Waste Heat Patents (Class 122/7R)
  • Patent number: 6155210
    Abstract: The invention relates to a method of firing black liquor in recovery boilers where the intention is to get fumes having a low content of nitrogen oxides (NO.sub.x). The invention is characterized in that a part of the combustion air is added as a last portion at a level on a very high level so that a reducing atmosphere will exist in a very great part of the boiler and during a long period of time of at least 3-5 seconds. The invention also includes a recovery boiler for carrying out the above said method.
    Type: Grant
    Filed: July 19, 1999
    Date of Patent: December 5, 2000
    Assignee: Kvaerner Pulping AB
    Inventor: Nils Gustav Lindman
  • Patent number: 6141956
    Abstract: In a combined power generation plant, an exhaust gas boiler (2) consists of a high-pressure reheat type steam system, in which fuel is supplied to this exhaust gas boiler 2, and the supplied fuel undergoes catalytic reaction in combustion catalysis sections (NOx removal sections) 18 and 19 to increase the temperature of exhaust gas, whereby the power generation efficiency is improved.
    Type: Grant
    Filed: July 1, 1998
    Date of Patent: November 7, 2000
    Assignee: Mitsubishi Heavy Industries, Inc.
    Inventors: Masaki Iijima, Tetsuya Imai
  • Patent number: 6125794
    Abstract: A heat recovery system, the system having a fuel burner assembly. The fuel burner assembly having a pilot burner, an ignition source such as, an ignition transformer, a turbo compressed air inlet duct, a primary housing accommodating a burner rod and nozzle assembly and a secondary housing made of a combustion chamber, having an upstream secondary air mixing assembly and an air diffuser assembly.The fuel burner assembly being operably connected down stream to a heat transfer and recovery system having one or more, preferably two, heat exchangers of the convective heat exchange type and an exhaust or stack for the exit of spent flue gases. The fuel burner assembly being operably connected upstream to a turbo charger/turbo compressor. The turbo charger/turbo compressor being provided with a start up mechanism, the start up mechanism comprising an air eductor assembly, external air supply feed line, an external fuel supply source, a liquid/gaseous fuel burner and a mixing chamber assembly.
    Type: Grant
    Filed: August 11, 1998
    Date of Patent: October 3, 2000
    Assignee: Thermax Limited
    Inventors: Narendra Dattatraya Joshi, Dilip Waman Bapat, Alten Carmo Lobo, Samir Vasudeo Kulkarni, Charles Philominraj
  • Patent number: 6105538
    Abstract: A self-regulating exhaust gas boiler intended for the recovery of thermal energy from the exhaust gases of diesel engines or the like, has a steam/water cylinder acting as the water and steam space. There is a convection part acting as the vaporizer and being fitted in the vertical orientation between the steam/water cylinder and a lower cylinder, or the like, and connected to it. There is at least one downcomer interconnecting the steam/water cylinder and the lower cylinder, or the like. At least one valve or corresponding device regulates the amount of water and the water level in the convection part is mounted between the steam/water cylinder and the lower cylinder, or the like, preferably in the lower section of the downcomer.
    Type: Grant
    Filed: June 18, 1999
    Date of Patent: August 22, 2000
    Assignee: Aalborg Industries A/S
    Inventor: Pasi Aaltonen
  • Patent number: 6101982
    Abstract: A method and an arrangement for preheating the fuel for a firing plant which is operated with liquid or gaseous fuel, which is fed to the firing plant via a feed line, having at least one heat-exchanger unit which is thermally coupled to the feed line and through which heat is transferred from a heating medium, which is directed in a heating circuit, to the fuel.The invention is distinguished by the fact that the pressure at which the fuel is directed in the feed line is greater than the pressure at which the heating medium is directed in the heating circuit, at least in the region of the heat exchanger.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: August 15, 2000
    Assignee: Asea Brown Boveri AG
    Inventors: Kurt Fischer, Ralf Kuske, Erhard Liebig
  • Patent number: 6092490
    Abstract: The water flow circuit for a heat recovery steam generator is a hybrid system which combines a circulating drum type circuit and a once-through circuit. A low pressure evaporator is designed for natural or forced circulation and a high pressure evaporator is designed for once-through flow. Orifices may be located in the inlet of the evaporator tubes for flow stability and an intermediate header between the evaporator and high pressure superheater improves stability, minimizes orifice pressure drop and equalizes pressure losses between evaporator tubes.
