Abstract: An apparatus and method for separating contaminating particles from an incoherent mass of woody material. The apparatus comprises a separation chamber into which the incoherent mass is introduced, first blowers associated with the separation chamber, to deliver a first flow of air in a direction substantially transverse to the direction of fall of the incoherent mass, and to divert the direction of fall of the woody materials and/or vegetable fibers with at least a first specific weight from the heaviest contaminants materials with a second specific weight, and dividing members disposed inside the separation chamber, in order to define different passage channels. The apparatus comprises first suction means associated with the first blowers, to perform a further separation on the woody and fiber materials with first specific weight. The apparatus comprises second blowers disposed so as to perform a third separation on a first part of the materials already separated by the first blowers.

Abstract: A method and apparatus for the extraction of particles from surfaces is disclosed. A preferred method comprises the steps of (1) adjusting the temperature and humidity of an air supply to provide an adjusted air supply, (2) directing a blast from the adjusted air supply to a surface bearing particles, so as to produce a deflected blast that comprises some of the particles from the surface, (3) collecting the deflected blast and particles, and (4) directing the deflected blast and particles towards an analyzer. A preferred apparatus includes an air adjuster and a probe comprising an adjusted air supply passage, an adjusted air aperture, a deflected air aperture, and a deflected air passage, wherein the air adjuster is adapted to provide a flow of adjusted air to the adjusted air supply passage and the adjusted air aperture. The flow may be continuous, intermittent, pulsed or periodic.

Abstract: In an extraction device comprising a suction apparatus (16) with an electric motor (32) and an centrifugal separator (14) exhibiting an inlet cylinder (22), a vertically arranged dip pipe (30) and a lateral suction nozzle (24) through which a laden gas stream enters the inlet cylinder (22), it is provided with a view to creating a low-cost and easy-to-handle extraction device of a compact design, having a centrifugal separator, that the electric motor (32) is arranged inside the dip pipe (30).

Abstract: A separation system includes an air separator that in one embodiment primarily receives Municipal Solid Waste (MSW) containing relatively light MSW recyclable materials such as paper, cardboard, plastic containers, and/or metal containers. The air separator blows the relatively light MSW recyclable materials up though a chamber and onto a first conveyer while the other relatively heavy MSW material drops down a chute onto a second conveyer. A separation screen receives the relatively light MSW recyclable materials from the air separator and separates the relatively flat paper and cardboard from the plastic and metal containers.

Abstract: A classifier for classifying particulates entrained in a flowing stream of gas is configured such that a change of direction of gas flow causes particles to impinge upon a target, heavier particles being trapped in a downwardly extending fluidized trap. The classifier is easily constructed, has no moving parts, and can take the place of sifters and other equipment traditionally used for classifying such product streams.

Abstract: An apparatus for segregating particulate by density and/or size including a fluidizing bed having a particulate receiving inlet for receiving particulate to be fluidized. The fluidized bed also includes an opening for receiving a first fluidizing stream, an exit for fluidized particulate and at least one exit for non-fluidized particulate. A conveyor is operatively disposed in the fluidized bed for conveying the non-fluidized particulate to the non-fluidized particulate exit. A collector box is in operative communication with the fluidized bed to receive the non-fluidized particulate. There is a means for directing a second fluidizing stream through the non-fluidized particulate as while it is in the collector box to separate fluidizable particulate therefrom.

Abstract: A separator of solids for separating first and second solids, the diameter and density of the first solids being larger than the diameter and density of the second solids. A first substantially vertical internal baffle (2) forms a passage in the low portion of the separator and forms two compartments (1A, 1B) on the passage of the fluidized solids. The fluidization of each compartment is independently controlled by two fluidization gas inlets (3A, 3B) in order to obtain the desired velocity field for separating the first and second solids in the first compartment (1A) and discharging the second solids through a vent (8), as well as for transferring the first solids into the second compartment (1B).

Abstract: A cart is towed behind a combine harvester for collecting corn cobs and includes a conveyer belt feeding into a system for separating cobs from residue to be discharged and a tank for receiving and transporting the cobs. An unload auger is provided from the tank to one side of the cart while the cart moves forward. Power for driving the cart is obtained from a chopper drive of the combine harvester. The separating arrangement includes a series of sequential blower fans for blowing air through the discharged material as it is discharged from a conveyor and into a spreading guide disperses the residue. The cobs are conveyed using a series of augers where the auger to flight distance is at least 2 inches and particularly a pair of augers feed the cobs through a front wall of the tank so as to push cobs upwardly into the tank.

