Abstract: This invention is a combustion process having a series of stages in which the fuel is combusted stepwise using specific catalysts (desirably palladium-bearing catalysts in the first two zones and metal and oxygen-bearing catalysts in the hot catalytic zone) and catalytic structures and, optionally, a final homogeneous combustion zone. The choice of catalysts and the use of specific structures, including those employing integral heat exchange, results in a catalyst support which is stable due to its comparatively low temperature and yet the product combustion gas is at a temperature suitable for use in a gas turbine, furnace, boiler, or the like, but has low NO.sub.x content.

Abstract: A combustion apparatus comprises: a large-diameter sleeve-like element forming an incoming passage through which an air/fuel mixture gas flows in a predetermined direction; at least one small-diameter sleeve-like element disposed in the incoming passage, which small-diameter sleeve-like element forms an outgoing passage through which a combustion gas having been issued from the incoming passage flows in a direction counter to the above predetermined direction; an air/fuel mixing unit for issuing the air/fuel mixture gas under a predetermined pressure to a main incoming port located in an upstream side of the incoming passage; an auxiliary incoming unit for issuing a combustion gas produced by a pilot burner to the upstream side of the incoming passage prior to supplying the air/fuel mixture gas to the incoming passage; and a combustion-gas outlet port for discharging the combustion gas having passed through the outgoing passage, which combustion-gas outlet port communicates with an outlet opening of the outgo

Abstract: A combustion process, e.g. for a gas turbine, comprises catalytically combusting part of a fuel/air feed in a preliminary catalyst body which has through passages and supports, or is composed of, a catalyst active for the combustion of the fuel. The resultant heated gas stream is then mixed with the remainder of the feed, and that mixture is combusted, e.g. catalytically in a main catalyst body. The amount of combustion occurring in the preliminary catalyst body is sufficient that combustion of the mixture of the heated gas stream and the remainder of the feed can be sustained at the desired operating conditions. Under those desired operating conditions combustion of the feed could not be sustained in the absence of the heating given by the combustion in the preliminary catalyst body. There may be more than one preliminary catalyst body.

Abstract: A low NOx burner assembly of a fuel-fired heating appliance is supplied with an air/fuel mixture having a substantially less than stoichiometric air-to-fuel ratio. The air-rich mixture is partially combusted to create primary combustion products disposed within an open inlet portion of a combustor structure having a catalytic converter operatively positioned within an open outlet portion thereof spaced apart from its open inlet portion. A flow of aspirating air is introduced into the combustor structure between the inlet and outlet portions thereof. The aspirating air mixes with the primary combustion products, cools them, and flows with them outwardly through the catalytic converter. This essentially completes the combustion of the remaining fuel within the cooled primary combustion products, and does so at a temperature not appreciably greater than the initial combustion flame temperature to thereby substantially reduce NOx emissions without the use of flame quenching techniques.

Abstract: A regenerative thermal oxidizer for removing pollutants from industrial exhaust gas flows by high temperature oxidation is composed of at least two regenerative units having a modular construction and a much more compact design than previously achieved in units of comparable size. The more compact design is achieved without any sacrifice in thermal efficiency by providing a regenerative bed having one hot-face area and two cold-face areas connected by an inlet/outlet crossover duct. The bed has "w"-shaped cross-section to support and contain interlocking heat-exchange elements without the use of hot-face or cold-face area retaining members. Each unit has inlet and outlet flow dividing mechanisms, an inlet duct, and an outlet duct. The inlet duct contains the inlet flow dividing mechanism and communicates with an inlet manifold and the cold-face areas for conducting process gas to the cold-face areas during inlet mode.

Abstract: The process obtains a plurality of small flames which become violet when combusting natural gas. In particular the amount of primary air induced is at least 80% of the air stoichiometrically required for combustion; the secondary air laps all sides of each singly small flame arising from the small group of slots on the burner body, in the area where each flame leaves the surface of the burner body so as to swell it making its width at least as big as its height and/or alternatively the contact surface between each flame and the secondary air is increased right from the first steps in combustion, so that each small group creates a small flame with two divergent bladed wings, similar to "butterfly wings.