    Type: Grant
    Filed: April 3, 1998
    Date of Patent: July 25, 2000
    Assignee: Combustion Engineering, Inc.
    Inventors: Donald W. Bairley, Mark Palkes, Richard E. Waryasz
  • 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: 6019070
    Abstract: A once-through steam generator or boiler of simple modular construction that utilizes vertical heat transfer tubes, intended primarily for heat recovery in combined cycles. It utilizes a novel method of assembly and operation that make it particularly effective for large combined cycles. Circuit assemblies with a once-through flow path are the key building blocks used to assemble boilers to fit any size gas turbine. They are individually bench fabricated in a horizontal plane. The boiler is manufactured by sequentially stacking individual circuit assemblies in parallel thereby building a circuit module. During the stacking process the inlet and outlet of each circuit assembly are connected to headers to allow the modules to be erected into a heat transfer bundle. For large boilers several transportable circuit modules are interconnected in the field to complete a once-through boiler.
    Type: Grant
    Filed: December 3, 1998
    Date of Patent: February 1, 2000
    Inventor: Thomas E. Duffy
  • 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: 5946901
    Abstract: A heat recovery steam generator has a housing defining a horizontally oriented exhaust gas stream path from a gas turbine. The housing has a diffuser portion and a full cross-section portion containing heat recovery assemblies. The diffuser portion expands the exhaust gas stream from the duct at the gas turbine exhaust to the full cross-section portion. Positioned in the diffuser is a diffuser heat recovery assembly for heat recovery and control of the flow distribution of the exhaust gas flow stream.
    Type: Grant
    Filed: December 17, 1997
    Date of Patent: September 7, 1999
    Assignee: Combustion Engineering, Inc.
    Inventors: Wesley P. Bauver, Paul F. Miller
  • Patent number: 5924389
    Abstract: The water flow circuit for a heat recovery steam generator includes both a low pressure circuit and a high pressure circuit. Both circuits are designed for once-through flow and both include evaporators with rifled tubing. A pressure equalizing header may be located between the evaporator and superheater and orifices may be located at the inlet to the evaporator for flow stability.
    Type: Grant
    Filed: April 3, 1998
    Date of Patent: July 20, 1999
    Assignee: Combustion Engineering, Inc.
    Inventors: Mark Palkes, Richard E. Waryasz
  • Patent number: 5893411
    Abstract: A heat exchanger has a first tube bundle for circulating a first fluid, a second tube bundle for circulating a second fluid, and a shell which accommodates the tube bundles arranged in series in the shell, so that when a third fluid is circulated through the shell it successively contacts the tube bundles for a successive heat exchange between the third fluid and a respective one of the two first-mentioned fluids, to provide a heat transfer between three fluids.
    Type: Grant
    Filed: January 9, 1997
    Date of Patent: April 13, 1999
    Inventor: Ari Nir
  • Patent number: 5873238
    Abstract: A startup cooling steam generator (36) is disclosed. The generator provides cooling steam (40) to a combustion turbine (2) shortly after the combustion turbine begins to operate. Cooling steam is generated in a once-through system by passing hot exhaust gases generated by the combustion turbine over an immediately adjacent metal tubing apparatus filled with liquid. The startup steam generator (35) is operable in parallel with the main heat recovery steam generator (6).
    Type: Grant
    Filed: December 23, 1996
    Date of Patent: February 23, 1999
    Assignee: Siemens Westinghouse Power Corporation
    Inventor: James C. Bellows
  • Patent number: 5873329
    Abstract: A refractory lining in the transition section of a gasifier to the waste heat boiler with claws/brackets for supporting refractory shaped bricks. Each claw is suspended on hooks in a pipe branch and is protected from overheating by cooling tubes. The refractory lining is supported in the tube bundle by brackets, which are arranged one on top of another and are welded to webs tube-web-tube welding of the tube bundle. The lower bracket at the cooling tube bundle and the horizontal tube wall are protected against clogging with slag by a refractory mass with a drip nose. Expansion joints are provided between the shaped brick segments under the brackets, whereas ring-shaped fiberboard segments are inserted above the claw.
