The Babcock & Wilcox Company

Babcock & Wilcox Power Generation Group, Inc.

Mcdermott Technology, Inc.

Blasch Precision Ceramics, Inc.

David J Walker

Felix Belin

Mikhail Maryamchik

Donald L Wietzke

David E James

Kiplin C Alexander

Michael J Szmania

Gary L Anderson

Paul S Knoebel

Sundara M Kavidass

David R Gibbs

Jeffrey J Bolebruch

Roger A Detzel

Edwin L Collins, Iii

Michael N Gold

Jeffrey Hahn

Detzel Roger A

John Arthur Fulmer

Richard F Romansky, Jr

A closed-cycle system and method of electrical power generation uses steam to transport charge carriers through an MHD generator. Water droplets, fine particles or mixtures thereof are used as the charge carriers. The fine particles are sufficiently small to allow the particles to pass through pumps and other equipment in the flow path with little or no damage, thereby eliminating the need to remove and re-inject a seed material, or treat it prior to discharge to the environment. The high operating temperatures of prior art MHD generators are avoided, thereby allowing more economical and readily available materials to be used. The system and method also allows the MHD generator to be used as the bottoming cycle in a single-loop power generation system, with a conventional steam turbine-generator used as the topping cycle, resulting in an increased heat rate with reduced emissions of greenhouse gases and other pollutants, and with reduced heat rejection to the environment per unit of electricity produced.

Closed-cycle MHD-faraday generation of electric power using steam as the gaseous medium

A system and method for quickly cooling and de-pressurizing a boiler arrangement in the event of a plant power loss, a.k.a. a black plant condition. A steam discharge system injects steam from the steam/water circuit into the furnace, thereby both cooling components of the boiler arrangement and reducing pressure in the steam/water circuit. This reduces or eliminates the additional cost associated with providing extra capacity in a steam drum and/or an independently powered boiler water pump. The system and method is particularly useful for quickly cooling the U-beams of a circulating fluidized bed (CFB) boiler during a black plant condition. In application to boiler arrangements with a selective non-catalytic reduction (SNCR) system employing steam as a carrier for a NOreducing agent, the steam discharge system advantageously uses the discharge nozzles of the SNCR system to inject the steam into the furnace.

Black plant steam furnace injection

An integrated fluidized bed ash cooler for a fluidized bed boiler, particularly a circulating fluidized bed (CFB) boiler, employs at least two fluidized bed sections positioned in series along a solids flow path. Each section contains fluidizing means, the first section along the solids path being separated from a following section with a threshold. The first section contains means for measuring a bed temperature in the vicinity of the fluidizing means and at a higher elevation within the fluidized bed. Means are provided for removing oversized bed material from the first section to facilitate the removal of ash while minimizing the possibility of ash plugging during operation.

Integrated fluidized bed ash cooler

An inert impingement surface that is pliable and which, when set in motion, works to shed itself of particle deposits. The pliable surface may be formed of a plurality of coactive members that co-operate with one another to clean-off the particle deposits from each other's surfaces. The coactive members may be in the form of chains, rods, cables, wires, granular inert materials such as gravel or metal balls or other impact means. The pliable surface may also be formed of a heat-resistant material which is caused to experience a continuing shape change, thereby casting-off the particle deposits adhering to the surface.

Wetted particle and droplet impingement surface

A bubble cap assembly for use in fluidized bed boilers, furnaces, or reactors, has a bubble cap, a stem, and at least one pin. One end of the stem is inserted into the bubble cap. The bubble cap has outlet holes for delivering a fluidizing medium, typically into a bed of granulated material, but which prevent backsifting of the granulated material into the bubble cap. The bubble cap also has at least one insertion hole, through which a pin may be inserted. When the pin is inserted through the bubble cap insertion hole, it also occupies a groove or indentation on the stem thereby preventing separation or disassembly of the bubble cap and stem combination. An elastic gasket may be provided between the bubble cap and stem to form a fluid tight connection.

Bubble cap assembly

A circulating fluidized bed (CFB) unit utilizing a mechanical dust collector located in a vertical flue above at least one heat exchange surface, and at least partially underneath the floor of a non-vertical flue, includes a plurality of individual collection elements each having a downward bottom outlet for a flow of cleaned gas conveyed through the collection elements.

Compact footprint CFB with mechanical dust collector

A collection element arrangement is provided having sleeve attachments near their lowermost ends which simulate a continuous sloping surface, or floor. The sleeve attachments upper surfaces forming the floor permit collected solids to flow down the sloping surface back into the furnace or reactor chamber. Stainless steel can be used for the collection elements and sleeve attachments since the floating floor accommodates differential thermal expansion between CFB components.