Abstract: A gas combustion method and apparatus for performing such comprises supplying a fuel gas, generating a gas mixture composed of the fuel gas and external air, diffusing the gas mixture through a diffusion member to lower a flow velocity of thereof, putting the gas mixture to flaming combustion in a cylindrical combustion chamber thereby elevating the temperature of a combustion catalyst disposed to the downstream end of the combustion chamber by the heat of the flaming combustion, then ceasing the diffusion of the gas mixture to increase the flow velocity thereof in the combustion chamber, thereby extinguishing the combustion flame and directly supplying the gas mixture to the combustion catalyst. The gas mixture is put into and out of diffusion by an actuating mechanism that brings a diffusion member into and away from the entrance of the combustion chamber.

Abstract: Remarkable suppression of the formation of pollutants: NO.sub.x, CO and UHC, in the flameless combustion of gaseous fuel with excess air is achieved by passing the fuel and air through a porous surface combustor directly into an adiabatic zone, and by controlling the amount of excess air to be greater than about 50% but not greater than about 150% in excess of the stoichiometric requirement. The furnace with the adiabatic zone for the suppression of pollutants will preferably have a refractory body as part of the adiabatic zone.

Abstract: A nested fiber gas burner is formed with a burner body having an inlet on one end and a burner port on the other end. A mat of fibers is formed from discrete fibers of material randomly deposited into a mold having the general configuration of the burner port. After the fibers are deposited in the mold to a depth of about 0.5 inch, they are heated to a temperature of about 1200.degree. C. for about two hours, which causes the fibers to bond together. Thus bonded, the fiber mat is secured in place in the burner port.

Abstract: An process and apparatus are disclosed for fluidized bed catalyst regeneration in a cross-flow type regenerator. A baffled coked catalyst inlet located within the dense bed of catalyst disperses and distributes coked catalyst flow in a direction generally normal to the direction of flow in the catalyst inlet. The baffle significantly reduces the stagnant regions in the bed.

Abstract: This invention includes a multiple-stage combustion apparatus which can be used in a high-temperature environment, such as with a gas turbine. In particular, the invention includes a novel structure for the first stage of such apparatus, and a method of making that first stage. The first stage, which is an ignition stage, is a reactor formed of a metal strip which is coated with a catalyst on only one side. The strip is also corrugated with a herringbone pattern. The strip is then folded back and forth upon itself to form a reactor of a desired cross-section. The reactor has rows of channels that are formed between the layers of the metal. The single coated side of the metal defines the walls of the channels in every other row. The fuel-air mixture that flows through the coated channels is combusted. The fuel-air mixture that flows through the uncoated channels is not combusted, and cools the catalyzed surfaces.

Abstract: A staged combustor including a first combustion stage for combusting a fuel rich mixture of a fuel and an oxidizer. A plurality of serially positioned secondary combustion stages, downstream the first stage, are provided for receiving secondary flows of oxidizer to the increasing mass of combustion efflux. The gradual increase of oxidizer/fuel ratios provide a resultant substantially stoichiometric combustion. A cooling system is provided for cooling these combustion stages.

Abstract: An emission control fluidized bed reactor is disclosed. The reactor includes a central chamber with a fluidized bed at the base of the central chamber and circulating particulate matter above the fluidized bed forming a freeboard. The fluidized bed is maintained at a temperature range between 1500.degree. F. and 1600.degree. F. The freeboard is operated in a predetermined environment between 1600.degree. F. and 1700.degree. F. and with a velocity between 4 to 12 feet per second. An externally fed gas from a discrete industrial process such as an external combustion system or a plant process is conveyed into the freeboard. The externally fed gas includes pollutants which are suppressed as a result of the predetermined environment in the freeboard.

