A. Ahlstrom Corporation

Foster Wheeler Energia Oy

Hismelt Corporation Pty Limited

Ahlstrom Corporation

A. Alhstrom Corporation

A. Ahstrom Corporation

Timo Hyppanen

Juhani M Isaksson

Timo Eriksson

Steven J Provol

Ian D Webb

Ismo Nopanen

Teuvo Pulkkinen

Gregory J Hardie

John M Ganser

Matti A Hiltunen

Kurt Westerlund

Harry Ollila

Reijo J Kuivalainen

Kari Myohanen

Karl Myohanen

A method of and apparatus for controlling heat transfer in a fluidized bed reactor having a heat transfer chamber ( ) with a bed ( ) of solid particles therein, means ( ) for introducing fluidizing gas into the heat transfer chamber for fluidizing the bed of solid particles therein and heat transfer surfaces ( ) in contact with the bed of solid particles in the heat transfer chamber. Heat is transferred to said heat transfer surfaces from the solid particles. The fluidization of the bed of solid particles is varied according to a periodical function, e.g. by control means ( ) periodically varying the flow velocity of fluidizing gas being introduced into the heat transfer chamber. Thereby the instantaneous heat transfer, as well as, the effective heat transfer from solid particles to the heat transfer surfaces may be controlled.

Method and apparatus for controlling heat transfer from solids particles in a fluidized bed

Arrangement in a wall and a method of coating a wall

Solid particles are transported from a first chamber (e.g. combustion chamber of a fluidized bed reactor) to an adjacent second chamber (e.g. a transporting and/or processing chamber) by providing a solid flow gas seal, a controllable solid flow valve, or both in a partition between the chambers. Transporting gas is introduced into the first chamber to transport solid particles as multiple solid flows from the first chamber to the second chamber. A number of narrow passages in the partition wall disposed one on top of the other, and having a height to length ratio of less than 0.5, less than 50 mm, act as the gas seal and controllable solid flow valve in the partition. The transporting gas may be introduced through the bottom of the first chamber, a side wall opposite to the partition wall, or both, and the partition wall may be lined with refractory adjacent the first chamber with passages in the refractory lining being made of combustible material which is burned away during heating of the refractory lining. The passages may also slant upwardly slightly from the first chamber to the second chamber, e.g. about 15 degrees.

Method and apparatus for transporting solid particles from one chamber

A method and apparatus for recovering heat from solid particles in a fluidized bed reactor, utilize a heat transfer chamber, having heat transfer surfaces disposed therein. Hot solid particles are continuously fed into the heat transfer chamber and gas is introduced into and discharged from the heat transfer chamber. Gas is introduced into the heat transfer chamber for controlling the flow of solid particles therein. The heat transfer chamber is divided into at least one heat transfer zone and at least one solid particle transport zone, by providing more heat transfer surfaces in the heat transfer zones (e.g. 90% or more of the total heat transfer area) than in the solid particle transport zones. The heat transfer is controlled by introducing separately controlled flows of gas into the heat transfer zones and the solid particle transport zones.

Method and apparatus for recovering heat in a fluidized bed reactor

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.

Method and apparatus for treating hot gases

A centrifugal separator has a plurality of substantially planar walls, including a first wall, defining a vortex chamber having an interior gas volume and for establishing at least one gas vortex in the gas volume, and the gas volume has a cross section that is distinctly non-circular, (and preferably quadrate). In addition to conventional outlets the separator includes a gas inlet having at least one elongated jet-defining wall with a free end portion extending into the gas volume a first distance from the first wall, to define a gas jet that extends substantially tangentially to the gas vortex in the gas volume. An insert extends between the jet-defining wall free end portion and the first wall and defines a gas flow direction changing surface. The insert may be substantially solid refractory material, or include a number of cooling fluids circulating tubes, and a gas flow direction changing surface may be substantially planar or curved. The first distance is typically at least 50 mm, but less than 25% of the dimension of the wall perpendicular to the first wall. The jet defining wall and the gas direction changing surface may make an angle .alpha. between 20.degree.-80.degree. and the first distance may be between 0.2-5 times the width of the gas inlet. The height of the gas inlet is at least twice as great as its width.

Centrifugal separator assembly and method for separating particles from

The present invention relates to a combined cycle power plant comprising a air compressor providing pressurized air at pressure greater than 2 bar; a gas turbine means for driving the gas compressor means; a pressure vessel, circular in cross-section, connected to said air compressor and being capable of withstanding pressures greater than 2 bar; a pressurized circulating fluidized bed reactor enclosed by the pressure vessel, the circulating fluidized bed reactor having a reactor chamber, including substantially planar steam generation tube walls having a bottom section; means for leading hot combustion gases away from said reactor; one or more non-circular centrifugal separator(s) disposed within said pressure vessel being adapted to the reactor chamber and internal pressure vessel geometry for receiving and purifying hot combustion gases, having a gas outlet leading from said separator out of said pressure vessel; said centrifugal separator comprising a vertical vortex chamber having distinctly planar steam generation tube walls defining an interior gas space; and a bubbling fluidized bed heat exchanger chamber having distinctly planar steam generation tube walls defining an interior of said chamber, said chamber being connected to the bottom section of said reactor chamber; a heat recovery unit adapted to the gas turbine means for recovering heat from gas discharged therefrom; a steam generation cycle having a steam turbine, steam generation surfaces including said steam generation walls, and steam superheating surfaces.