    Type: Grant
    Filed: September 11, 1996
    Date of Patent: February 23, 1999
    Assignee: MAN Gutehoffnungshutte Aktiengesellschaft
    Inventors: Jurgen Heering, Klaus Kohnen, Duane Brooker
  • Patent number: 5852990
    Abstract: A waste heat boiler for cooling a hot process stream includes a plurality of heat exchanging tubes within a cylindrical shell, an outlet chamber for withdrawing the cooled process stream, an insulated by-pass tube having an outlet end in the outlet chamber, and an injection nozzle in the outlet chamber for control of flow of the hot process stream through the by-bass tube by injection of a fluid into the by-pass tube outlet end.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: December 29, 1998
    Assignee: Haldor Topsoe A/S
    Inventor: Ivar Ivarsen Primdahl
  • Patent number: 5845703
    Abstract: A heat recovery system has with a first tube bundle for circulating a first fluid, a second tube bundle for circulating a second fluid, and a shell which accommodates the tube bundles arranged in the shell, so that when a third fluid is circulated through the shell it contacts the tube bundles for a heat transfer between the third fluid and the two first-mentioned fluids, to provide a heat transfer between three fluids.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: December 8, 1998
    Inventor: Ari Nir
  • Patent number: 5823760
    Abstract: A method of using internal combustion engine exhaust in a combined cycle power plant is disclosed, wherein the quality and distribution of exhaust to the boiler space of a steam generated electric power plant is controlled to achieve greater system efficiencies. Outside air is blended only with that portion of the exhaust that passes through the burner ports as secondary or higher level combustion gas. The remainder of the exhaust is provided to the boiler space by a route other than through the burner.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: October 20, 1998
    Assignee: Wartsila Diesel, Inc.
    Inventors: F. Mack Shelor, Robert Bianco
  • Patent number: 5820362
    Abstract: A furnace for heating a process fluid stream which includes means for efficiently controlling a flow of the process fluid stream through an adjunct loop of the fluid stream. The adjunct loop comprises a heat exchange system in which a portion of the process fluid stream collects heat from flue gases being emitted from the furnace and donates heat to combustion air being used in the furnace. Valve means is positioned downstream of a pump and in connection with the fluid stream in order to constantly replenish a small portion of fluid in the adjunct loop with fresh process fluid. The positioning of the valve means downstream of the pump permits more efficient control of the heat exchange system. One form of valve means may be a valve which will permit a small amount of fluid to continue to flow between the fluid stream and the adjunct loop during a non-operating mode of the adjunct loop heat exchange component.
    Type: Grant
    Filed: June 12, 1997
    Date of Patent: October 13, 1998
    Assignee: The G. C. Broach Company
    Inventor: George C. Broach
  • Patent number: 5816796
    Abstract: A furnace for heating a process fluid stream which includes means for precisely controlling the temperature of pre-heated combustion air. The system includes a process fluid stream being heated within the furnace and an adjunct loop fluid stream line which acts as a heat exchange system by communication with the process fluid stream. The adjunct loop comprises a heat collecting leg positionable within the combustion area of the furnace and a heat donating leg positionable adjacent a source of combustion air. Manipulation of the flow of process fluid through the heat donating leg provides control of the temperature of the combustion air and consequently control of the stack exhaust temperature. A valve system, which may be manually controlled or thermostatically controlled responds to a present, or desired, temperature of the stack exhaust.
    Type: Grant
    Filed: June 12, 1997
    Date of Patent: October 6, 1998
    Assignee: The G. C. Broach Company
    Inventor: George C. Broach
  • Patent number: 5803020
    Abstract: The invention relates to a recovery boiler for combustion of waste liquors. It comprises a furnace whose base and walls include a multiplicity of liquid-cooled tubes and whose base (21) constitutes a collection point for inorganic substances in molten form, with air and waste liquor being introduced into the furnace and the combustion gases being conveyed upwards in the boiler. The invention is characterized essentially in that the cross-sectional area of the furnace at a first lower level (1) exceeds the cross-sectional area of the furnace at a second level (2) higher up in the furnace.
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: September 8, 1998
    Assignee: Kvaerner Pulping Technologies AB
    Inventor: Anders Palmgren
  • 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: 5769156
    Abstract: An otherwise conventional recovery boiler for burning black liquor requires less capital investment and takes up less space by constructing the economizers in a particular manner. At least first and second economizers are provided for preheating feed water utilizing flue gas from combustion of the black liquor. The economizers are positioned substantially side-by-side, in the width dimension of the recovery boiler furnace, and connected in such a way that flue gas leaving the first economizer passes in a substantially transverse horizontal direction and then through a substantially vertical intra-economizer flow channel into the second economizer. A boiler bank may be connected between the superheater section of the recovery boiler and the first economizer, and any number of economizers may be utilized.
