Abstract: A fluidized bed combustion system for burning fuel particles, such as coal. The system includes a housing defining a first combustion region. An endless, flexible, perforate belt is shiftably mounted in the housing for supporting coal particles of relatively large size. A blower below the belt creates fluidized air which entrains smaller coal particles in a fluidized bed above the larger coal particles. The combustion gases arising due to combustion of the coal particles passes through a secondary combustion region in which coal fines are burned. The combustion gases continue upwardly through a scrubber in which limestone particles are entrained in the combustion gases to strip sulfides therefrom. The limestone particles are regenerated by a cyclone separator while the combustion gases travel through a passage containing boilers or other heat exchangers, whereby the heat from the combustion gases is transferred to fluids in the boilers.

Abstract: A coal and char burner (10) is formed of three concentric cylinders (14,16,18). The central passage (32) conveys char particles into the interior (20) of a coal gasifier. Fresh coal and secondary air enter the gasifier through concentric passageways (24,27) surrounding the central passageway (32). The coal and air form a high temperature reaction envelope (30) which surrounds the char stream (22) and rapidly heats the char particles.

Abstract: A reactor in which a plurality of vertical panels are disposed in a vessel and are constructed and arranged so as to form three combustion cells. Three of the panels each form a common wall between adjacent cells, and each cell is heated by a fluidized bed.

Abstract: A fluid bed combustor comprising a plurality of fluidized bed stages interconnected by downcomers providing controlled solids transfer from stage to stage. Each stage is formed from a number of heat transfer tubes carried by a multiapertured web which passes fluidizing air to upper stages. The combustor cross section is tapered inwardly from the middle towards the top and bottom ends. Sorbent materials, as well as non-volatile solid fuels, are added to the top stages of the combustor, and volatile solid fuels are added at an intermediate stage.

Abstract: A centrifugal spreader type feeder that supplies a mixture of particulate limestone and coal to the top of a fluidized bed reactor having a flow of air upward therethrough. Large particles of particulate matter are distributed over the upper surface of the bed to utilize the natural mixing within the bed, while fine particles are adapted to utilize an independent feeder that separates them from the large particles and injects them into the bed.

Abstract: An apparatus for feeding solids into the bed of a fluidized bed furnace (18). The feed solids are separated into a fine fraction and a coarse fraction. The coarse fraction is supplied to fluidized bed (16) in an in-bed pneumatic transport feed system or in an over-the-bed feed system. The fine fraction as well as fluidizing air are supplied to fines admission zone (24) wherein the fine fraction and fluidizing air are thoroughly mixed. The mixture of the fine fraction of feed solids and the fluidizing air is then passed upwardly through air distribution means (38) into fluidized bed (16).

Abstract: A combustion system and method for a coal-fired furnace in which a separator-nozzle assembly divides a coal-air mixture into a first stream containing most of the coal and a second stream containing a much smaller quantity of coal. Another nozzle is provided which receives another mixture of coal and air and discharges same in a combustion supporting relation to said streams. At start up and low loads, the separator-nozzle assembly discharges a majority of the coal and air in a combustion supporting relationship and the other nozzle discharges a relatively low quantity of coal and air. At high load conditions, the other nozzle discharges a majority of the coal and air while the coal and air discharging from the separator-nozzle assembly is kept at relatively low values. A splitter is provided for receiving a coal-air mixture from a mill and splitting it into two separate mixtures.

Abstract: A method of increasing the efficiency of a cyclone-fired boiler which uses high sodium lignite as fuel. The fuel produces ash deposits on heat transfer surfaces within the boilers, and in accordance with the method, powdered limestone is periodically injected into the firebox of the boiler in a quantity and for a time period such that the limestone is heated to a temperature in the range of from about 2200.degree. F. to about 2700.degree. F. and reacts with ash deposits in the boiler to form layers thereon. The layers so formed have a higher ash fusion temperature than the unreacted deposits and cause the resulting composite deposit to be more friable whereby the deposit can be removed using conventional soot blower apparatus.

