Abstract: A fluidized bed combustion system particularly suitable for use in a residential heating system comprising a fluidized bed combustor housing a combustion chamber wherein crushed fuel is burned to generate hot flue gas, a heat exchanger disposed outside of the combustor in the flow path of the flue gas, a particulate collector for removing fine particles entrained in the flue gas before the flue gas is vented to the atmosphere, and an induced draft fan for venting the flue gas to the atmosphere and drawing fluidizing air and recirculated flue gas through the combustion chamber. The combustor is uncooled and heavily insulated so as to provide a substantially adiabatic combustion chamber therein in order to minimize heat loss therefrom. Electric heating means are disposed within the fluidizing region of the combustion chamber to provide the capability of heating the slumped bed during shutdown to maintain bed temperature above the ignition point.

Abstract: The invention relates to the method and equipment for treatment of fuel for fluidized bed combustion, which includes drying, classification and crushing of the fuel. The method for treatment of fuel comprises mixing the fuel with hot ash removed from the fluidized bed combustor and drying said mixture in a fluidized bed dryer in which the velocity of the fluidization fluid equals or is lower than the minimum fluidization velocity of particles in the fluidized bed combustor. The equipment for treatment of fuel comprises a bunker, crusher and dryer, comprising a fluidized bed dryer provided with appropriate piping for interconnection of the fluidized bed dryer, fluidized bed combustor, fuel bunker and crusher.

Abstract: A method is provided for improving the sulfur capture potential of lime in the fluidized bed combustion of coal and for improving the flow characteristics of the feed coal therefor comprising collecting partially sulfated limestone particles from the fly ash of the flue gas from the fluidized bed combustor, and (a) retaining said particles in the flue gas stream, thereby hydrating said particles, and returning said particles to the combustor; or (b) mixing said partially sulfated limestone particles with wet coal thereby drying said coal and simultaneously hydrating unreacted calcium oxide to form calcium hydroxide, and recycling said mixture of dry crushed coal and calcium hydroxide into said fluidized bed combustor; or (c) introducing wet coal in the flue gas upstream from said collected particles, thereby providing moisture to hydrate said particles, and returning said hydrated particles to the combustor.

Abstract: An incinerator for combusting sludge or the like is supplied with combustion air which is mixed with 5-40% by weight of a high-humidity, low-oxygen-concentration gas for adjustment of the excess ratio of combustion air and control over burning of nitrogen oxides in the incinerator. The gas is supplied from a predrier for drying the sludge or comprises a gas discharged from the incinerator.

Abstract: A boiler comprising a furnace box, having a peripheral wall, from which products of combustion pass to a smoke box wherein the furnace box comprises a lower compartment, means to establish a fluidized bed in the lower compartment, an upper compartment, an exit connected to said upper compartment for passage of products of combustion from said furnace box, means to isolate said lower compartment from said exit except by communication through said upper compartment and through a foraminous element located in the path of the products of combustion from said lower compartment to said upper compartment.

Abstract: A fluidized bed apparatus and a process for the gasification of combustible materials such as biomass heavy hydrocarbon oils and coal. Two or more separate reaction zones connected in series as a closed loop are formed within a tubular housing, through which a bed of particulate heat transfer medium such as sand continuously and successively recirculates while being maintained in the fluidized state. One of the reaction zones serves as a cracking zone for the combustible material and another one of the reaction zones serves as a heat-up zone for thermally regenerating the heat transfer medium by partial or complete combustion of char produced in the cracking zone.

Abstract: A combustor grid for use in an incinerator having air bars for distribution of fluidizing air. Air is distributed from a source of pressurized air to a configuration of air bars in fluid communication with each other. Each air bar in the grid has an upper surface with air injection ports and side walls which converge toward the bottom surface. The air injectors may be refractory covered metal tubes on a conduit or individual air nozzles.

Abstract: A fluidized bed combustor having a distributor plate assembly including an inverted frustopyramidal surface with slots and offset shields thereover to form laterally oriented air flow openings into the combustion chamber from a first plenum for debris particle classification along said surface. At the bottom of each frustopyramidal surface is an outlet for classified debris. Air flow riser tubes project up from a second plenum to a position above said surface. Forced air is supplied to the slots and the risers, with means to regulate relative flow to them.Projecting down from the debris outlets are drop tubes having cooling fins, such tubes connecting to inlets of an auger conveyor. The auger conveyor has a coolant-cooled housing and a coolant-cooled auger.