    Type: Grant
    Filed: May 31, 1996
    Date of Patent: June 23, 1998
    Assignee: Ahlstrom Machinery Oy
    Inventor: Jan Storbacka
  • Patent number: 5765509
    Abstract: A mixed-pressure waste-heat boiler (7) has a forced-flow steam generator, essentially composed of a low-pressure economizer (15), of a low-pressure drum (17) and of a low-pressure evaporator (16), and a once-through forced-flow steam generator, essentially composed of a high-pressure economizer (21), of a high-pressure evaporator (22) and of a high-pressure superheater (23). The high-pressure economizer (21) is fed from the steam drum (17) of the forced-circulation steam generator via a high-pressure feed pump (20). Arranged between the high-pressure evaporator (22) and high-pressure superheater (23) is a separation bottle (25) which is connected to the steam drum (17) via a recirculation line (26). During startup, until superheated conditions are reached at the outlet of the high-pressure evaporator (22), high-pressure saturated water is recirculated into the drum (17) of the forced-circulation steam generator via the separation bottle (25).
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: June 16, 1998
    Assignee: Asea Brown Boveri AG
    Inventors: Erhard Liebig, Christoph Ruchti
  • Patent number: 5762031
    Abstract: A vertical boiler with horizontal evaporator tubes is provided. The evaporator is divided into two sections, which are connected in parallel to the drum. The first evaporator section relies on the feedwater pump to provide forced circulation. The second evaporator section relies primarily on natural circulation but may also be assisted by the feedwater pump. This design provides a vertical boiler which is reliable under all operating conditions, including start-up, transient conditions, and steady state conditions, without requiring the use of circulating pumps or an auxiliary energy source (steam, water, gas, etc.).
    Type: Grant
    Filed: April 28, 1997
    Date of Patent: June 9, 1998
    Inventor: Arkadiy M. Gurevich
  • Patent number: 5730088
    Abstract: Heat recovery apparatus for extracting heat from a hot flue gas stream especially useful on a marine vessel. The apparatus includes a housing having opposite outer end walls, opposite outer side walls, a top wall and a bottom wall with a heat exchanger extending between the end walls spaced downwardly below the top wall, above the bottom wall and inwardly of the outer side walls. An inlet chamber is formed in the housing having an inlet opening in one of the end walls above the heat exchanger for receiving the hot flue gas stream and the inlet chamber includes a downwardly sloping wall for directing the incoming hot flue gas stream to flow downwardly through the heat exchanger toward the bottom wall. A pair of inner side walls are provided on opposite sides of the heat exchanger spaced inwardly of the outer side walls for directing the hot flue gas stream downwardly through the heat exchanger to a low level above the bottom wall.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: March 24, 1998
    Assignee: DB Riley, Inc.
    Inventors: Robert J. Foley, David V. Lesneski, William J. Fidurko, Brian Kassabian
  • Patent number: 5701829
    Abstract: An apparatus for use in the pulp industry for recovering heat in the spent liquor recovery boiler, whereby the boiler walls are formed of water-cooled tubes connected to the water/steam circulation system of the boiler. Supply of air into the lower section of the furnace is effected symmetrically through air ports which are disposed at equal distances from the center of the furnace. The lower section of the furnace is preferably cylindrical and connected to a separate cooling medium circulation system.
    Type: Grant
    Filed: April 13, 1995
    Date of Patent: December 30, 1997
    Assignee: Ahlstrom Machinery Corporation
    Inventor: Keijo Raak
  • Patent number: 5697210
    Abstract: A fully-fired combined plant includes a boiler, a boiler feed air line provided with an air heater for feeding heated air to the boiler, a gas turbine, a gas turbine exhaust gas line connected to the gas turbine and the boiler feed air line downstream of the air heater for feeding exhaust gas from the gas turbine into the boiler feed air line. A shutter is provided on the gas turbine exhaust gas line for shutting the line at the time the operation of the gas turbine is stopped, and a ventilator is provided on the gas turbine exhaust gas line on the upstream side of the shutter with respect to a gas turbine exhaust gas flow for ventilating the gas turbine exhaust gas line on the upstream side of the shutter.
    Type: Grant
    Filed: August 15, 1995
    Date of Patent: December 16, 1997
    Assignee: Hitachi, Ltd.