Abstract: A direct fired system (10, 10') includes pulverizer means (14, 24) classifier means (12, 26, 28, 48, 76), burner means (16, 16') as well as a defined fluid flow path that serves to interconnect the pulverizer means (14, 24) and the classifier means (12, 26, 28, 48, 76) in fluid flow relation with the burner means (16, 16'). In accord with the mode of operation thereof, at the classifier means (12, 26, 28, 48, 76) a separation is had of the stream of the gaseous medium such that a portion of the gaseous medium is recirculated along with the oversize solid fuel particles back to the pulverizer means (14, 24) while the remainder of the gaseous medium is operative to convey the solid fuel particles that are of the desired size from the classifier means (12, 26, 28, 48, 76) to the burner means (16, 16') for burning, i.e., firing, in the latter.

Abstract: The invention comprises a steam generator having a circulating fluidized bed combustion system whereby there is provision to admit air flow incrementally along the gas path to control combustion rate and firing temperature in a manner to maintain differential temperatures along the gas path. The initial portion of the gas path where combustion is initiated can be held in one temperature range as 1550.degree. F. which is optimum for sulphur retention and the final portion of the combustion zone can be elevated in temperature as to 1800.degree. F. to produce a greater degree of heat transfer through the gas to fluid heat exchange surface downstream of the combustion zone.

Abstract: A fluidized-bed combustion system for a boiler, a heating furnace for heating steels or the like, in which a plurality of gas distribution pipes are disposed at the bottom of the combustion chamber. The lower end of each gas distribution pipe is communicated with an air supply line with an air flow rate control valve and a fuel supply line with a fuel flow rate control valve and the air and fuel admitted into the gas distribution pipe are mixed within the same and the air and fuel mixture is injected or sprayed into the fluidized bed through injection ports of the gas distribution pipe which are positioned adjacent to the bottom of the fluidized bed, whereby the complete combustion within the fluidized bed can be ensured and the combustion can be controlled over a wide range and optimized depending upon a load.

Abstract: A coal pulverizer is connected to the burner nozzles of a tangentially-fired furnace with conduits of varying lengths through which air-entrained coal is supplied for combustion within the furnace. An externally adjustable orifice assembly is mounted in each connecting conduit to equalize the flow of coal/air through the conduits to nozzles in the windboxes. Each orifice assembly comprises pivotable plates which move transverse the axis of the conduit to form an orifice in controlling the coal/air flow.

Abstract: A process and burner for the partial combustion of a finely divided solid fuel with oxygen.A core of oxygen-containing gas and an annulus of finely divided solid fuel surrounding said core are introduced into a reactor space via a burner. The solid fuel is centrally introduced into the burner, whereas oxygen-containing gas is separately introduced into the burner outside the central solid fuel. In the burner the solid fuel is caused to flow outwardly and the oxygen-containing gas is caused to flow inwardly for supplying the solid fuel as an annulus around the oxygen-containing gas into the reactor space.

Abstract: A method of operating a fast fluidized bed reactor according to the invention comprises: (1) providing a fluidized bed reactor having an upper and a lower region, the upper region having a cylindrical shape; (2) feeding matter to be reacted into the lower region of the reactor; (3) supplying a first stream of pressurized air to the reactor in the lower region at a velocity to fluidize the granular material in the circulating regime, a portion of the granular material is continually entrained into the upper region; (4) tangentially supplying a second stream of pressurized air to the upper region wherein, at maximum operating capacity for the reactor, the second stream of air constitutes in excess of about 50% of the total pressurized air fed to the reactor; (5) maintaining a Swirl number of at least about 0.

Abstract: The burner is formed of a tubular housing including a central tubular passage and a boundary annular passage for feeding into the gasification reactor under high speed a carburation medium such as oxygen or steam. At least three intermediate channels of coaxial annular sections are symmetrically arranged about the central channel and each communicates with a separate inlet conduit for feeding a mixture of powderized fuel with a carrier gas. The transition between the annular intermediate channel and the tubular inlet conduits is made such that the varying outline of the cross-section encloses the same area as the tubular inlet conduit or the annular section intermediate channel. The central tubular channel and the boundary annular channel for feeding the carburation fluid is configurated so as to divert one stream of the carburation fluid at an angle of about 45.degree. toward the axially directed jet of the powderized fuel mixture.