Floored impact-type solids separator using downward expanding separator elements

A circulating fluidized bed (CFB) boiler has one or more bubbling fluidized bed enclosures containing heating surfaces and located within a lower portion of the CFB boiler to provide a compact, efficient design with a reduced footprint area. The heating surfaces are provided within the bubbling fluidized bed located above a CFB grid and/or in a moving packed bed below the CFB grid inside the lower portion of the CFB boiler. Solids in the bubbling fluidized bed are maintained in a slow bubbling fluidized bed state by separately controlled fluidization gas supplies. Separately controlled fluidization gas is used to control bed level in the bubbling fluidized beds or to control the throughput of solids through the bubbling fluidized beds. Solids ejected from the bubbling fluidized beds can be returned directly into the surrounding CFB environment of the CFB boiler, or purged from the system for disposal or recycle back into the CFB. Solids which are recycled back to the CFB have less heat and can be used to control the temperature of the fast moving bed in the CFB.

CFB with controllable in-bed heat exchanger

Apparatus for separating solids from flue gas in a circulating fluidized bed (CFB) boiler includes plural vertical, impact type particle separators made of cooling tubes located within the CFB in a plurality of staggered rows. One embodiment employs a plurality of stacked, slip fit elements having apertures which accept the cooling tubes. The slip fit elements cooperate with one another to form a collecting channel, typically U-shaped, which separates particles from flue gases conveyed across the particle separators. Shiplap joints in between the individual slip fit elements prevent gas and solids from leaking therebetween and allow for thermal expansion. Alternatively, the impact type particle separators include cooling tubes connected to one another to form a unitary structure. Pin studs welded to the cooling tubes and covered with a coating of refractory; ceramic tiles; metal or ceramic spray coatings; metal or ceramic castings; weld overlay; and/or shields provide erosion resistance.

Cooled tubes arranged to form impact type particle separators

A tube wall, division wall, or wing wall section ( ) for a circulating fluidized bed boiler with improved erosion resistant characteristics has a reduced diameter tube section ( ) adjacent the refractory covered by an abrasion resistant refractory tile ( ). The refractory tile ( ) is mounted to the reduced diameter tube section ( ) with the upper edge of the refractory tile outside of or not extending beyond a solids fall line of solids in the fluidized bed to eliminate exposed discontinuities.

Wall protection from downward flowing solids

Apparatus for separating solids from flue gas in a circulating fluidized bed (CFB) boiler comprises plural vertical, impact type particle separators located within the CFB in a plurality of staggered rows. The impact type particle separators employ hung elements supported from fluid-cooled tubes which form a collecting channel, typically U-shaped, which separates particles from flue gases conveyed across the particle separators. By separating the support function from the collection shape required by functional performance considerations, the strength requirements of the material used to form the collection shape are reduced and the strength of the material from which the fluid-cooled support is made is much higher due to the lower operating temperature of the material comprising the fluid-cooled support, thereby permitting the use of lower cost materials.

CFB impact type particle collection elements attached to cooled supports

An apparatus for separating solids from flue gas in a circulating fluidized bed (CFB) boiler includes a plurality of impact type particle separators mounted vertically to a wall of the CFB. The impact type particle separators being adjacently positioned and horizontally spaced. Each impact type particle separator includes a plurality of vertically mounted cooling tubes connected to a fluid circulating system. A slip fit element surrounds the cooling tubes. A cup shaped configuration is formed by side walls and a back wall. The side walls and back wall have a plurality of separate vertically aligned segments extending along the height of the impact type particle separator. Each vertically aligned segment is connected at its ends to an adjacent segment.

Particulate collector channel with cooling inner elements in a CFB boiler

A CFB reactor or combustor having an impact type primary particle separator collects solids particles from a flow of flue gas/solids and returns the collected particles along an inclined or substantially horizontal planar floor to a bottom portion of the reactor or combustor for subsequent recirculation.

Circulating fluidized bed reactor with floored internal primary particle

A weldless connection system for U-beam particle separators is provided in which one end of each U-beam is provided with sides and a back that are separated from each other forming tabs. The tabs may be bent, or folded, about 90.degree. inward toward the channel formed by the U-beam. The back tab may be twice as long as the side tabs, and the extra half length of the tab can be folded about 180.degree. back at the back of the U-beam in a double thickness. Each tab has a hole therethrough. The double-length back tab has two holes; one hole is provided through each half. When the tabs are bent inward, the holes align. A bolt and washer placed through the aligned holes may be used to secure the tabs, and thus the U-beam, to a furnace roof structure. An alternate embodiment of the invention is provided in which only the sides of the U-beam form tabs which extend past the bottom of the U-beam.

Growing community of inventors

Wadsworth, OH, United States of America

David J Walker