Abstract: The invention relates to a process for regenerating used foundry sand, whose original molding sand contained, as the molding material, inorganic binders such as, for example and especially, bentonite ("inorganic used sand") and/or organic binders such as, for example and especially, phenolic resins and/or furan resins ("organic used sand"), wherein the used sand to be reconditioned is impregnated with water and then transferred in the moist state into a heated fluidized bed.

Abstract: An aeration rod-out assembly for aerating a flow of solids in a pipe is disclosed comprising an aeration pipe with first and second ends, the first end connected to the pipe containing the flow of solids and a cap connected to the second end. A rod is slidably disposed within the aeration pipe and said cap for axial movement therein between first, second and third positions such that as the rod is moved from its first position to its third position the rod ejects from the aeration pipe solids which settle into the housing. A shaft connected to the rod projects from the cap for actuation of the rod. First and second hoses register with the aeration pipe and the cap respectively to deliver aeration gas to the assembly, which gas discharges through the first end of the aeration pipe to aerate the flow of solids when the rod is in its first position but is substantially blocked from discharging when the rod is in or between its second and third positions.

Abstract: A fluidized bed reactor in which partitions disposed within a vessel form first and second furnace sections, first and second troughs and a heat exchange section such that the first trough is disposed between the first furnace section and the heat recovery section and the second trough is disposed between the second furnace section and the heat recovery section. A fluidized bed is formed in each of the furnace sections for the combustion of fuel to generate heat and to generate a mixture of combustion gases and entrained particulate solids. The mixtures from the furnace sections are received in first and second horizontal cyclone separators, both formed within the vessel for separating the entrained particulate solids from the combustion gases. Outlet means extend from the horizontal cyclones to discharge the separated solids to the first and second troughs respectively.

Abstract: A system for material drying comprising a pulse combustor and an associated combustion chamber whereby a pulsating flow of hot gases are generated. A tail pipe is connected to the outlet of the combustion chamber for receiving the pulsating flow of hot gases and a material introduction chamber is connected at the outlet of the tail pipe. A drying chamber is connected at the outlet of the material introduction chamber. The hot pulse combustion exhaust gases are cooled to control the temperature of the gases issuing from the outlet of the tail pipe and entering the material introduction chamber. This control is accomplished with a cool air stream issuing into the pulse combustion mixing chamber along with the hot gases from the pulse combustion tail pipe for mixing with and cooling of the hot gases. A separate diluent air stream may be employed for contact with material issuing from the introduction chamber and passing into the drying chamber.

Abstract: A method and composition for improving hole mobility in electrophotographic photoreceptors and other devices that comprises using certain polymers as binders.

Abstract: An apparatus for roasting coffee beans or the like includes a controlled spinning bed or fluid bed roaster in combination with a cyclone separator for removing chaff from the heating medium. The cyclone separator is disposed above and in coaxial and abutting relationship with the roaster. The separator has a generally cylindrical shape with a plate having a plurality of louvers in the base thereof. The louvers impart rotational movement as the heating medium passes therethrough so that the chaff can be removed therefrom. In a preferred embodiment of the invention, a second centrifugal separator which is relatively small with respect to the first separator is disposed adjacent the first separator for making a final separation and returning the heated medium to the roaster.

Abstract: A weir gate assembly includes a substantially rectangular weir gate immersed in a fluidized bed of material with a pair of resilient links rotatably connecting the weir gate and the material conveying trough through which the flow travels. A rotatable arm is pivoted on the housing and is connected to the weir gate such that rotation of the arm varies the configuration of the weir gate within the fluidized bed of material. Rotation of the arm forces a lower weir edge into sealed engagement with the conveying trough and deforms the links such that the relationship of an upper weir edge to the lower weir edge is varied to regulate the depth of the flow. A guide slot with a clamp bolt is provided for guiding rotation of the rotatable arm and maintaining the configuration of the weir gate.

Abstract: A fluidized bed reactor in which partitions disposed within a vessel form first and second furnace sections, first and second troughs and a heat exchange section such that the first trough is disposed between the first furnace section and the heat recovery section and the second trough is disposed between the second furnace section and the heat recovery section. A fluidized bed is formed in each of the furnace sections for the combustion of fuel to generate heat and to generate a mixture of combustion gases and entrained particulate solids. The mixtures from the furnace sections are received in first and second horizontal cyclone separators, both formed within the vessel for separating the entrained particulate solids from the combustion gases. Outlet means extend from the horizontal cyclones to discharge the separated solids to the first and second troughs respectively.

