on an internal face of the wall and is fluidized by the fluidizing gas; an outlet means for receiving an oil-in-water emulsion from outside the gasifier and delivering the oil-in-water emulsion to the drum; a means for introducing steam into the drum; a de-NO.sub.x boiler having a quench zone and a nitrogen fixing zone; a means for introducing secondary air disposed between the quench zone and the nitrogen fixing zone; and a means for introducing tertiary air disposed between the de-NO.sub.x boiler and a main boiler or furnace.
    Type: Grant
    Filed: December 9, 1992
    Date of Patent: May 3, 1994
    Inventor: Michael J. Virr
  • Patent number: 5308585
    Abstract: Hot solids coming from a fluidized bed reactor are passed through the cooling apparatus and at least in part are recycled to the fluidized bed reactor. In the cooling apparatus the hot solids flow first through a first fluidized bed and then flow downwardly through a gas-collecting space to a second fluidized bed, which is provided with cooling coils and in which the solids flow downwardly to a solids transfer passage and are then raised through a third fluidized bed to a discharge line. The system is controlled to cause solids coming from the first fluidized bed to flow through the gas-collecting space directly to the discharge line.
    Type: Grant
    Filed: December 29, 1992
    Date of Patent: May 3, 1994
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventors: Michael Stroder, Johannes Albrecht, Martin Hirsch, Rainer Reimert, Wladyslaw Lewandowski, Rudolf Kral
  • Patent number: 5302352
    Abstract: In a steam generator for recovering heat in a hot fluidized bed of solid particles, wherein generally horizontally oriented coils of the steam generator make a 180.degree. U-bend, the U-bend portion of the coils are protected from overheating by installing an open top insulating box around the U-bend portion of the coil. In use solid particles from the circulating fluidized bed accumulate in the insulating box thus providing a non-moving layer of solid particles surrounding the U-bend which thermally insulates the U-bend portion of the coil from the higher temperature encountered in the moving fluidized bed.
    Type: Grant
    Filed: December 3, 1992
    Date of Patent: April 12, 1994
    Assignee: Phillips Petroleum Company
    Inventor: William C. Rahlwes
  • Patent number: 5299532
    Abstract: A fluidized bed combustion system and method in which a plurality of enclosures, each having a furnace section and integral recycle section are joined using common walls. Openings are provided in lower portions of the common walls for permitting the fluidized bed material to flow between adjacent or opposing furnace sections and between adjacent recycle sections. Openings are also provided in upper portions of the common walls for equalizing the gas pressure between the adjacent or opposing furnace sections.
    Type: Grant
    Filed: November 13, 1992
    Date of Patent: April 5, 1994
    Assignee: Foster Wheeler Energy Corporation
    Inventor: David H. Dietz
  • Patent number: 5297622
    Abstract: A method is provided for cooling of particulate material from a combustion plant, especially intended for cooling of fine-grained dust which has been separated from the flue gases from a PFBC power plant, and in which the material is transported pneumatically with the flue gas as transport means. A cooler is provided at the inlet of which there is a space for separation of the particulate material from the transport gas. The transport gas is removed via a gas cleaner. The particulate material is collected in a duct where it forms a particulate column. The duct includes cooling modules, suitably water-cooled, which cool the material on its way down through the duct. The duct comprises devices for the supply of a gas for stirring the material in the duct while the remaining flue gas is being separated from the particulate column.
    Type: Grant
    Filed: October 20, 1992
    Date of Patent: March 29, 1994
    Assignee: ABB Stal AB
    Inventors: Roine Brannstrom, Antal Molnar
  • Patent number: 5293843
    Abstract: A fluidized bed combustor or gasifier has a combustion chamber(s) with a non-symmetrical horizontal cross section. The chamber may be trapezoidal, hemispherical, or may have five or more side walls of at least two different lengths. The walls of the combustion chamber may be water tube panels. An external pressure vessel surrounds the combustion chamber(s) and associated particle separator(s), and may be spherical or cylindrical.
    Type: Grant
    Filed: December 9, 1992
    Date of Patent: March 15, 1994
    Assignee: A. Ahlstrom Corporation
    Inventors: Steven J. Provol, David Russell
  • Patent number: 5282506
    Abstract: The invention relates to a process for cooling gases using a circulating fluidized bed technique, wherein gas is conveyed through a fluidized bed formed by circulating fluidized bed material so that part of the circulating fluidized bed material is driven along with the gas flow and whereby the circulating fluidized bed material entrained in the gas flow is separated from the gas flow and returned into the fluidized bed, and wherein at least part of the cooling is carried out by cooling the circulating fluidized bed material stream to be returned. The process is characterized in that substantially the entire cooling is realized by cooling the circulating fluidized bed material stream to be returned in a heat exchanger (10) separate from the gas flow duct, in which event the cooling of the gas stream is effected by means of the circulating fluidized bed material stream returned to the fluidized bed and having a temperature lower than that of the fluidized bed.
    Type: Grant
    Filed: March 8, 1993
    Date of Patent: February 1, 1994
    Assignee: Tampella Power Oy
    Inventor: Seppo Ruottu
  • Patent number: 5277151
    Abstract: An integral circulating fluidized bed steam generation system having a particle separator which is formed by the membrane walls of the reactor chamber. The particle separator has a serpentine configuration which includes a first turn which is capable of causing the solid particles in the flue gas to move toward the rear membrane wall and a second turn which is capable of causing smaller sized solid particles and the flue gas to be disposed between the front membrane wall and the larger sized solid particles wherein the flue gas passes through the solid particles to a discharge conduit which is disposed within the rear membrane wall and wherein the smaller sized solid particles are retained between the front membrane wall and the larger sized solid particles. The particle separator also includes a means for recycling the solid particles from the particle separator to the reactor chamber.
    Type: Grant
    Filed: January 19, 1993
    Date of Patent: January 11, 1994
    Assignee: Tampella Power Corporation
    Inventor: Kent L. Paulhamus