Abstract: A fluidized bed heat exchanger and a method of controlling same in which a first chamber and plurality of additional chambers are formed in a housing. A particulate material is supported in all of the additional chambers and air is introduced to each of the additional chambers to fluidize the material. Particulate material is introduced into one of the chambers and the chambers communicate to permit the material to flow between the chambers. Heat is extracted from one or more of the other additional chambers and the material upon exceeding a predetermined height flows from the other additional chambers to the first chamber before discharging via the first chamber externally of the housing.

Abstract: The grid plate is disposed between the fluidized bed reactor chamber and an underlying wind box and includes a plurality of nozzles for feeding fluidizing gas from the wind box into the reaction chamber. The nozzles are configured to afford different pressure drops across the grid such that with increasing pressure, additional nozzles are actuated in response to increasing pressure differences across the plate whereby fluidized bed start-up and steady state operating conditions may be facilitated.

Abstract: This invention is a comparatively high pressure combustion process having a two stages in which a fuel is stepwise combusted using specific catalysts and catalytic structures and, optionally, having a final homogeneous combustion zone. The choice of catalysts and the use of specific structures, including those employing integral heat exchange, results in an overall catalyst structure which is stable due to its comparatively low temperature. The product combustion gas is at a temperature suitable for use in a gas turbine, furnace, boiler, or the like, but has low NO.sub.x content.

Abstract: An arrangement for the avoidance of a deposition of a fatty substance, such as liquid lubricant or grease possessing high viscosity which is carried along with steam during a combustion of hydrogen from a gas mixture containing hydrogen, oxygen and steam, through the intermediary of catalytic igniters.

Abstract: A fluidized bed combustion furnace comprising a throttle section (12) formed directly above a fluidized bed (18) so that the flow velocity of combustion gas in the throttle section becomes higher than the terminal velocity of grains or particles of a fluidizing medium which have a mean diameter, secondary air supply ports (22) provided in the throttle section in a plurality of stages, a free board section (13) formed above the throttle section, the free board section having such a cross-sectional area that the gas flow velocity becomes lower than the terminal velocity of mean diameter grains or particles of the fluidizing medium, two or more combustion gas inlets (16a) and (17a) of combustion gas passages (16) and (17) provided in an area of the ceiling portion of the free board section which is not coincident with the plane of projection of the throttle section, and a junction chamber (25) provided at the outlets of the combustion gas passages so that high-temperature gases passing through the combustion gas

Abstract: A novel praseodymium-palladium oxide compound has the formula Pr.sub.4 PdO.sub.7. The compound has utility as a catalyst for oxidation of combustion mixtures comprising oxygen (e.g., air) and gaseous carbonaceous fuels such as methane and displays excellent regeneration characteristics after exposure to decomposition-causing temperatures. The compound may be used in a catalyst composition by being coated as a washcoat on a suitable carrier. Catalytic combustion processes are carried out by contacting such combustion mixture with the catalyst under combustion conditions, including catalytically supported thermal combusiton. Regeneration of over-temperatured catalyst is also provided for.

Abstract: A circulating fluid bed reactor comprises a reactor chamber having a circumscribing wall, a particle separator to receive a particle - gas suspension from the reactor chamber, and means for returning the particles separated by the particle separator to the reactor chamber. In order to eliminate problems due to heat expansion of the parts of the reactor and to provide a simple structure, the particle separator has at least one cyclone having a chamber with a cylindrical outer surface forming a part of the circumscribing wall of the reactor chamber.

Abstract: Method and apparatus are provided for establishing and controlling the stability and movement of a reaction wave of reacting gases in a matrix of solid heat-resistant matter. At least a portion of the bed is initially preheated above the autoignition temperature of the mixture whereby the mixture reacts upon being introduced into the matrix thereby initiating a self-sustaining reaction wave, after which, the pre-heating can be terminated. The stability and movement of the wave within the matrix is maintained by monitoring the temperatures along the flowpath of the gases through the bed and adjusting the flow of the gases and/or vapors or air to maintain and stabilize the wave in the bed. The method and apparatus provide for the reaction or combustion of gases to minimize NO.sub.x and undesired products of incomplete combustion.