Abstract: A process and apparatus to treat powdered minerals placed in gaseous suspension by thermal exchange. The process includes the steps of preheating the minerals to be treated by the exhaust gas from a furnace. The minerals are then treated in the furnace. The minerals are then cooled with a stream of air prior to introducing the stream of air into the furnace. The furnace exhaust gases are filtered before being released into the atmosphere. A majority of the filtrate is mixed with the minerals leaving the furnace. The remainder of the filtrate is placed in suspension in a current of air diverted from the current of warm air which cools the minerals leaving the furnace. The remainder of the filtrate is separated from the air. The remainder of the filtrate is then mixed with the treated minerals and at least partially cooled. The diverted air is mixed with the furnace exhaust gases.

Abstract: The present invention relates to an apparatus treating waste comprising introducing a glass or mineral fiber substrate (7) contaminated with organic materials into a chamber (1) of a furnace by means of a conveyor belt (4), subjecting it to a gas consisting of a neutral gas and between 0 and 10% by volume of oxygen, heated to a temperature below the melting temperature of the waste substrate in order to pyrolyze the organic materials, and recovering the waste substrate. This apparatus has particular application to the recovery of the vitreous material forming the waste substrate, in order to recycle it for use in a glass melting furnace.

Abstract: An apparatus for preheating a granular material having a suspension preheater including a plurality of stages of cyclones arranged above a calcination furnace such that the granular material is preheated by waste gas from the calcination furnace as the granular material passes through the suspension preheater. The apparatus has a precalciner of fluidized-bed type or spouted-bed type connected, in place of a duct used in conventional apparatus, between a collecting cyclone directly connected to be calcination furnace and a first cyclone constituting the most downstream stage.

Abstract: An improved fluid bed furnace is disclosed which is useful in heat treating products or particles which are to undergo a change due to exposure to high temperatures. The bed is heated by lamps effectively buried in the bed radiating energy to the fluidized particles. In one embodiment, the lamps are protected by a ceramic tube with the lamps heating the tubes which in turn heat the fluid bed.

Abstract: A pulse combustor apparatus for burning solid fuel comprises a Rijke-type combustor tube and has a rotating fuel bed for defining a primary combustion zone adjacent the fuel bed. The rotating fuel bed tends to minimize agglomeration of solid fuel and accumulation of ash during combustion by agitating the solid fuel. An inlet conduit is provided for introducing a low nitrogen gaseous fuel to the combustion air upstream of the combustion zone to minimize the formation of NO.sub.x in the primary combustion zone. In other embodiments, inlets are provided downstream of the primary combustion zone for introducing additional air or gaseous, low nitrogen fuel for air staging or reburning to minimize the emission of NO.sub.x. Sorbents, such as limestone, are introduced above the bed to minimize SO.sub.2 emissions.

Abstract: By a method for heat treatment of pulverous material, e.g. burning of lime, the lime is first preheated by means of exit gas in a preheater (1, 2, 3) and subsequently burnt in a calciner (4, 14), after which the burnt lime is cooled in a cooler (6, 7).In order to be able to alter the reactivity of the finish-burnt lime, the calciner is divided into two chambers, namely a first chamber (4) in which the lime is burnt at, e.g. 1050.degree. C. and a second chamber (14) in which a larger or smaller portion of the lime is further burnt at a higher temperature, e.g. 1300.degree. C.By means of a splitting gate (16) in the outlet from a separation cyclone (5) for the calciner (4, 14), it is possible to determine the size of the portion of lime which should be exposed to the higher burning temperature in the second calciner chamber (14) and consequently to predetermine the reactivity of the finish-burnt lime.

Abstract: An apparatus and method for decontaminating contaminated microspheres of a patient support system employing a fluidizing medium to fluidize the microspheres to provide support for the patient, includes a tank for containing the microspheres. The tank includes a diffuser mounted inside the tank to form a plenum in the bottom of the tank. A rigid shell surrounds heat-insulating material around the outside of the tank. A recirculation channel is defined in the shell. A cover seals the tank. An air heater member and a gas blower provide hot air to fluidize the microspheres inside the tank. A valve permits a heating mode of operation, a cooling mode of operation, and a holding temperature mode of operation. The valve is switched between modes by action of a solenoid or a motor. A temperature probe monitors the temperature inside of the tank. A control circuit controls the air heater, the valve, and the gas blower according to a predetermined timed sequence of actuation.