Abstract: A mill recirculation system (10, 40) includes pulverizer means (14, 48), classifier means (12, 44) and burner means (16, 68) as well as a preestablished fluid flow path by which the pulverizer means (14, 48) and the classifier means (12, 44) are interconnected in fluid flow relation with the burner means (16, 68). In accord with the mode of operation thereof, a separation is had at the classifier means (12, 44) of the stream of the gaseous medium such that a portion of the gaseous medium is recirculated along with the oversize solid fuel particles back to the pulverizer means (14, 48) while the remainder of the gaseous medium is operative to convey the solid fuel particles that are of the desired size from the classifier means (12, 44) to the burner means (16, 68) for burning, i.e., firing, in the latter.

Abstract: The invention comprises a dense pack heat exchanger for a steam generator having a circulating fluidized bed combustion system whereby a bed of solid particles comprising fuel and inert material is entrained in the furnace gas stream. Means are provided for collecting high temperature bed solid particles downstream of the furnace. The dense pack heat exchanger directs the hot collected particles down over heat transfer surface, such surface being a portion of the steam generator fluid circuits. Flow is induced by gravity means. The dense compaction of the solid particles around the fluid heat exchange circuits results in high heat transfer rates as the fluid cools the compacted solid material. The heat exchange surface is arranged to facilitate flow of the solid particles through the heat exchanger.

Abstract: The operation of gas turbines in combined cycle or cogeneration plants utilizing circulating fluidized beds is improved by increasing the temperature of the air supplied them. The temperature of bed solids circulating through an external heat exchanger is raised by combusting fuel in a combustion-augmenting zone through which the circulating solids pass. The gaseous products are combustion from that zone are introduced into the fluidized bed combustor. Thus the fluidized bed combustor operates at temperatures affording optimum sulfur removal by sulfur absorbing materials, the combustion-augmenting zone operates at an appreciably higher temperature to provide increased heat transfer to the compressed air for the gas turbine, and the off gases from the combustion-augmenting zone, which may be high in sulfur, are cooled in the combustor so as to bring about their desulfurization therein. Suitable apparatus is provided.

Abstract: A fluidized bed furnace (10) is provided having a perforate grate (9) within a housing which supports a bed of particulate material including some combustibles. The grate is divided into a plurality of segments (E2-E6, SH1-SH5, RH1-RH5), with the airflow to each segment being independently controlled. Some of the segments have evaporating surface imbedded in the particulate material above them, while other segments are below superheater surface or reheater surface. Some of the segments (E1, E7) have no surface above them, and there are ignitor combustors (32, 34) directed to fire into the segments, for fast startup of the furnace without causing damage to any heating surface.

Abstract: An apparatus for supplying stationary small- to medium-sized heating plant with flowable solid fuel such as coal dust or coal breeze has a vacuum conveyor running from a fuel storage container of the apparatus to the heating plant for transporting the fuel from the container to the boiler. The blower of the conveyor has an aspiration port joined up with the container. The container has flexible walls of textile material and has an air blow-off line and a filter sheet for separating the coal dust from any coal dust-air mixture produced. This design makes it possible for the heating plant to be run automatically with the least leakage of dust and volatile substances out into the air.

Abstract: The invention comprises a drying and sorting apparatus which is integrated with a conventional steam generator for separating organically derived solid fuel from solid inert materials and for removal of moisture from the solid fuel prior to feeding such fuel to a combustor. Low level heat in the steam generator combustion gases, after heat exchange with the steam generator fluid circuits, provides the means for removing moisture from the solid fuel when hot air/gas (unsaturated with respect to moisture) is passed through a bed containing a mixture of solid fuel and waste inert material particles, fluidizing them. When in a fluidized state the lighter organically derived solid fuel particles separate from the heavier inert material particles.