    Inventor: Akihiro Kawauchi
  • Patent number: 5660037
    Abstract: A method and apparatus is disclosed for converting a reheat steam turbine plant to a non-reheat, combined cycle plant without requiring internal modification of the steam turbine unit. A reheat steam turbine power plant with a boiler and a steam turbine with a plurality of turbine sections, receiving steam under pressure and successively expanding the steam through the turbine sections, is converted to a non-reheat combined cycle plant by replacing the boiler with a dual-pressure heat recovery steam generator capable of producing main steam and secondary steam at differential temperature and pressure and by installing a trimming system to allow adjustment of the pressure drop between the exhaust of the first turbine section and the inlet of the second turbine section to prevent damage to the turbine blades.
    Type: Grant
    Filed: June 27, 1995
    Date of Patent: August 26, 1997
    Assignee: Siemens Power Corporation
    Inventor: Heinz Termuehlen
  • Patent number: 5660799
    Abstract: To achieve a high degree of heat recovery by decomposing surplus ammonia present on the downstream side of a denitrator in an exhaust gas boiler while preventing the deposition of acid ammonia sulfate on low temperature heating tubes, an exhaust gas boiler includes a residual ammonia decomposer which is disposed at a location downstream of the denitrator and between two divided high pressure evaporators.
    Type: Grant
    Filed: May 11, 1995
    Date of Patent: August 26, 1997
    Assignee: Mitsubishi Jukogyo Kabushiki Kaisha
    Inventors: Toshiki Motai, Norihisa Kobayashi
  • Patent number: 5657686
    Abstract: The invention describes a method and apparatus for controlling the temperature of the floor of a cooking oven by utilizing a recirculating primary heat transfer fluid made to flow through a heat exchanger located in an oven floor. After traveling through the oven floor and absorbing heat, the primary fluid travels to an external liquid-to-liquid heat exchanger wherein the primary fluid transfers heat to a secondary circulating heat transfer fluid. The primary fluid is then recirculated through the oven floor to maintain the floor at a predetermined temperature. The heated secondary fluid may then be utilized for other processes such as in the conveyor belt washing tank of the oven, or it may be discarded. The primary heat transfer fluid may be a thermal oil having a boiling point substantially in excess of 212.degree. F., and having other properties designed to prevent the corrosion, plugging, and fouling of the heat exchanger located in the oven floor. The second fluid is preferably water.
    Type: Grant
    Filed: February 18, 1994
    Date of Patent: August 19, 1997
    Assignee: Stein, Inc.
    Inventors: Ramesh M. Gunawardena, Ronald D. Lemke
  • Patent number: 5642614
    Abstract: An improved gas turbine combined cycle system having a diffuser duct between the gas turbine and steam generator. The diffuser duct has boundary layer suction to prevent gas jet separation, thereby reducing pressure loss and improving gas velocity profiles in the duct, while eliminating the need for internal flow controls. The gas turbine combined cycle system can be vertically oriented to reduce the plan area of the system and provide for convenient use of a symmetrical diffuser duct and the use of forced circulation on the water side of the steam generator.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: July 1, 1997
    Assignee: Combustion Engineering, Inc.
    Inventors: Carl Richard Bozzuto, Joseph David Bianca, Walter Franklin Siddall
  • Patent number: 5643522
    Abstract: A system for curing composite structures. A hollow bladder having opposing open ends is secured within a metal pressure vessel so as to define an annular space within the vessel surrounding the bladder. The open ends of the bladder are sealably attached to opposing entrances formed in the pressure vessel so that the bladder is sealed from communication with the vessel and is accessible through the opposing openings. An uncured composite part can be inserted into the bladder. Preheated and pressurized fluid is circulated through the annular space and thus around the bladder in order to cure the composite part. The composite part may also be encapsulated within a forming bladder member which is then removably inserted into the pressure bladder.
    Type: Grant
    Filed: December 12, 1994
    Date of Patent: July 1, 1997
    Inventor: James F. Park
  • Patent number: 5628179
    Abstract: In a combined cycle system including a gas turbine, a steam turbine and a heat recovery steam generator (HRSG), wherein gas turbine exhaust gas is used in the heat recovery steam generator for heating steam for the steam turbine, the gas turbine exhaust gas flowing from an entry end to an exit end of the HRSG, and wherein the HRSG includes at least one high pressure evaporator arranged to supply steam to a superheater including multiple passes including a first pass at one end thereof adjacent the evaporator, and a final pass adjacent an opposite end thereof and adjacent the entry end of the heat recovery steam generator, and one or more intermediate passes between the first and final passes, the improvement comprising an attemperating conduit not exposed to the gas turbine exhaust gas, connecting the one end and the opposite end of the superheater, bypassing the intermediate passes to thereby introduce cooler superheated steam from the one end into the superheater at the opposite end.