Abstract: Dynamic fluidized-bed reactor for carrying out a chemical or physical multi-component process, which said reactor comprises a preferably vertical, cooled or uncooled reactor chamber and a preferably horizontal cyclone that discharges the solid matter through the side of the separator chamber and the gases through one end or both ends of the separator chamber. The reactor further comprises a discharge pipe with no gas lock, which allows the solid matter to fall freely. In different applications, the reactor may include feed and discharge means for solid matter as well as a gas distributor grate. Exemplifying embodiments are a fire-tube boiler and a reactor for purification and cooling of hot gases.

Abstract: A fluidized bed particulate material treating apparatus is provided having a fluidizing bedplate formed with apertures of a frusto-conical configuration. The apertures are formed with walls divergent from an exit end at an angle in the range of 25-45 degrees with a plurality of apertures formed in the bedplate in closely spaced relationship resulting in interaction of the airflow from the apertures to levitate the material as it is transported over the bed by the air flowing through the apertures.

Abstract: A process and apparatus for thermal agglomeration of high melting temperature ashes in fluidized bed processes is disclosed. Carbonaceous material to be combusted, incinerated or gasified is introduced into a fluidized bed supported on a perforated sloping supported grid through which a fluidizing gas is injected. An upflowing discharge control gas is injected through a density/size solids withdrawal conduit in communication with the base of the perforated sloping support grid. Positioned within the solids withdrawal conduit is a central jet pipe through which fuel and oxidant are injected into the base of the fluidized bed forming a hot temperature zone in which ash melts and agglomerates. Positioned above the perforated sloping support grid and peripherally mounted through the reactor wall are one or more burners through which fuel and oxidant are injected into the fluidized bed forming supplemental hot temperature zones in which ash melts and agglomerates.

Abstract: The present invention relates to a method of treating waste comprising introducing a glass or mineral fiber substrate (7) contaminated with organic materials into the chamber (1) of a furnace by means of a conveyor belt (4), subjecting it to a gas consisting of a neutral gas and between 0 and 10% by volume of oxygen, heated to a temperature below the melting temperature of the waste substrate in order to pyrolyze the organic materials, and recovering the waste substrate. This method has particular application to the recovery of the vitreous material forming the waste substrate, in order to recycle it for use in a glass melting furnace.

Abstract: A method for enhancing the efficiency of a thermal process such as calcination. The incoming solid particulate material is preheated in the conveyor by partially cooled exhaust vapors from the thermal processor. In passage through the conveyor, the cooled, intermediate temperature vapors contact, fluidize and heat the particulate solids to increase the available throughput of the system.

Abstract: A heat recovery system is disclosed for a pulse combustion drying system in which the exhaust gas of combustion from a pulse combustor passes successively through a dryer, a product collector and a scrubber. The heat of the exhaust gas is recovered in the scrubber by spraying with water or other liquid and transferring by heat exchange the heat absorbed by the water to compressed air, and passing the heated compressed air successively through a membrane heat exchange tube on the wall of the product collector and a membrane heat exchange tube on the wall of the dryer. The air is discharged finally in an air-injection nozzle of the pulse combustor.

Abstract: A method and apparatus for heat treating a particulate product including fluidizable as well as non-fluidizable particles. The particles are fed to a first perforated bed plate of a fluidized bed apparatus comprising at least one further stage formed by a second perforated bed plate. Heat treating gas is supplied upwardly to the first and second bed plates to fluidize the fluidizable particles thereon. The non-fluidizable particles are moved from the first bed plate into at least one discharge passage opening in the first bed plate. A flow of classifying gas is directed upwardly through the discharge passage to prevent fluidizable particles from leaving the fluidized bed through the discharge passage, while non-fluidizable particles are allowed to be discharged. The fluidizable particles are transferred from the first stage into the second stage for further treatment.

Abstract: A method of attaining a uniform flow in an elongated fluidized bed furnace, used for the purpose of preventing the expansion and uniting of bubbles in the fluidized bed, and setting the fluidized bed in a uniform flow state, so as to keep the flow condition of the bubbles excellent at all times. The purpose of this method can be achieved by withdrawing a fluidized gas from an arbitrary portion of a fluidized bed (13) through a fluidization gas venting or purging means (A).

Abstract: A fluid bed dryer granulator which can be unloaded by moving the support screen downwardly relative to the product chamber so that the product can be moved radially out of the device. Portions of the machine can be pivoted so as to allow rapid and thorough cleaning of the device.