Abstract: A coal-air separator to be used in combination with a pulverized coal-fired burner having an elbow section and a wye section. The wye section is flow connected to the outlet of the elbow so that the coal-rich portion is transported through the main fuel conduit to the burner. The coal lean portion is transported through the take-off conduit, the outlet being positioned outside the furnace windbox.

Abstract: A system comprising a method and apparatus by which a double cone dispenser causes discharge of granular or particulate materials from a vessel at a uniform rate across the entire cross section of the vessel. In one form, the invention comprises a fluidized bed vessel which was a tramp removal and bed recirculation system associated therewith, which system comprises a novel dual cone apparatus at the bottom of the vessel.

Abstract: At least one movable nozzle (14) is mounted in an opening (18) in the wall of a fluidized bed reactor (22). Solid feed materials (62) in granular form are conveyed to the nozzle (14) and injected into the reactor (22). By changing the direction of the solids injection flow stream, the mixing, residence, and reaction characteristics of the reactor (22) may be controlled. The nozzle (14) is elongated and arranged so as to tilt on a horizontal axis (58), and may inject fresh material or recycled material previously removed from the bed reaction zone (34).

Abstract: Burner for use in a coal gasification process wherein a combustible mixture is formed comprising a combustion supporting gas such as oxygen, and a coal slurry. To avoid deposition of slag and ash particles along the hot, exposed face of the burner, a dynamic fluid blanket or barrier is directed transversely of the burner face. The fluid flow originates at the burner periphery and is addressed to sweep, or impinge against at least a part of the burner face adjacent to the central opening which defines the burner discharge port.

Abstract: The fluidized bed is situated in a combustion chamber formed from evaporator tubes welded in seal-tight relationship and leading into a gas flue. The combustion chamber is connected to the gas flue via two inclined connecting wall surfaces. Heater tubes bent into an L-shape extend through the fluidized bed. Each shorter limb of the heater tubes extends substantially vertically while the other longer limb extends substantially horizontally. The horizontal limbs pass through a substantially vertical combustion chamber wall at the level of the fluidized bed and the vertical limbs pass through the free surface of the fluidized bed beneath the connecting wall surface. As a result of this arrangement of the heater tubes, the stresses therein due to uneven thermal expansion of the heater tubes remain within permissible limits.

Abstract: Combustion air preheated to 550.degree. C. is forced into a suspension of wdered coal in water preheated to 100.degree. C. in a portion of a burner upstream of the burner orifice. Air passes into the preheated suspension through a porous wall separating the end portion of the air duct from the suspension duct, and its heat content is sufficient to vaporize the water of the suspension, while the amount of air flow is such as to provide approximately stoichiometric proportions of coal and air. Preheating is done by recuperators, through which the combustion product gases from the furnace flow before being discharged at a temperature low enough for evaporating condensed water.

Abstract: The invention comprises a steam generator having a circulating fluidized bed firing system. Particles of fuel and solid inert material are recirculated in a furnace wherein gas velocities are maintained at levels sufficient to entrain the fuel and inert material particles in the gas stream. A plenum is provided at the furnace outlet wherein gas velocity drops below entrainment level and the particles are directed to a collection hopper for recycle. The gas is withdrawn from the plenum through ducting in a manner to assure uniform gas distribution through the plenum. High gas velocity through the ducting improves heat transfer in the fluid cooled enclosure surface where such surface is incorporated into the ducting. The ducting connect to the downstream gas path.

Abstract: The invention comprises a steam generator fluidized bed which recirculates through a major portion of the normal gas to fluid heat transfer circuits. Solid bed material is separated, collected and recirculated. Bed temperatures are limited by regulation of density of bed inert material to inhibit the radiant aspects of combustion. Gas recirculation is used to supplement air flow to achieve higher than entrainment bed gas velocity in the fuel ignition and reaction zone. Fuel ignition and reaction are controlled by limiting the amount of atmospheric air flow to the circulating fuel rich bed mixture to regulate extent of propagation of the ignition and reaction zone into the initial portion of the circulating bed loop, starting from the point of highest gas pressure.