Abstract: Method and furnace for the incineration of combustible material and the generation of hot gas, the furnace comprising a lower chamber provided with an inlet for air and an inlet for combustible material and an upper chamber provided with an inlet for air and a stack which chambers are communicated with each other inside the furnace, and the method comprising blowing air and combustible material into the lower chamber of the furnace in a direction tangential to the wall of the lower chamber and blowing air into the upper chamber of the furnace in a direction tangential to the wall of the upper chamber for thereby generating hot gas in the upper chamber.

Abstract: A method and apparatus for controlling steam production by controlling the flow rate of particulate solids from a fluidized bed combustion chamber through a vertical heat exchanger. The pressure drop across a section of the vertical heat exchanger is monitored and compared with a set point pressure drop. When the pressure drop being monitored falls below the set point pressure drop, a signal is provided to a particulate solids feed control means which then allows more particulate solids to be circulated through the vertical heat exchanger. The vertical heat exchanger receives heat from the particulate solids. The additional amount of particulate solids fed to the vertical heat exchanger are recirculated along with the previous amount of particulate solids through the heat exchanger into the fluidized bed combustion chamber. Because of the additional cooled particulate solids in the fluidized bed combustion chamber the temperature of the fluidized bed combustion chamber drops.

Abstract: This invention relates to a fluidized bed for use in heat treating articles, the bed having a container for containing a mass of refractory particles. The container has a porous base and a supply pipe for supplying a fluidizing gas to the underside of the porous base from which the gas will flow through the porous base and into the mass of refractory particles. The fluidizing gas flows through an adjustable control valve arranged in the supply pipe. There are also provided at vertically spaced positions above the upper surface of the porous base a pair of temperature transducers which are connected together to provide a signal which is dependent upon the difference in the temperatures at the vertically spaced positions, there being also provided power actuated means in the form of an electric motor which in use is arranged to receive the signal from the temperature transducers and then actuate the adjustable valve in accordance with the signal received.

Abstract: A fluidized bed furnace (10) for generating steam (26) is designed to operate over a given load range, for example from 50% of full load to maximum capacity rating (MCR). The air distributor (12) is designed with a constant pressure drop restriction means or "float" (36) in each air inlet (18). As the load varies, the pressure drop across the float (36) will remain constant, reducing the overall fan horse power requirements.

Abstract: A plate grid, and a fluidized bed reactor incorporating the plate grid, are disclosed. The plate grid includes air distribution apertures for delivering pressurized air to the reactor, and conduits for removing refuse, such as tramp material and/or agglomerated material, from the fluidized bed. The conduits include downwardly diverging walls extending from the lower face of the plate grid support surface. The fluidized bed reactor incorporating the plate grid further includes a chamber located below the plate grid support surface in communication at its upper end with both the air distribution apertures and conduits and at its lower end with a discharge port. The method of operating the fluidized bed reactor includes filling the reactor, and consequently the chamber and conduits, with granular material to form a space between the top surface of the granular material in the chamber and the lower face of the support surface.

Abstract: A fluidized bed combustor comprises a housing having a chamber therein with a top having a discharge for the gases which are generated in the chamber and a bottom with a discharge for heated fluid. An assembly is arranged in the lower portion of the chamber and the assembly includes a lower plate which is mounted on a support flange of the housing so that it is spaced from the bottom of the chamber and defines a fluid plenum between it and the bottom of the chamber for the discharge of heated fluid. The assembly includes a heat exchanger inlet plenum having tubes therethrough for the passage of fluidizer air and a windbox above the heat exchanger plenum which has a distributor plate top wall. A portion of the chamber above the top wall defines a fluidized bed.

Abstract: An arrangement for the burning of materials having components that are difficult to burn out and which tend to be adhesive upon heating. A turbulent layer is formed and connected with a combustion chamber for burning the materials. Combustion air is distributed to the turbulent layer and the combustion chamber for removing a portion of heat that is released, so that the combustion chamber retains a minimum temperature above a predetermined level. A contact chamber is connected to the turbulent layer and communicates with the combustion chamber. A constricting collar is provided with nozzles for applying combustion air.

Abstract: A bed support, and a fluidized bed reactor incorporating the bed support, the bed support including a conical-shaped support with downwardly converging surfaces terminating in a conduit for removing tramp material and/or agglomerated material from the reactor. The downwardly converging surfaces have main air source nozzles for directing pressurized air parallel to and downwardly along the downwardly converging surfaces toward the conduit. In a first embodiment, the conduit has downwardly diverging walls. In a second embodiment, the conical-shaped support further includes an inverted cone positioned over the conduit, the inverted cone having central air source nozzles and slots in the lower portion of the cone. In a third embodiment, the conical-shaped support further includes a bar grate having central air source nozzles positioned within the conduit.