Abstract: A fluidized bed system in which a plate is disposed in an enclosure and is adapted to support particulate material. A plurality of nozzles are supported by the plate for receiving air and directing the air through the plate and into the particulate material to fluidize same. Each of the nozzles comprises a vertical portion extending upwardly from the plate for receiving air from the plenum and a horizontal portion extending below the upper portion of the vertical portion for discharging the air.

Abstract: A continuously operable fluidized bed vessel system and method for incinerating and disposing of materials which produce high tramp residue. The system is particularly effective in combusting shredded tires and disposing of large amounts of wire tramp without requiring down-time for cleaning. Emission of undesirable gases is controlled by a sensing and controlling system which provides for automatic injection of combustion by-product-modifying gases and solids. Further control of undesirable gas emission is controlled by employing sealed combustible material input and solid waste output ports. Fluidizable bed material which is entrapped and discharged with the other residue is separated from magnetic tramp and larger grain sized non-magnetic tramp and recycled to continuously replenish the fluidized bed.

Abstract: It is an object of the present invention to provide a pulse combustion method and a valveless pulse combustor in which the strong sound wave energy and the combustion gas generated by explosions in the combustion chamber are effectively used for drying of a substance with no waste of sound wave energy and heat of the combustion gas.A pulse combustion method according to the present invention is characterized by a step of pushing the sound wave energy and the combustion gas which flow toward the air intake back to the combustion chamber by jetting a compressed gas toward the air intake. By means of this step, the sound wave energy and the combustion gas which were generated at the time of explosion in the combustion chamber and flow toward the air intake are pushed back to the combustion chamber and further to the exhaust pipe by a stream of the compressed gas. This enables the sound wave energy and the combustion gas which have been conventionally wasted to be used for drying of a substance.

Abstract: The present invention relates to a method for production of metals and/or ferro alloys by prereduction of particulate metal oxide co-current with a reducing gas. Reducing gas having a temperature between 650.degree. and 1100.degree. C. and metal oxide particles are supplied at the lower end of a substantially vertical prereduction column which comprises at least two chambers having a substantially circular cross-section, said chambers in their upper and lower ends having a decreasing cross-section and where a ringshaped member for decreasing the cross-section is arranged in the intermediate zone between the chambers. The mixture of reducing gas and prereduced metal oxide particles is collected at the top of the prereduction column, whereafter the prereduced metal oxide particles are transported to a smelting furnace for smelting and final reduction to metallix state by addition of a reduction material.The present invention also relates to a column for treatment of particulate solid materials with a gas.

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: Matter to be treated is passed through at least two treating regions sequentially wherein a bed of the matter is moved in a band continuously along an annular path by passing fluid through the bed along the path. The annular paths of the regions are concentric.

Abstract: A process and apparatus for the preparation of green briquettes for the production of silicon or silicon carbide or ferrosilicon in electric pit furnaces, quartz sand, a carbon carrier and a bituminous binder being mixed together, the mixture being shaped into blanks from which the green briquettes are formed by heat treatment. The process is performed with the use of blanks which are free from melted bituminous caking coal and whose specific weight is made greater than the bulk density of quartz sand by adjustment of the proportions of the mixture and by compacting. The blanks are introduced for the heat treatment into a heated rotating drum furnace whose lower part is filled with quartz sand to an extent such that the heat treatment proceeds in a dip bed of quartz sand.

Abstract: A fluidized bed combustion system and method in which a recycle heat exchange section is located within an enclosure housing the furnace section of the combustion system. The flue gases and entrained solids 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 heat exchange section. The heat exchange section includes a bypass chamber for permitting the separated solids to pass directly from the separator, via an outlet chamber, to the furnace section. A heat exchange chamber is provided in the recycle heat exchange section which receives the separated materials from the bypass chamber and transfers heat from the separated material to a fluid flow circuit for heating the fluid flow circuit and reducing the temperature of the separated material. The separated material in the heat exchange chamber is then passed back, via the outlet chamber, to the furnace section.

Abstract: Processes and apparatus for the thermal treating of articles, particulary for the quench hardening of metal alloys in an improved fluidized bed containing from 21 to 60 weight percent of fine alumina particles having a size from 20 to 100 microns and from 40 to 79 weight percent of coarse alumina particles having a size from 150 to 2000 microns.