Abstract: The invention comprises a steam generator having a migrating fluidized bed combustor system. The bottom, head end of the bed incorporates a support floor system through which air is admitted tangential to the floor in a manner which causes the bed to migrate in a retraceable track. Tangential admission of air cools the floor and inhibits reverse flow down through the floor when the bed is slumped. Particle entrainment velocities are developed at mid-point in the bed. Tangential entrainment gas flow assures uniform distribution of combustibles and inert material throughout the lower bubbling bed and furnace area above the mid-point. Platens in the furnace zone straighten gas flow for gravity separation of particulate at the outlet of heat transfer surface above the furnace.

Abstract: An apparatus allowing the use of low-grade solid fuel powders (coal, lignite, peat) and products derived therefrom during cold starting periods and for backing up combustion chamber operation at low load. The pilot burner (1) has an auxiliary and pilot igniter which burns gas produced by gasifying low-grade fuel in a gasification unit (6) and a main igniter which burns the low-grade fuel powder in a storage silo (5). The combustion air is heated in an air heater (10) by the gas produced by gasifying low-grade fuel in gasification unit (6). In particular, turbulence is set up in the combustion air sent to the outlet of the pilot igniter. Application to combustion apparatus including steam generators of thermal power stations.

Abstract: A conventional pulverized coal-fired furnace is supplied fuel at two different levels. The raw coal is classified into a stream of relatively pure coal ground to conventional fineness for burners at the lower level, and a stream of very finely divided coal with a large, heavy mineral content for burners at the higher level.

Abstract: A fluidized bed reactor in which a grate is disposed in a housing for receiving a single bed of particulate material. The interior of the housing below the grate is divided into a plurality of zones and air is selectively passed through portions of the grate to fluidize corresponding portions of the bed above the zones. A plurality of air distributors are provided in the bed for reducing the height of the particulate material accumulating in various portions of the bed.

Abstract: A method of igniting a pulverized-coal annular burner flame having an internal back flow region, with the ignition energy being introduced centrally into the interior of the back flow region of the pulverized-coal annular burner flame. The ignition energy for the annular burner flame is furnished by an ignited pulverous fuel igniting flame or pilot light, which is operated with pulverous fuel having a different coarseness and/or consistency than does the primary fuel. The pulverous fuel, which is to be prepared for supplying a pulverous fuel pilot light, is withdrawn from the conduit of the primary fuel after an existing pulverizing plant. The pulverized fuel is withdrawn by means of a withdrawal device which is capable of being shut off, with the removal opening thereof being directed counter to the direction of the primary fuel flow.

Abstract: In a pulverized coal-fired steam generator having a generally vertical furnace (1) and a plurality of fuel-air admission assemblies (10) arrayed in a vertical windbox (40) in one or more walls of the furnace (1), at least one of the fuel-air admission assemblies (10) being a low load fuel-air admission assembly having a split coal bucket (30) with vertically adjustable upper and lower coal nozzles (32,34), the remaining assemblies having vertically adjustable single nozzle buckets (28), a tilt apparatus (50,60) for vertically adjusting all nozzles in unison in response to steam temperature at high loads and for vertically adjusting the lower coal nozzles of the split coal bucket of the low load fuel-air admission assembly independent of all remaining nozzles at low loads.

Abstract: A furnace (10) in which coal and cellulose fuel can both be burned on the same traveling grate (24). First means (36) are provided for introducing coal onto the grate at one end (38), such that it traverses the full grate run before it falls as ash from the other end (56) of the grate. Second means (48, 52) are provided for introducing cellulose fuel onto the grate at a central or middle location (54). Adjustable means (49, 50) are provided for varying the point at which the cellulose fuel is introduced onto the grate. If cellulose fuel having a relatively slow burning rate is being combusted, the adjustable means are set so as to introduce the fuel at a point on the grate further away from the discharge end. If cellulose fuel having a relatively fast burning rate is being combusted, the adjustable means are set so as to introduce the fuel at a point on the grate closer to the discharge end.