Abstract: A fluidized bed reactor e.g. for the burning of fuels of different calorific values. The bottom part of the combustion chamber is divided into an outer and an inner fluidization zone by a partition wall adjacent to the distributor plate. Heat transfer surfaces are disposed in the outer fluidization zone. Heat can be withdrawn from the outer fluidization zone which is activated when burning fuel having a high calorific value. When burning fuel of lower calorific value the outer fluidization zone is not operated. The inner fluidization zone will be in operation in both cases. The supply of fluidizing gas to the second fluidization zone is controlled in order to maintain predetermined conditions in this zone.

Abstract: A fluidized bed call (10) having a static ignition bed (18) of inert heat storage particles (50) disposed immediately beneath and adjacent to a fluidizing region (44) wherein fuel particles are combusted, characterized in that the heat storage particles (50) are generally spherical in shape, each particle having a plurality of protuberances (52) extending outwardly from the surface of the particle a preselected length thereby maintaining a minimum spacing, equal to the preselected length of the protuberances, between neighboring spherical particles within the static ignition bed thereby ensuring that sufficient void space (54) exists within the static ignition bed for the fluidizing air to flow upward through the static ignition bed into the fluidizing region without an excessive pressure drop and for the fuel particles to laterally penetrate the static ignition bed.

Abstract: Apparatus and methods for fluidized bed incineration of waste containing phosphorus wherein the bed comprises lime or limestone which negates heretofore existing problems incident to the presence of phosphorus.

Abstract: A process and pressurized, gasification reactor apparatus for converting combustible carbon containing materials such as coal char and other carbonaceous solids or carbonaceous solids/heavy oil combinations to an intermediate heating value fuel gas. The gasification reactor includes an insulated fluidized bed reactor chamber, an upper reactor housing for a freely suspended bayonet bundle type heat exchanger for (a) superheating incoming saturated steam and (b) cooling outgoing high temperature product gas, and a lower reactor housing structure which includes a free-floating, conically-shaped perforated plenum chamber. The superheated steam and oxygen are premixed with the plenum chamber before being pressure directed into the fluidized bed reactor chamber for mixture and combustion with the incoming combustible carbon containing materials such as coal char. After reaction of the superheated steam, oxygen and coal char in the fluidized bed reactor at temperatures ranging from 900.degree. F. to 1750.degree. F.

Abstract: A loose fitting movable cover plate (36), suitable for the severe service encountered in a fluidized bed combustor (10), restricts the flow of solids into the combustor drain lines (30) during shutdown of the bed. This cover makes it possible to empty spent solids from the bed drain lines which would otherwise plug the piping between the drain and the downstream metering device. This enables use of multiple drain lines each with a separate metering device for the control of solids flow rate.

Abstract: A fluidized-bed system for feeding coal or a coal-limestone mixture into a fluidized bed combustor, a perforated horizontal distributor plate dividing the chamber into upper and lower chamber sections, means for feeding solid fuel particles into the upper chamber section, a source of high velocity gas connected to the lower chamber section and passing through the plate into the upper chamber section for entraining the particles, means for heating the high velocity gas before it is introduced into the upper chamber, an entrainment section defined by converging upper sides of said fuel feeding chamber, and a stream splitting section disposed above said entrainment section and connected to a plurality of pneumatic transport lines each penetrating the distributor plate of a fluidized bed combustor and terminating in an outlet feedport.

Abstract: A fluidized bed boiler system and a manner of operating the same is provided wherein a fluidized particulate bed in which solids are not recycled is utilized. High temperature flue gas is directed to a boiler means. A portion of both the high temperature and a low temperature gas stream are recycled to a fluidizing gas stream for fluidizing the particulate bed.

Abstract: In the method of feeding pulverized solid fuels into a fluidized bed hearth, the granular solid fuel is first delivered into a fuel distributing space where it is fluidized by means of a whirling stream of air and the fine granular components of the fluidized fuel are pneumatically fed through an array of feeding pipes into the fluidized bed formed in the combustion space of the hearth. The device for performing the method includes heat-resistant feeding pipes uniformly distributed between the combustion space and projecting into the fuel distributing space to immerse into the fuel distributing fluidized bed of fuel. The fluidizing air of stream is introduced into the distributing chamber to act both as the fuel conveying medium and as a combustion air in the combustion space.