Abstract: A continuously operable fluidized bed vessel system and method for incinerating and disposing of materials which produce high tramp residue. The system is particularly effective in combusting shredded tire and disposing of large amounts of wire tramp without requiring down-time for cleaning. Emission of undesirable gases is controlled by a sensing and controlling system which provides for automatic injection of combustion by-product-modifying gases and solids. Further control of undesirable gas emission is controlled by employing sealed combustible material input and solid waste output ports. Fluidizable bed material which is entrapped and discharged with the other residue is separated from magnetic tramp and larger grain sized non-magnetic tramp and recycled to continuously replenish the fluidized bed.

Abstract: A fluidized bed system comprises at least three cells constituting a fluidized bed. One of the cells interposed between other cells may function as a non-fluidized bed cell in response to the operating condition of the system.

Abstract: In a fluidized bed thermal reactor. It includes a main housing including a waste inlet, an exhaust gas outlet, an incombustible solids outlets, a base member, a fluidizable medium located on the base member, a plurality of gas inlets in the base member.

Abstract: A fluid bed dryer for processing a particulate material includes a series of chambers separated by longitudinally extending common walls and connected by turn-around sections to provide a serpentine path for the material. Each turn-around section is open to adjacent chambers at one end of one of the common walls to receive and turn particulate material distributed across the width of one of the chambers through an arcuate path and deliver the material to the other chamber. Each of the chambers and turn-around sections have a base including a number of gas introduction openings oriented to introduce gas in a specific direction to fluidize and move the particulate material in that direction. The gas introduction openings in the turn-around sections are oriented to successively receive and turn incremental vertical columns of the particulate material in accordance with the distance each incrmental vertical column is spaced from the common wall.

Abstract: An improved flame holder based tunable pulse combustor, and a processing system employing same. The processing system is for thermal, chemical, and physical processes which employ natural acoustic modes in a processing chamber to enhance the processing. An acoustically resonant processing chamber is provided as the processing vessel. A frequency tunable pulse combustor comprising a flame holder is positioned to excite natural acoustic modes in the processing chamber. Material introduced into the processing chamber is thereby subjected to acoustic pulsations while the material is being processed. The acoustic excitations in the system result in improved moisture removal and particle heating. Also disclosed are various embodiments of frequency and amplitude tunable pulse combustors which may be employed to excite the natural acoustic modes in the processing chamber, including axially translatable acoustic decoupler and flame holder configurations.

Abstract: Oven for dehydrating pulverulents, sand or granules, comprising an energy-saving dehydration device, adapted to gypsum burning. The device consists of an outer casing, an inner casing and flow cones disposed on said casings. A burner and a lock complete the device. Pressure within the oven is increased by the provision of a cover, a gypsum lock and a steam valve. The process takes place in dry or moist conditions, the latter being advantageous for the processing of insulating products or for gypsum amending the nature of plaster. Heat exchange enables the products to be processed at low temperatures. The central combustion chamber prevents loss by radiation. Application to gypsum burning, during which the device has demonstrated energy savings of 50% in comparison with traditional appliances.

Abstract: An apparatus to be applicable as a boiler for incinerating wet refuse in a combustion chamber with a fluid and heat medium of solid particles fluidized by an air feed to form a fluidized bed, with the aid of combustion of auxiliary fuel effected below the fluidized bed, is provided with additional one or more adjacent upper fluidized fed chambers in series to have the wet refuse dried and partially incinerated in the lower primary fluidized bed chamber with the balance of the refuse in a form of unburnt carbon particles being forced to fly upward into the additional upper fluidized bed chambers and be incinerated therein. Heat recovery is carried out from a topmost fluidized bed chamber.

Abstract: A pulse combustion energy system including a pulse combustor coupled to a processing tube for flowing material to be processed therethrough, the processing tube being coupled to a pair of cyclone collectors for receiving the material flowing therefrom. An optional recycling section is coupled to the cyclone collectors for flowing vapor from the cyclone collectors back to the upstream end of the processing tube. The pulse combustor includes a rotary valve, a combustion chamber, an inner tail pipe and an outer tail pipe. The combustion chamber and inner tail pipe are conical and tubular sections mounted in longitudinal compression, and the compressive forces are transmitted externally across the junction of the combustion chamber and tail pipe by a strongback assembly. The rotary valve includes first, second, and third closely adjacent cylinders defining an interior air chamber. The cylinders have radially oriented, substantially aligned apertures which define an air intake.

Abstract: An incinerator has a furnace body whose height is 1.5-10 times the average internal diameter thereof. A combustion chamber is included which is formed by providing a plurality of air blast ports in a lower side wall and/or bank in the furnace body. A gas exhaust port is provided in the upper side of the combustion chamber and the side wall of the upper portion of the furnace body. A duct is included for leading an exhaust gas from the exhaust port to a place for making secondary use thereof.