Abstract: When a pulverized coal-fired furnace is operating at low loads, the primary air and pulverized coal stream discharging from the coal delivery pipe is split into a first and a second coal-air stream and independently directed into the furnace by tilting at least one of the streams away from the other, thereby establishing an ignition stabilizing pocket in the locally low pressure zone created between the spread apart coal-air streams.

Abstract: A burner for introducing a suspension of solid fuel particles into a combustion chamber which includes a tubular conduit arranged to receive the suspension therethrough, and flow diverting means positioned at the discharge end of the conduit, and subdividing the cross section of the discharge end into a plurality of discharge openings. The burner may include a centrally disposed conduit which is coaxial with and surrounded by the tubular conduit, and an outer conduit surrounding the tubular conduit and coaxial therewith. The flow diverting means can be positioned at various positions between the respective conduits, to create a turbulent suspension of particles in the primary air stream, creating an aspirating effect for drawing secondary air into the burner along with the turbulent suspension of solid fuel particles.

Abstract: The method of operating a furnace including the steps of conveying (30) pulverized coal in an air stream towards a furnace (10), separating (34) the stream into two portions (36,38), one being a fuel rich portion (38), and the other being a fuel lean portion (36), introducing (40) the fuel rich portion into the furnace in a first zone, introducing (42,44) air into the first zone in a quantity insufficient to support complete combustion of all of the fuel in the fuel rich portion, introducing (46) the fuel lean portion into the furnace in a second zone, introducing (48) air into the second zone in a quantity such that there is excess air over that required for combustion of all of the fuel within the furnace, and introducing (50) lime into the furnace simultaneously with the fuel, so as to minimize the peak temperature within the furnace, and also minimize the formation of NO.sub.x and SO.sub.x in the combustion gases.

Abstract: A coal supply gun assembly for a fluidized bed combustor which includes heat exchange elements extending above the bed's distributor plate assembly and in which the gun's nozzles are disposed relative to the heat exchange elements to only discharge granular coal material between adjacent heat exchange elements and in a path which is substantially equidistant from adjacent heat exchange elements.

Abstract: It is an object of the invention to provide for a coal in oil mixture a combustor or burner system in which the ash resulting from burning the mixture is of submicron particle size.The burner system comprises, as shown in FIGS. 1 and 2, a burner section (11), a flame exit nozzle (12), a fuel nozzle section (13) and an air tube (14) by which preheated air is directed into burner section (11). Regulated air pressure is delivered to a fuel nozzle (34) in nozzle section (13) through a line (9). Means (8),(16), and (17),(29),(6),(30) and (31) are provided for directing a mixture of coal particles and oil from a drum (15) to a nozzle (34) of FIG. 2 at a desired rate and pressure while a means (19) returns excess fuel to the fuel drum (15). Means (25) is provided for keeping the coal particles uniformly distributed in the coal in oil mixture in fuel drum (15). Means (29), (30), and (31) provide for stable fuel pressure supply from fuel pump (8) to fuel nozzle (34).

Abstract: The outline of a tangentially-fired furnace combustion chamber is arranged to show a representative windbox in one corner of the furnace. The secondary air is disclosed as supplied through one set of vertically tiltable nozzles mounted in the windbox. The secondary air supply conduit is mounted to feed the tiltable nozzles. The secondary air supply conduit section adjacent to the nozzles has straightening vanes forming channels in which independently controlled louvers regulate the total cross-sectional area of the channels to maintain the desired velocity of the secondary air through the nozzles.

Abstract: The invention provides a means for more effectively adapting fluidized bed combustors for retrofit of existing boilers for burning of low grade inexpensive solid fuels. The operating discharge gas from a fluidized bed combustor is substantially lower in temperature from what exists at the furnace gas outlet of a conventional steam generator. Thus, outlet gas from fluidized bed combustors needs to be placed in the downstream gas path differently from conventional practice. The external combustors of the present invention permit placement of hot gas in the steam generator gas path where it can be effectively utilized. The invention also teaches how new steam generators can be configured advantageously to accommodate multiple fluidized bed combustors particularly as pertains to larger capacity steam generators in the 200 MW electrical and larger range.