Abstract: Apparatus for controlled low NO.sub.x combustion. First and second combustion zones are provided, each filled with a porous high temperature resistant matrix, the void spaces of which provide sites at which substantially all of the combustion occurs. The second zone is downstream of the first zone. Means are provided for mixing fuel and a gaseous source of oxygen and providing the resultant combustible mixture to the input end of the first combustion zone to establish fuel-lean conditions therein; and means for feeding the combustion products from the first zone to the second zone and augmenting same with further oxygen and sufficient additional fuel to create fuel-rich burning conditions therein to complete the oxidation of the products from the first zone.

Abstract: A radiant gas burner having a porous matrix bed with a cross-sectional area that diverges along a generally longitudinal axis in a direction from an upstream end to a downstream end of the porous matrix bed. The burner has a fuel/air inlet and a flow distributor positioned near a downstream end of the fuel/air inlet, for distributing the fuel/air mixture throughout the porous matrix bed. A radiant surface layer is positioned adjacent and downstream from the downstream end of the porous matrix bed. The fuel/air mixture is combusted within the porous matrix bed and a combustion flame is stabilized completely within the porous matrix bed. The porous matrix bed is constructed as a bed of refractory particles.

Abstract: An arrangement is provided for locating internal cooling coils in an FCC regeneration zone that allows control of the cooling coil wall temperature independently of the regeneration zone operation and the circulation rate of cooling fluid through the cooling conduits. The cooling conduits are located within a vessel that contains the combustion section for an FCC regeneration zone. The cooling coils are in a chamber that is closed to catalyst transfer across all of its boundaries except its top. The level of hot regenerated catalyst within the regeneration zone is maintained above the top of the cooling chamber. The addition of flue gas to a lower portion of the cooling chamber provides a random exchange of catalyst particles between the layer of the catalyst bed above the chamber and catalyst within the chamber. By controlling the rate of fluidizing gas addition to the chamber, the rate of exchange of hot catalyst between the chamber and the bed is also controlled.

Abstract: Burner apparatus for use in controlled low NO.sub.x combustion. Mixing and flow-directing means receive and mix fuel and air provided thereto and form a flow of the resulting combustible mixture. A combustion zone defined by a porous high temperature-resistant matrix includes an input end for receiving the combustible flow. Cooling means are mounted in proximity to the input end of the combustion zone, for maintaining the temperature of the flowing combustible mixture proximate the input end below ignition temperature, thereby limiting the flame produced by combustion in the porous matrix to the downstream side of the cooling means. The method for controlled low NO.sub.x combustion is also disclosed and claimed.

Abstract: A fluidized bed combustion system and method in which a recycle heat exchanger is located adjacent the furnace section of the combustion system. A mixture of flue gases and entrained particulate materials from a fluidized bed in the furnace section are separated and the flue gases are passed to a heat recovery section and the separated particulate material to the fluidized bed in the recycle heat exchanger. A first chamber and plurality of additional chambers are formed in the recycle heat exchanger. A particulate material is supported in all of the additional chambers and air is introduced to each of the additional chambers to fluidize the material. The separated particulate material from the fluidized bed in the furnace section is introduced into one of the chambers and the chambers communicate to permit the material to flow between the chambers.

Abstract: A fluidized bed combustion system and method in which a recycle heat exchanger is located adjacent the furnace section of the recycle heat exchanger. Heat exchange surfaces are provided in one compartment of the heat exchanger for removing heat from the solids, and a bypass compartment is provided through which the solids directly pass to the furnace during start-up and low load conditions. A separate cooling compartment for the separated solids is disposed in the recycle heat exchange and valves are provided to selectively control the flow of solids between compartments.