    Type: Grant
    Filed: April 5, 1995
    Date of Patent: May 13, 1997
    Assignee: General Electric Co.
    Inventor: Leroy O. Tomlinson
  • Patent number: 5626102
    Abstract: A heat recovery system for a boiler has a tank separator connectable to a boiler and receiving a liquid from the boiler as well as separating the liquid into a blow down liquid and a flush vapor, a heat exchanger having an upstream portion and a downstream portion and receiving a make up water to be heated, the tank separator being connected with the upstream portion of the heat exchanger so as to apply hot blow down water into the upstream portion of the heat exchanger therefore to heat the make up water in the upstream portion of the heat exchanger by heat given out by the blow down water, the heat exchanger further having a downstream portion connected with the upstream portion so that the make up water heated by the heat given out by the blow down water further flows into the downstream portion of the heat exchanger, the tank separator being connected with the downstream portion of the heat exchanger so as to supply the flush steam into the downstream portion of the heat exchanger and further heat the mak
    Type: Grant
    Filed: March 14, 1996
    Date of Patent: May 6, 1997
    Inventor: Ari Nir
  • Patent number: 5603803
    Abstract: A method and apparatus for use in the pulp industry for recovering heat in the spent liquor recovery boiler, whereby the boiler walls are formed of water-cooled tubes connected to the water/steam circulation system of the boiler. The lower section of the boiler is defined by water tubes connected to a separate water circulation system of a forced type. Thus, heat is preferably recovered in the lower section of the boiler by a separate water circulation system having a lower pressure than in the water/steam circulation system of the boiler.
    Type: Grant
    Filed: April 13, 1995
    Date of Patent: February 18, 1997
    Assignee: Ahlstrom Machinery Corporation
    Inventor: Keijo Raak
  • Patent number: 5525053
    Abstract: A method of using internal combustion engine exhaust in a combined cycle power plant is disclosed, wherein the quality and distribution of exhaust to the boiler space of a steam generated electric power plant is controlled to achieve greater system efficiencies. Outside air is blended only with that portion of the exhaust that passes through the burner ports as secondary or higher level combustion gas. The remainder of the exhaust is provided to the boiler space by a route other than through the burner.
    Type: Grant
    Filed: December 1, 1994
    Date of Patent: June 11, 1996
    Assignee: Wartsila Diesel, Inc.
    Inventor: F. Mack Shelor
  • Patent number: 5478440
    Abstract: The invention relates to a method and apparatus for use in the pulp industry for improving the safety of a spent liquor recovery boiler, such as a soda recovery boiler. The boiler comprises, for recovering chemical and energy, a furnace cooled by water tubes and connected to the water/steam circulation system of the boiler, the cooling of the bottom of the furnace being provided by a separate cooling circulation. The separately cooled lower section of the furnace is provided by separating the bottom or the bottom and part of the furnace walls from the boiler water circulation system. This separated section is supplied with a cooling fluid of its own which may be a gas (e.g. air or inert gas) or a liquid (e.g. molten zinc) which does not cause an explosion of it contacts the melt of the furnace.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: December 26, 1995
    Assignee: A. Ahlstrom Corporation
    Inventor: Raimo Paju
  • Patent number: 5467591
    Abstract: An improved gas turbine combined cycle system having a diffuser duct between the gas turbine and steam generator. The diffuser duct has boundary layer suction to prevent gas jet separation, thereby reducing pressure loss and improving gas velocity profiles in the duct, while eliminating the need for internal flow controls. The gas turbine combined cycle system can be vertically oriented to reduce the plan area of the system and provide for convenient use of a symmetrical diffuser duct and the use of forced circulation on the water side of the steam generator.
    Type: Grant
    Filed: December 30, 1993
    Date of Patent: November 21, 1995
    Assignee: Combustion Engineering, Inc.
    Inventors: Carl R. Bozzuto, Joseph D. Bianca, Walter F. Siddall
  • Patent number: 5452686
    Abstract: Waste heat boiler comprising within a cylindrical shell a plurality of heat exchanging tubes having an inlet end and outlet end;attached to the shell, means for introducing water on shellside of the tubes;means for introducing a hot process stream into the inlet end of the tubes and passing the gas stream through the tubes in indirect heat exchange with the water on the shellside of the tubes to produce water/steam and to cool the introduced process stream;means for withdrawing produced water/steam, and means for withdrawing the cooled gas stream;wherein the tubes are arranged in at least two tube bundles each of which is provided with means for adjusting flow distribution and flow rate of the hot gas stream between the tube bundles to control the production of steam and the cooling of the process stream.