Abstract: The invention is concerned to control the combustion conditions of a burner 1 supplied with a mixture of pulverized fuel and air. By use of a vortex amplifier 10 in the supply pipe 3, the supply of fuel is interrupted so that the flame is consequently first too lean and then too rich. The temperature of the burner flame is monitored by a photodiode device 6a and an indication is produced of the delay between the operation of the vortex amplifier 10 and the flame temperature passing through that indicating that the flame conditions are optimum. The length of the delay will indicate whether, and to what extent, the flame before the operation of the vortex amplifier was too lean or too rich. Adjacent burners can be controlled by operating the vortex amplifiers associated with each at different regular frequencies.

Abstract: A method of combustion of pulverized coal in two stages of combustion to reduce the amount of NOx produced by combustion. In a first stage, exhaust gas is added to air for combustion in a proportion of 35-60% of the air necessary for carrying out combustion. In a second stage, air for combustion is supplied in a proportion of 25-35% of the air necessary for carrying out combustion. In this method of combustion, the pulverized coal is combusted slowly at low temperature with the formation of a flame of low brightness to produce in large amounts activated intermediate components responsible for denitration reaction to promote reduction of produced NOx, and the concentration of CO produced can be reduced by abstaining from using the minimum air necessary for combustion.

Abstract: A solid fuel burner of the type having a cylindrical combustion chamber with a horizontal axis, in which the solid fuel is introduced tangentially into at one end, ignited, and moved spirally to the other end. The chamber is lined with fire resistant material. At least part of the bottom portion of the chamber has an opening therein for admitting a combustion-supporting gas into the chamber to both support combustion and fluidize the material being burnt. The openings are formed by spacing apart the fire-resistant lining of the chamber to define a plurality of slots through which the combustion-supporting gas is blown.

Abstract: In a fluidized bed plant for the combustion of impure solid fuel in the presence of an absorbent material which absorbs and neutralizes the impurities, in particular sulfur, the supply of absorbent material to the fluidized bed is controlled in dependence on the impurity content in the exhaust gases leaving the fluidized bed. To achieve a rapid control, at least part of the absorbent material is supplied to the fluidized bed in a finely ground state. The bed material may consist of coarse-grained absorbent material or a chemically inactive material, or a mixture of these. Coarse-grained absorbent material which is discharged from the fluidized bed can have its particle size reduced and be passed back to the fluidized bed.

Abstract: A pulverized coal-fired burner having a longitudinally elongated coal delivery pipe through which a stream of pulverized coal entrained in air is passed into the furnace and at least two air plenum chambers, one along the top and one along the bottom of the coal delivery pipe, connected in fluid communication with the interior of the coal delivery pipe at the discharge end thereof. A high pressure working fluid, such as air or flue gas, is passed through the plenum chambers into the coal delivery pipe so as to impinge against the coal-air stream passing therethrough thereby causing the coal-air stream to be deflected away from the longitudinal axis of the coal delivery pipe.

Abstract: A system for the fluidized reinjection of fine particles (carryover) into a fluidized bed combustor. The carryover recirculation system includes a fluidized reinjection bed which is fluidized using clean gas from the induced draft fan outlet boosted by a small auxiliary fan. The fluidized fine particles can be reinjected into the fluidized combustor bed by either dense phase transport or by dilute phase transport.

Abstract: A burner casing having a vertical support sleeve mounted at its center forms a combustion chamber below the sleeve and an annular duct space that surrounds the sleeve. A self supporting fuel cartridge containing consolidated solid fuel particles fits slidably within the support sleeve and has one end resting upon a mandrel located in the combustion chamber. Air to support steady state combustion of the fuel particles at a surface of the cartridge is forced downwardly through the cartridge. The heat of combustion and exhaust products pass from the combustion chamber through the annular duct space and then to other furnace components.