Abstract: In a radiant burner whose head has a ceramic incandescent body with individual burner channels, the interior of the incandescent body (3) is provided with a metallic coating (7) which extends into each of the burner channels (6) and which is closed except at the entries to the channels.

Abstract: A device for use in heating or incineration plants for use as a waste gas filter to eliminate and/or convert harmful elements in the waste gas is disclosed. The device of the subject invention can eliminate soot and soot-like products, or it can serve as a heat exchanger or as a mixing component for a furnace. The device of the subject invention comprises a sintered body made of one or more compression molded highly heat resistant sintered parts. The sintered body manifests high porosity and/or a multitude of intake and outlet channels.

Abstract: Fluidized bed reactor method and apparatus for removal of coarse material from the reactor. The apparatus comprises a discharge device including a substantially vertical pipe portion connected at one end with an outlet opening in the reactor grid, and at another end to an aeration chamber containing a discharge opening located below the level of the grid outlet opening; and a device for supplying pressurized air in short blasts of 30 to 100 milliseconds, preferably at pressures of from 2.5 to 7.0 bar, into the aeration chamber in the direction of the discharge opening to remove the coarse material from the reactor. Low pressure fluidizing air may be supplied to the vertical pipe portion as well as the aeration chamber to return small particles in the discharge device to the fluidization zone of the reactor.

Abstract: The present invention relates to a fluidized bed apparatus comprising a fluidization grid arranged in the lower part of this apparatus, this grid being provided at its center with a circular aperture communicating with a discharge chamber and occurring in the form of a surface of revolution consisting of the joined lateral surfaces of at least two coaxial truncated cones of revolution, virtual vertices of which are oriented downwards.

Abstract: Low NO.sub.x combustion is effected by a method wherein a fuel, e.g., natural gas, and a source of oxygen, e.g., air, are mixed and the mixture is combusted in at least two successive combustion zones filled with a porous matrix, the void spaces of which provide sites at which substantially all of the said combustion occurs; viz. a first zone wherein the mixture is fuel-rich, and a second zone wherein the mixture is fuel-lean. Preferably, the method utilizes an additional combustion zone which precedes or is upstream of the first zone and is filled with a said porous matrix, wherein the mixture is fuel-lean. Apparatus for low NO.sub.

Abstract: A high efficiency linear gas burner assembly having a mixture manifold assembly for delivering a combustible gas and air mixture to a burner. The mixture manifold assembly supports an elongate, channel-shaped, secondary air plenum which receives therein a burner housing. The burner housing supports two, spaced, parallel plates, each having apertures therethrough. The gas/air mixture is delivered through the mixture manifold assembly and secondary air plenum to the burner housing where the mixture passes first through the apertures of the lower plate, then between the plates, then through the apertures of the upper plate or burner surface. The size and number of apertures in the upper plate and the space between the plates ensures that the flame remains stable during a wide range of turndown, and that the flame does not retrogress through the burner apertures. Secondary air ports are provided along the interior of the secondary air plenum to provide additional air for combustion.

Abstract: A circulating fluid bed combustion (CFBC) unit, which burns a carbon and nitrogen containing fuel to produce heat and flue gas comprising NO.sub.x, operates with reduced emissions of NO.sub.x from the flue gas by adding to the circulating fluid bed a catalytically effective amount of a DeNO.sub.x catalyst, such as bismuth oxide on a silica/alumina support. The DeNO.sub.x catalyst may circulate freely with the circulating inventory of particulates in the CFB, or can be disposed on a heavier particle which "slips" and has an extended residence time in the combustion zone where the carbonaceous fuel is burned. A CO combustion promoter, such as Pt on silica/alumina may also be present.

Abstract: Nitrous oxide emissions are reduced in an industrial thermal process and system which operates a gas fired burner at substantially sub-stoichiometric conditions to produce products of combustion rich in combustibles and control flame temperatures at temperatures which do not exceed predetermined levels. Completion air at stoichiometric proportions is subsequently employed to burn the combustibles. Regenerative and recuperative means to cool gases after each partial combustion step are used to extract heat and use is in conventional heating processes. A novel regenerative heat exchange system is used to extract heat from the gases so that the gases never exceed a temperature whereat nitrous oxide formation tends to occur.