Abstract: Apparatus and methods for fluidized bed incineration of waste containing phosphorus wherein the bed comprises lime or limestone which negates heretofore existing problems incident to the presence of phosphorus.

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 pipes are provided in the bed for receiving excess particulate material accumulating in various portions of the bed and for blowing air into said latter portion, to reduce the build-up of particulate material in the bed.

Abstract: A fluidizable bed apparatus comprises a container containing a bed of fluidizable particulate material which becomes hot in use. The apparatus is characterized in that it includes at least one passage for the flow of cooling medium therethrough arranged beneath a bottom wall of the container. The or each passage has communicating therewith at least one inlet, preferably arranged beneath the bottom wall, and at least one outlet, preferably arranged adjacent side walls of the container. Nozzles for supplying fluidizing medium to the container for fluidizing the bed are arranged to pass through the bottom wall of the container.

Abstract: A fluidized bed combustor having in its distributor plate assembly at the bottom of the combustion chamber, air outlets in the distributor plate surface, air flow riser tubes projecting above said surface, light liquid fuel nozzles located adjacent certain of the riser tubes for injection of liquid fuel into the air forcefully flowing up these riser tubes, and the share of air flowing through the riser tubes relative to the share of air flowing through the outlets being controlled by regulating means.

Abstract: A fluidized bed combustion device adapted for use with a boiler has an air distributor consisting of a row of generally horizontally oriented, apertured sparge pipes or tubes disposed in a bed of inert particulate material. The center pipes in the row are connected to a start-up burner for receiving heated combustion products and excess air and the outer pipes in the row are connected to selectively receive air through a separate delivery path. During start-up and low load conditions, only the center pipes are pressurized and so that only the center portion of the bed is fluidized to minimize the heat input requirements. Once the central portion of the bed has been heated to the required temperature, primary fuel is delivered to sustain combustion without the start-up burner. At the completion of the start-up process and during high fire conditions all of the tubes are pressurized to fluidize the entire bed.

Abstract: A vapor generating system in which a furnace section is provided that is formed by four upright walls, the lower portion of two opposed walls being slanted inwardly to form a hopper portion. A plurality of openings are formed in each of the opposed walls immediately above its slanted portion. Two gasifiers extend adjacent said opposed wall portions, respectively, and surround the respective slanted wall portions and openings, so that the respective interiors of the gasifiers communicate with the openings. A bed of adsorbent material is supported in each gasifier for adsorbing the sulfur generated as a result of the gasification of fuel introduced into the gasifier and air is passed through the bed of adsorbent material to fluidize said material so that, upon combustion of said fuel, a substantially sulfur-free product gas is produced which passes from the gasifier, through the openings and into the furnace section.

Abstract: A method for safely and continuously pyrolyzing organic material such as contained in municipal waste is presented for use in a two-bed pyrolysis system primarily comprising a pyrolysis reactor and combustion reactor in which several different physical factors influencing the state of fluidization such as amount of sand in the system, circulation rate of the sand, pressure difference between the free boards of the two reactors and superficial velocity in the pyrolysis reactor, are comprehensively controlled or regulated so as to maintain the operating point of the system at substantially the center of the stable operating range. The feed rate of material charged into the system may also be regulated as required.

Abstract: Heat exchanger for gases, comprising a vertical shaft with upward flow of gas between rows of staggered horizontally disposed sets of tubes, downwardly restricted by a gas penetrable bottom (2) and upwardly by the uppermost set of tubes, and over its entire vertical length containing a granular material (7) which is kept in motion by the essentially vertically upward gas stream. The heat exchanger is characterized therein that the ratio between the diagonal free opening a and the horizontal free opening b between the tubes (4) in the set of tubes lies within the range 0.45:1-0.9:1 for controlling and restricting the vertical movement of the grains in the heat exchanger, thereby obtaining an approximately continuous temperature gradient in the gas-grain mixture over the entire height of the heat exchanger.

Abstract: A fluidized bed combustion device adapted for use with a boiler has an air distributor consisting of a plurality of rows of generally horizontally oriented, apertured sparge pipes disposed in a bed of inert particulate material. The rows of pipes are vertically spaced apart with the upper row being connected to a start-up burner for receiving heated combustion products and excess air and the lower rows of pipes are connected to selectively receive air or inert gases through a separate delivery path. During start-up and low load conditions, only the upper row of pipes is pressurized and so that only the upper portion of the bed is fluidized to minimize the heat input requirements. Once the upper portion of the bed has been heated to the required temperature, primary fuel is delivered to sustain combustion without the start-up burner. At the completion of the start-up process and during high fire conditions all of the rows of tubes are pressurized to provide a deeper bed of fluidized material.