Combined cycle power plant with circulating fluidized bed reactor

Method and apparatus for providing a gas seal in a return duct and/or

Particles in a fluidized bed reactor (e.g. a circulating fluidized bed reactor) are discharged from the reactor chamber and then cooled (heat is recovered from them) in a processing chamber. This is accomplished in a particularly advantageous way by discharging the particles from the reactor chamber at a first level (e.g. through a non-mechanical seal or a classifying wall) into a lifting chamber. Upwardly flowing gas in the lifting chamber entrains the particles and lifts them into the processing chamber. After processing, the particles in the processing chamber are returned to the reactor chamber at level higher than the first level, at which point the pressure in the processing chamber is higher than the pressure in the reactor chamber. The particles may be classified in the lifting chamber by utilizing fluidizing gas to transport solid particles smaller than a predetermined size to the processing chamber while discharging larger particles from the bottom of the lifting chamber.

Method and apparatus for processing bed material in fluidized bed

A fluidized bed reactor system includes a reaction chamber comprising a circulating (fast) fluidized bed, with a first grid for the introduction of fluidizing gas, and a bubbling (slow) fluidized bed having a second grid for introduction of fluidizing gas. The second grid is mounted below the first grid. First and second interconnections are provided between the circulating and bubbling beds. Particles flow from the circulating bed through the first interconnection to the bubbling bed, and vice versa for the second connection. The interconnections are positioned with respect to each other so that the pressure and density conditions within the beds are the sole mechanisms that provide the driving force to control the flow of particles from the circulating bed to the bubbling bed. An indirect heat exchanger is located in the bubbling bed for cooling particles, and various constructions of partitions may be provided for dividing up the bubbling bed and defining the interconnections, the system and method provided being greatly simplified compared to prior art constructions.

fluidized bed reactor and method of operation thereof

A circulating fluidized bed reactor has substantially vertical walls with cooling elements, defining the interior of the reactor chamber, and a device for introducing fluidization gas at the bottom of the fluidized bed reactor. Particulate material is introduced into the reactor. A separator separates particulate material from the exhaust gases, the separator being in connection with the reactor chamber. A return duct is connected to the separator. A bubbling fluidized bed is adjacent the reactor and provided with a heat exchanger for cooling particulate material, and side walls, rear and front walls having cooling elements in fluid communication with the cooling elements of the reactor chamber; and a discharge channel with a separate fluidizing gas source for discharging particles from the bottom of the bubbling bed to adjacent the top of the bubbling bed in the reactor chamber. A method of operating a circulating fluidized bed reactor, comprises the steps of maintaining a circulating fluidized bed in the reactor; separating particulate material from the gas in the separator and returning separated material back to the reactor; introducing particulate material into the bubbling fluidized bed above the upper surface of the bubbling fluidized bed; fluidizing the particulate material in the bubbling fluidized bed and recovering heat from the fluidized particulate material by the heat exchanger; discharging cooled particulate material from the bubbling fluidized bed at its lower section into the lower section of the discharge channel; fluidizing the discharged particulate material in the discharge channel; and introducing particulate material from the upper section of the discharge channel into the reactor chamber.

Circulating fluidized bed reactor and method of operating the same

A fluidized bed assembly, such as an ash cooler, includes first and second fluidized bed chambers each having a bottom portion and side walls. Fluidizing gas is introduced into the bottom portions to fluidize particulates within the chambers. A flow equalizer (such as a barrier having a number of openings associated with it) separates the chambers and provides a substantial uniform flow of particulates from the first chamber to the second chamber so that no dead spots or corners form in the chambers adjacent the flow equalizer. Heat exchanger components are typically provided in the barrier for circulating heat exchange fluid through the barrier. Also, heat exchangers are provided in one or both of the chambers to cool the particulates. The particulates mix in the second chamber, and after cooling may be recirculated to a gasifier/combustor for supplying ash to the first chamber. A classifier chamber is connected between the reactor and the first chamber. Fluidizing gas may be returned from the chambers to the reactor.

Fluidized bed assembly with flow equalization

A method and apparatus for cooling hot gas in a reactor in which the lower section of the reactor is provided with an inlet for hot gas and a chamber encompassing a bubbling fluidized bed. A central section of the reactor is provided with a riser, and the upper section with a gas outlet, and the reactor has heat transfer surfaces for recovering heat from solid particles. The riser is defined by vertical walls which are disposed above the bubbling fluidized bed so that they divide the fluidized bed into concentric outer and inner parts. From the inner part of the fluidized bed solid particles are supplied to the hot inlet gas for cooling thereof. The gas containing solid particles is conveyed through the riser into the upper section of the reactor, where solid particles are separated from the gas in a particle separator and returned to the fluidized bed into the outer part thereof.

Apparatus for treating or utilizing a hot gas flow

A fluidized bed reactor system, including a reactor chamber defined by a wall structure formed by a plurality of tubes through which a heat transfer medium circulates, is constructed so as to provide numerous advantages over conventional constructions. A fast fluidized bed of solid material is established in the reactor chamber. A solid material processing chamber is disposed adjacent the reactor chamber on the outer side of a wall structure defining the reactor chamber, e.g. for recovering heat from the solid material. The processing chamber shares a common wall portion with the reactor chamber and a slow fluidized bed of solid material is provided in the processing chamber. Particle passage openings are provided in the common wall. Particles from the processing chamber are recirculated to the reactor chamber after treatment (typically cooling). A robust common wall structure is provided between the processing chamber and the reactor chamber, which has adequate open area for circulation of particles into the processing chamber, yet can substantially solely support the processing chamber.

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Karhula, Finland

Timo Hyppanen