Abstract: The present invention relates to a method and a regenerator for heating gases, by alternatingly first heating heat carriers, preferably a bed of heat carrier bodies, and thereafter utilizing this energy stored by the heat carriers to heat cold gases. The essential feature of the invention is that a loose bed of the heat carriers is located between two coaxial and equidistant grates of the regenerator, and that the hot gas flows through this bed from the inside to the outside during the heating up phase of the regenerator and the cold gas flows through it in the reverse direction, from the outside to the inside, during the gas heating phase. This method and the regenerator provide advantages for gas heating due to lower thermal losses of the regenerator itself, and increased heat transmission is obtained due to large heat exchange surfaces of the heat carriers in a bed with a relatively low pressure loss for the gas flowing through.

Abstract: A regenerative burner includes a chamber containing heat storage bodies which extract heat from hot products of combustion flowing through the burner during one part of a cycle of operation and yield up that heat to incoming air during a further part of the cycle.

Abstract: A fluid bed processing apparatus in which a series of individual fluid bed modules are arranged horizontally alongside each other in a linear or circular configuration with the bed material overflowing weirs between each module in moving from the feed stock input module to a discharge module.

Abstract: The invention relates to a method and a nozzle bottom for controlling the mixing of gaseous flows in fluidized bed reactors and circulating fluidized bed reactors. In the method, part of the combustion air is introduced into a reactor chamber through fluidizing nozzles (11) positioned in a nozzle bottom (4). In order to improve the controllability of a combustion process, the remaining part of the combustion air is according to the invention introduced through essentially vertically directed jet nozzles (12) positioned in the nozzles bottom (4), and the vertical penetration of the air jets applied through the jet nozzles (12) is maintained at a value essentially higher than the vertical penetration of the air jets applied through the fluidizing nozzles (11).

Abstract: A regenerative bed incinerator 10 incorporates a dwell chamber 18 disposed between a pair of spaced regenerative heat exchange the beds 14A and 14B, one of which serves as a gas preheating bed and the other of which serves as a gas cooling bed. At periodic intervals, the direction of flow through the incinerator 10 is reversed so that the functions of the beds 14A and 14B is reversed. A hot gas vent duct 80 is provided for selectively bypassing a portion 7 of the hot, incinerated process exhaust gases 5 around the gas cooling bed into the gas exhaust duct 70 for venting to the atmosphere. A bypass damper 88, which is controlled by control means 86 in responsive to exit gas temperature measurements from thermocouple 90, is positioned in the hot gas vent duct 80 to control the amount of hot, incinerated process exhaust gases bypass around the gas cooling bed.

Abstract: The grid plate is disposed between the fluidized bed reactor chamber and an underlying wind box and includes a plurality of nozzles for feeding fluidizing gas from the wind box into the reaction chamber. The nozzles are configured to afford different pressure drops across the grid such that with increasing pressure, additional nozzles are actuated in response to increasing pressure differences across the plate whereby fluidized bed start-up and steady state operating conditions may be facilitated.

Abstract: A gas trubine combustor includes a main body with a combustion portion into which mixture of fuel and air is supplied. The gas mixture is burned through a catalytic reaction at a catalyst body arranged in the main body. The gas mixture passed through the catalyst body is introduced into a gas phase combustion portion provided in the main body. Between the catalyst body and the gas phase combustion portion is arranged a dividing unit which has a plurality of branch passages. The gas mixture passed through the catalyst body is divided by the dividing unit into a plurality of gas streams flowing through the branch passages. Each of the gas streams is mixed with fuel supplied from a fuel supply tube.

Abstract: Process for heating a catalyst used for the catalytic high-temperature oxidation of a mixture of a combustible gas and air or oxygen which is introduced in the cold state. The mixture is ignited on the input side at a point which is so close to the catalyst that the mixture is burning when it reaches the surface of the catalyst.