Abstract: A system for the comminution of coal, slurry formation and feed of the coal slurry to a fluidized bed reactor.

Abstract: A method of operating an adiabatic fluidized bed reactor, and an adiabatic fluidized bed reactor, including the step of providing pressurized air to an adiabatic fluidized bed reactor both through openings located in a support surface and through openings located in the reactor walls having outlets below the surface of the bed of granular material. The structure of the adiabatic fluidized bed reactor includes support surface air distribution nozzles extending through a support surface, reactor wall air distribution openings extending through the reactor walls having outlets below the surface of the bed of granular material, and separate control valves for controlling the flow of pressurized air to the support surface air distribution nozzles and to the reactor wall air distribution openings. The method and apparatus of the present invention result in higher reactor hydrodynamic turndown ratios than can be achieved with conventional single-bed reactors. For example, a hydrodynamic turndown ratio of 6.

Abstract: A fluidized bed furnace having a vessel with cooled or insulated walls and an inflow plate. A fluidized bed of inert material is maintained by air nozzles in the inflow plate and heated to the ignition temperature of coal. Pressure pipes deliver the coal and, if appropriate, additives such as lime, into the vessel below the upper boundary of the fluidized bed for combustion.

Abstract: A fluid bed heater or vaporizer unit has a generally cylindrical configuration with its major axis horizontally disposed. A mixture of coal and limestone is fed into the elongated fluidized bed within the unit for combustion; the limestone being present to minimize sulfur emissions due to the sulfur present in the coal. The wall of the unit in the region of the freeboard is lined with horizontally disposed heat exchange tubing. The delivery of air to the fluidized bed is regulated so as to establish a combustion zone of high turbulence and one or more heat transfer zones of lower turbulence. A plurality of heat exchange tubes are located in the heat transfer zone or zones and within the expanded bed level of the fluidized bed but above the region occupied by the slumped bed. Economizer heat exchange coils may be located in the passageway for exhaust gases.

Abstract: An integral generator/gasifier system in which a vapor generator is provided that includes an upright furnace section and a plurality of nozzles, each having one end registering with the interior of the furnace section. A gasifier extends adjacent to the furnace section and supports a bed of adsorbent material for the sulfur generated as a result of the gasification of fuel introduced to the gasifier. Air is passed through the bed of adsorbent material to fluidize said material so that, upon gasification of the fuel, a substantially sulfur-free product gas is produced. The other ends of the nozzles communicate with the gasifier so that the product gas passes from the gasifier through the nozzles and into the furnace section for combustion.

Abstract: A fluidized bed for the combustion of coal, with limestone, is replenished with crushed coal from a system discharging the coal laterally from a station below the surface level of the bed. A compartment, or feed box, is mounted at one side of the bed and its interior separated from the bed by a weir plate beneath which the coal flows laterally into the bed while bed material is received into the compartment above the plate to maintain a predetermined minimum level of material in the compartment.

Abstract: In a fluidized boiler system, the rate of fuel flow and bed depth are simultaneously controlled in response to variations in a load demand signal representing the need for steam output from the system. When the load demand changes, the rate of fuel flow is varied accordingly to provide a change in the bed temperature to thus provide a rapid response to the change in the demand signal. At the same time, the system changes the rate of flow of limestone to the bed and the rate of removal of spent particulate material of the bed to change the bed depth to respond more slowly to the change in the demand signal. As the depth of the fluidized bed approaches a value corresponding to the demand signal, the temperature of the bed will change back toward a median value.

Abstract: In a fluidized bed reactor having a reactor vessel, two detector vessels are mounted in the reactor vessel near the inside surface of the reactor vessel in the fluidized bed and in the gas outlet region. Each detector vessel contains larger detecting particles and passes the gas in the reactor vessel. Pressure drop across the detecting particles is measured. The ratio of the two pressure drops represents the ratio of the fluid velocity and minimum fluidizing velocity under the operating conditions and can be used as control factor.

Abstract: A fluidized bed heat exchanger in which a perforated plate is disposed within a housing for supporting a bed of particulate material. Air is passed through the plate to fluidize the particulate material and nozzles are provided for distributing air across the inlet end of a drain pipe for the spent particulate material to insure a continuous draining of the material.