    Type: Grant
    Filed: March 23, 1994
    Date of Patent: September 26, 1995
    Assignee: Haldor Topsoe A/S
    Inventor: Henrik O. Stahl
  • Patent number: 5445658
    Abstract: The gasification apparatus for gasification of finely divided combustible material under pressure includes a gasification reactor which produces a crude gas, a quenching pipe and a convection-heated boiler with a boiler housing, all mounted inside a pressurized vessel. A gas flow guiding device is provided above the quenching pipe for conducting a mixed gas flow containing the crude gas and a quenching gas from the quenching pipe into the convection-heated boiler which surrounds the quenching pipe concentrically. A gas outlet device is provided for the gas flow from the convection-heated boiler and from the pressurized vessel. The gasification reactor is supported at its bottom end in the pressurized vessel at anchoring points. The convection-heated surface elements of the convection-heated boiler are supported by the quenching pipe and the boiler housing but in a stress-free manner.
    Type: Grant
    Filed: February 24, 1994
    Date of Patent: August 29, 1995
    Assignee: Krupp Koppers GmbH
    Inventors: Rainer Durrfeld, Johannes Kowoll, Eberhard Kuske, Hans Niermann, Gerhard Wilmer, Joachim Wolff
  • Patent number: 5431009
    Abstract: A duct for joining a higher velocity application to a lower velocity application such as a heat recovery vapor generator inlet duct apparatus for installation intermediate the exhaust of an associated gas turbine and an associated heat recovery vapor generation apparatus which includes a housing having an inlet and an outlet. The housing has the inlet and the outlet axially offset with respect to each other; and apparatus for directing fluid flow from the inlet to the outlet, the apparatus for directing fluid flow including at least one array of mutually parallel flat plates in stair step relationship extending substantially across the path of gases entering the inlet. In some forms of the invention the apparatus also includes a second array of mutually parallel flat plates in stair step relationship extending substantially across the path of gases exiting through the outlet.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: July 11, 1995
    Assignee: Combustion Engineering, Inc.
    Inventor: Wesley P. Bauver, II
  • Patent number: 5425415
    Abstract: A vertical heat exchanger including a vertical tube bundle connected between a lower inlet manifold and upper outlet manifold. The tube bundle comprises numerous pairs of concentric tubes with the inner tube being spaced from the outer tube to form an annular flow passage positioned around an inner flow passage. The inner tubes are welded between outer tube sheets that form a part of the upper and lower manifolds while the outer tubes are welded between inner tube sheets forming part of these manifolds. Each of the manifolds has a distributor ring which has radially directed openings throughout its periphery so as to provide for a radial flow in the manifold. Fluid enters the lower manifold through suitable inlet nozzles and exits the upper manifold through suitable outlet nozzles. A high temperature heating gas is directed up through the inner tubes of each pair of tubes by a conical inlet distributor and exits the upper end of the tube bundle through a similar conical distributor.
    Type: Grant
    Filed: June 15, 1993
    Date of Patent: June 20, 1995
    Assignee: ABB Lummus Crest Inc.
    Inventors: Bashir I. Master, Adrianus C. J. Jansen, Harry A. Wijnen Riems
  • Patent number: 5371918
    Abstract: A water heater for a carpet cleaning system has a first chamber and a main heat exchanger disposed within the first chamber, the main heat exchanger utilizing heat from a first source, preferably an engine, to heat water to be used in the carpet cleaning process. A second chamber substantially surrounds the first chamber and utilizes heat from a second source, preferably a blower in fluid communication with the carpet cleaning system's water tank. The second chamber substantially surrounds the first chamber to provide a thermal barrier between the first chamber and the ambient environment. The use of such a thermal barrier substantially reduces undesirable heat loss from the first chamber to the ambient environment and thus increases the efficiency of the water heater. A third chamber in fluid communication with the second chamber is heated by a second source and provides heat from the second source to the second chamber.
    Type: Grant
    Filed: May 5, 1993
    Date of Patent: December 13, 1994
    Inventor: William K. Shero
  • Patent number: 5369950
    Abstract: Method for operating a gas and steam turbine system without a feedwater tank, wherein heat contained in a pressure-relieved operating fluid of a gas turbine is utilized to produce steam for a steam turbine, includes the steps of preheating condensate flowing in a water-steam loop of the steam turbine; returning a first quantitative fraction of the preheated condensate in a loop for further preheating; and evaporating a second quantitative fraction of the preheated condensate; and a device for performing the foregoing method.