Abstract: A fluidized bed combustion apparatus has a gas dispersion plate provided in a lower part of a fluidizing chamber on which fluidizing mediums are fluidized to form a fluidized bed in which a fuel is combusted. The apparatus further includes a porous ceramic member so mounted in a combusted gas outlet of the fluidizing chamber as to transverse the outlet. Coating materials having a high radiation rate are applied on an inner wall surface of the fluidizing chamber and on the porous ceramic member surface directed to the fluidizing chamber. The porous ceramic member is perforated with holes each having a diameter larger than a particle diameter of a fluidizing medium. The apparatus is equipped with a unit for back-washing the filter. The apparatus also includes a plate, provided downwardly of the filter, for capturing the particles scattered from the fluidized bed.

Abstract: A fluidized-bed reactor composed of modular steel castings is assembled from a support frame, a sliding frame and reactor housing segments on the frames so as to be able to withstand the temperatures and temperature gradients to which the reactor may be subject.

Abstract: A method for the heat treatment of finely granular material, particularly for the manufacture of cement, employs a preferably multi-stage cyclone preheater (2), a rotary tubular kiln (1), a cooler (6) and a kiln off-gas line (5) which is formed between rotary tubular kiln (1) and cyclone preheater (2). The off-gas lines provides a passage substantially in upward direction for the off-gases of the rotary tubular kiln (1) and receives tertiary air fed thereto for the combustion of additional fuel. The tertiary air is provided in two streams from the cooler (6), which cooler is connected behind the rotary tubular (1) on the material side, the streams being introduced into the kiln off-gas line (5) at different heights. In order to separate the combustion of the additional fuel from the precalcination and to avoid the production of injurious nitrogen oxides (NO.sub.

Abstract: A bed 26 of particulate material is moved in a band continuously along an annular path by passing fluid media having both circumferential and vertical components through the bed along that path. The fluid media comprises combustion gases which are passed through the bed along a portion of the path for heating the particulate material as it passes therethrough and fluid matter to be heated which passes through the bed along another portion of its path such that the fluid matter is heated as it passes through the particulate material which has been heated by the combustion gases.

Abstract: The invention provides a circulating fluidized bed apparatus comprising a housing and a pair of spaced partitions located within the interior of the housing. The partitions are spaced from each other to define a draught zone therebetween having a lower inlet and an upper outlet. Separate fluid feed arrangements are provided for feeding separate fluidizing fluids into the housing for fluidizing particulate material in the draught zone and for fluidizing particulate material outside the draught zone. Above the draught zone the housing has a fluid outlet arrangement for fluidizing fluid from the draught zone, and a fluid outlet arrangement for fluidizing fluid from the housing outside the draught zone.

Abstract: The invention relates to a method and to apparatus for the heat treatment of fine-grained material using a calcination zone which is arranged between a preheating zone and a final combustion zone, and after passing through the calcination zone a proportion of the material is introduced into exhaust air from the cooling zone and delivered therewith back to the calcination zone for the purpose of recirculation. In this way a good burn-out of the fuel used in the calcination zone and a high degree of deacidification of the material are achieved.

Abstract: A pulse combustion energy system including a pulse combustor coupled to a processing tube for flowing material to be processed therethrough, the processing tube being coupled to a pair of cyclone collectors for receiving the material flowing therefrom. An optional recycling section is coupled to the cyclone collectors for flowing vapor from the cyclone collectors back to the upstream end of the processing tube. The pulse combustor includes a rotary valve, a combustion chamber, an inner tail pipe and an outer tail pipe. The combustion chamber and inner tail pipe are conical and tubular sections mounted in longitudinal compression, and the compressive forces are transmitted externally across the junction of the combustion chamber and tail pipe by a strongback assembly. The rotary valve includes first, second, and third closely adjacent cylinders defining an interior air chamber. The cylinders have radially oriented, substantially aligned apertures which define an air intake.

Abstract: A fluidized bed reactor in which a bed of solid particulate material including fuel is provided in a furnace section and air is introduced into the bed at a velocity sufficient to fluidize the particulate material and support the combustion of the fuel. A separator separates the entrained particulate material from a mixture of the air and the gaseous products of the combustion. The separator is connected to the furnace section for returning the separated particulate material back to the bed. Relatively coarse sorbent and relatively fine sorbent material are passed into the furnace section at two separate locations, respectively.