Abstract: A system and method for controlling the sealing efficiency and recycle rate in a fluidized bed reactor in which air is introduced into two chambers found in a sealing vessel for receiving the separated solids from the separator. The air is introduced into two chambers in the sealing vessel in a direction opposite to that of the flow of the separated solids through the vessel. One of the chambers is located below the separator dipleg and in alignment therewith and the other chamber surrounds the first chambers. The air flow through each path can be separately adjusted as necessary.

Abstract: A method and apparatus for modulating the surface area of a radiant infrared burner over which combustion occurs as a function of burner heat output rate. This modulation serves to maintain the heat flux density on the surface of the burner at or near an optimum value over a range of heat output rates. The modulation is effected by means of a piston disposed in the internal cavity of a burner which blocks the passage of combustible gas to areas of the burner downstream of the piston from the gas inlet to the burner. The piston is displaced further downstream with increased gas flow rate resulting in combustion occuring over an increased area of the burner surface as burner heat output rate is increased. In its simplest embodiment, the invention comprises a burner oriented vertically with the combustible gas entering the bottom of the burner and a free piston which floats on the incoming gas stream at a level within the burner which is proportional to the gas flow rate.

Abstract: Process and apparatus for catalytic combustion in which a combustible gas stream is mixed with part of the recycled hot product stream and then fed to a combustion zone containing a combustion catalyst, and from which the hot pressurized product is obtained. The recycle is preferably effected by means of a constriction at the end of the inlet gas supply producing a region of lower pressure than the pressure of the product gas.

Abstract: A circulating fluidized bed reactor comprises a separator including a vortex chamber adjacent the top of the reactor for separating solid material from the flue gases of the reactor. A channel directs flue gases discharged from the reactor and adjacent the top of the reactor in a downward direction. A main portion of the solid material is separated from the gases by a change of flow direction after which the solid material is returned to the lower part of the reactor. The main portion of the gases is directed, after the change of direction, to the vortex chamber where further separation of solid material is effected and the separated solid material is returned to the reactor.

Abstract: Solid material which is carried out of a fluidized bed reactor with the gas discharged therefrom and which is separated off in a separator is returned to the reactor by way of a recycling means. To reduce problems caused by virtue of differing pressure levels within the system in the recycling operation, the pressure in the recycling means between the separator and the upper boundary of a bed of solid material which is formed in the recycling means is reduced by suction removal of gas to a pressure level which is no higher than or even lower than the lowest pressure in the separator which in turn is lower than the pressure in the reactor.

Abstract: Disclosed is a catalytic combustor and systems for the boilerless stoichiometric production of a working fluid such as steam from a fuel-mixture comprised of a carbonaceous fuel and a diluent such as water mixed in a thermally self-extinguishing mass ratio. Production of the steam is by a controlled substantially stoichiometric process utilizing a combustor to provide steam over a wide range of heat release rates, temperatures and pressures for steam flooding an oil bearing formation. Even though formation characteristics change during a steam flooding operation, output steam of the combustor may be kept at a constant heat release rate by dividing the total amount of water passing through combustor between a first portion which is included in the fuel-mixture and a second portion which is injected into the heated products of combustion.

Abstract: Disclosed herein is a fluidized-bed reaction apparatus comprising a perforated plate located in the lower portion of a fluidized-bed reaction tower for forming fluidized-bed of particles thereon, the plate having regions with different opening ratios, at least the outer peripheral portion and the geometrical center portion of the plate having an opening ratio larger than an average opening ratio of the plate, inlets of a heating-fluidizing gas and the particles receiving the reaction, outlets of the particles and a discharge gas, and a fluidized-bed reaction process using such an apparatus. Upon operation of the apparatus, stationary circulation of the particles is obtained in the fluidized-bed thereby the particles are scarcely pulverized or entrained and the circulation velocity is increased.