Abstract: A system for supporting a fluidized bed in a boiler in which a plurality of support frames are supported in an abutting relationship spanning the interior of the boiler. One or more of the support frames are connected or attached relative to each other and to their supports in a manner to permit limited relative movement between the frames and between each frame and its support. A grid is supported by each frame and is connected or attached thereto in a maner to permit limited movement of the grid relative to the frame.

Abstract: A fluidized bed reactor which is capable of burning material containing incombustible matter which during operation accumulates in the form of large particles in the lower part of the reactor, is provided. A discharge system which causes coarse particles to be discharged in a continuous manner without discharging fine particles or combustible matter is provided. The discharge means comprises a discharge compartment connected to an outlet of the distributor plate of the reactor. An upward flow pipe is centrally disposed in the discharge compartment. Air is supplied to the lower part of the discharge compartment. Coarse particles are withdrawn from the discharge compartment through a discharge pipe. Fine particles are blown back to the reactor through the upward flow pipe.

Abstract: The invention relates to the method and equipment for treatment of fuel for fluidized bed combustion, which includes drying, classification and crushing of the fuel. The method for treatment of fuel comprises mixing the fuel with hot ash removed from the fluidized bed combustor and drying said mixture in a fluidized bed dryer in which the velocity of the fluidization fluid equals or is lower than the minimum fluidization velocity of particles in the fluidized bed combustor. The equipment for treatment of fuel comprises a bunker, crusher and dryer, comprising a fluidized bed dryer provided with appropriate piping for interconnection of the fluidized bed dryer, fluidized bed combuster, fuel bunker and crusher.

Abstract: A first atmospheric bubbling fluidized bed furnace is combined with a second turbulent, circulating fluidized bed furnace to produce heat efficiently from crushed solid fuel. The bed of the second furnace receives the smaller sizes of crushed solid fuel, unreacted limestone from the first bed, and elutriated solids extracted from the flu gases of the first bed. The two-stage combustion of crushed solid fuel provides a system with an efficiency greater than available with use of a single furnace of a fluidized bed.

Abstract: A process and system are disclosed for drying coal in a fluidized bed wherein the heat necessary for drying is provided by partial combustion of the coal in the bed. Proper control of the reaction parameters, particularly reaction temperature, provides an acceptably high drying rate along with an acceptably low production of pollutants in the off-gases. A particular embodiment of the invention provides for cooling of the dried coal by mixing such dried coal with an additional stream or additional streams of undried coal.

Abstract: A fluidized bed firing unit, in which a fluidized bed of comparatively inert material is maintained in a container having cooled or insulated walls and a flow-bottom by means of air entering through flow nozzles in the bottom, the fuel being fed to the fluidized bed after the latter has been heated to the ignition temperature of the fuel. The air supplied through the air nozzles in the flow bottom for the purpose of producing the fluidized bed, is forced into at least one component of motion causing the fluidized bed to circulate in a horizontal plane while the fuel is fed in the lower part of the fluidized bed, preferably in the area of approximately 20% of the bed height. The motion component moving the fluidized bed in the circulating motion is preferably produced by off center feeding-in of additional air. It is expedient if at least the air nozzles in the area of the container walls are inclined with respect to vertical in the same direction.

Abstract: Liquid fuel is distributed in a fluidized bed of refractory particles through the gas constriction plate of a fluidized bed incinerator. The fuel is supplied from a distribution system of circulation pipes situated well below the constriction plate and passed to the fluidized bed through risers by means of a small amount of driving agent, preferably steam, of high pressure supplied from a separate distribution system independently of the primary combustion air and the fluidizing gas. The driving agent and the fuel are passed into the risers through nozzles at the lower end of the risers.

Abstract: A fluidized bed reactor is provided with heat exchange coils for controlling the temperature of the fluidized bed, with only vertically oriented sections of the coils exposed to the erosive conditions in the fluidized bed. The vapor-liquid circuit, of which the heat exchanger coils are a part, is arranged to operate on the principle of natural circulation. At least some of the tuyere elements discharge fluidizing gas at a level substantially above the constriction plate and the bed solids below the level of the tuyere gas discharge constitute a static layer during fluidization in which the lower angle bends of the heat exchange coils are embedded and so shielded from erosion by the fluidized solids of the bed proper. The static layer of bed solids also accommodates thermal expansion of the lower angle bend due to elevated temperatures and insulates the constriction plate from the high temperatures in the reactor.