    Type: Grant
    Filed: August 10, 1993
    Date of Patent: December 6, 1994
    Assignee: Siemens Aktiengesellschaft
    Inventors: Hermann Bruckner, Erich Schmid
  • Patent number: 5370086
    Abstract: The present invention relates to a hot gas recovery boiler comprising a substantially horizontal gas inlet duct, a gas deflection duct connected to the inlet duct and opening out into a generally vertical enclosure that contains a set of superposed and substantially horizontal heat exchange stages plus a flue gas exhaust duct at the top of the enclosure. At least one heat exchanger is disposed in the proximity of the outlet of said inlet duct.
    Type: Grant
    Filed: November 24, 1993
    Date of Patent: December 6, 1994
    Assignee: Stein Industrie
    Inventors: Jean-Francois Saujet, Djamel Daoud
  • Patent number: 5365730
    Abstract: A combined gas and steam turbine system includes a steam turbine having a water/steam loop and a high-pressure stage in the water/steam loop. The high-pressure stage has a preheater and a high-pressure heater connected downstream of the preheater. A gas turbine has an exhaust gas side. A steam generator is connected downstream of the exhaust gas side of the gas turbine. The steam generator includes a firing system producing flue gases flowing in a given direction, the preheater, the high-pressure heater, an intermediate superheater connected downstream of the high-pressure stage, and a medium-pressure heater connected parallel to the high-pressure stage. The medium-pressure heater is disposed in the steam generator between the high-pressure heater and the preheater, as seen in the given flow direction of the flue gases.
    Type: Grant
    Filed: March 19, 1993
    Date of Patent: November 22, 1994
    Assignee: Siemens Aktiengesellschaft
    Inventors: Hermann Bruckner, Erich Schmid
  • Patent number: 5335628
    Abstract: A fuel cell and a boiler are coupled in such a manner that the water used to capture excess heat generated by the fuel cell is used for boiler feedwater heating. In one embodiment, steam generated by the boiler is used in an operation that converts the steam to condensate, and the condensate is returned to the fuel cell for use as a heat sink for the thermal energy generated within the fuel cell unit.
    Type: Grant
    Filed: September 3, 1993
    Date of Patent: August 9, 1994
    Assignee: Aqua-Chem, Inc.
    Inventor: William R. Dunbar
  • Patent number: 5326544
    Abstract: The heat from garbage upon incineration and solar heat can be effectively used to make sterilized hot water economically. A sterilized hot-water generator is provided with upper, intermediate and lower tanks in communication with each other. The lower tank includes a combustion chamber which is in communication with heating chambers housed centrally within the upper and intermediate tanks. A solar heat hot-water maker is attached to the front side of the sterilized hot-water generator. A sterilizer is located through the heating chambers in the upper and intermediate tanks to introduce the hot water in the upper tank into an associated sterilizing chamber for sterilization by heating. A fume removing tank is provided to dissolve, in water, fumes generated during combustion. Exhaust gases leaving the fume removing tank are fed to a reducing tank where they are reduced to oxygen, by plants, for example. The oxygen is then released into the atmosphere.
    Type: Grant
    Filed: November 12, 1991
    Date of Patent: July 5, 1994
    Assignee: Kabushiki Kaisha Oze
    Inventor: Yoshishige Takahashi
  • Patent number: RE36524
    Abstract: In a combined cycle system including a gas turbine, a steam turbine and a heat recovery steam generator (HRSG), wherein gas turbine exhaust gas is used in the heat recovery steam generator for heating steam for the steam turbine, the gas turbine exhaust gas flowing from an entry end to an exit end of the HRSG, and wherein the HRSG includes at least one high pressure evaporator arranged to supply steam to a superheater including multiple passes including a first pass at one end thereof adjacent the evaporator, and a final pass adjacent an opposite end thereof and adjacent the entry end of the heat recovery steam generator, and one or more intermediate passes between the first and final passes, the improvement comprising an attemperating conduit not exposed to the gas turbine exhaust gas, connecting the one end and the opposite end of the superheater, bypassing the intermediate passes to thereby introduce cooler superheated steam from the one end into the superheater at the opposite end.
    Type: Grant
    Filed: December 21, 1998
    Date of Patent: January 25, 2000
    Assignee: General Electric Co.
    Inventor: Leroy O. Tomlinson