Abstract: The invention relates to processing particulates and apparatus therefor. More specifically, the invention is directed to processes and apparatus for separating particulates. According to various aspects of the invention, particulate separation processes and apparatus are provided comprising flowing a particulate over a foraminous wall and through a sieve.

Abstract: A compact housing for a dedusting apparatus utilizes a magnetic flux field to disrupt the static charge attracting dust particles to product particles, which along with fluidization and counter current airflow principles that are proven to dislodge dust particles from the product, provides a highly efficient, compact deduster. The housing supports a double wash deck with product flow separated between the back-to-back primary wash decks. A deflector directing the flow of product onto the primary wash decks is provided with an extension that extends parallel to the wash deck to eliminated product bouncing off of the wash deck. The lower air outlets are eliminated, while the upper air outlets are positioned in extensions to the main housing above the product inlet opening. Air flow through the Venturi zone is enhanced by re-directing clean air directly to the backside of the Venturi panels, thereby eliminating the extraneous by-pass boxes.

Abstract: A classifier for classifying particulates entrained in a flowing stream of gas is configured such that a change of direction of gas flow causes particles to impinge upon a target, heavier particles being trapped in a downwardly extending fluidized trap. The classifier is easily constructed, has no moving parts, and can take the place of sifters and other equipment traditionally used for classifying such product streams.

Abstract: A method for the extraction, separation, fractionation and purification of biopolymers from plant materials using supercritical and/or subcritical solvent extractions is disclosed. Specifically, the process can be used for the separation of resins and rubber from guayule shrub (Parthenium argentatum), and other rubber and/or resin containing plant materials, using supercritical solvent extraction, for example supercritical carbon dioxide extraction. Additionally, polar and/or non-polar co-solvents can be used with supercritical carbon dioxide to enhance the selective extraction of resins and rubbers from the shrub.

Abstract: Process for pre-concentration of recoverable polymer materials formed from residues from grinding consumer durable goods at the end of their lives such as automobiles, computer equipment and household appliances, consisting of treating the residue by steps in sequence consisting of screening, aeraulic separation, grinding and ultimate aeraulic separation, to eliminate the major part of contaminating materials from them, such as metals, glass, rubber, sand or others in order to obtain a fraction pre-concentrated in recoverable polymer materials by recycling. The pre-concentration process is a means of reaching preferably at least 85% by weight of recoverable polymer materials by recycling.

Abstract: The invention relates to a closed air circulation system for an apparatus used for sorting wood chips, containing chips in a variety of sizes and/or fines particles, in a wood chips processing chamber, in separate fractions by means of a gas flow, which is delivered from one or more nozzle chambers by way of a nozzle slit into the wood chips processing chamber and which applies an impulse action to the processing-bound wood chips sliding along an inclined support surface. Air is circulated from the wood chips processing chamber by way of a dedusting cyclone into said one or more nozzle chambers. The wood chips processing chamber is maintained at a negative pressure by regulating the volume of air removed from the chamber. A conduit extending between the wood chips processing chamber and the one or more nozzle chambers is open to the ambient atmosphere.

Abstract: An electrostatic separation apparatus for conductive particles and insulating particles with reduced separation time and improved separating capability, comprises a substantially flat-plate shaped bottom electrode (26) provided on lower side, a substantially flat-plate shaped mesh electrode (22) provided above the bottom electrode (26) as spaced a predetermined distance apart from the bottom electrode (26) and having a number of openings (24) to allow particles to pass therethrough, a direct current power supply connected to at least one of the mesh electrode (22) and the bottom electrode (24), and a voltage is applied across the bottom electrode (22) and the mesh electrode (24), thereby forming a separation zone (10) between the electrodes.

Abstract: A two-stage dynamic classifier (30, 30?) for classifying a pulverized feed material (34, 34?, 38) entrained in an air flow (31) includes a vertically extending housing having a lower feed material inlet (18), an upper feed material outlet (24), a processing section (47, 47?) disposed between the feed material inlet and the feed material outlet, and a lower tailings discharge (26). A classifier conditioner (32) is disposed in a lower portion of the processing section and a turbine classifier (42, 44) is disposed in an upper portion of the processing section.

Abstract: The invention relates to an air separator for sifting material suspended in a flow of gas having course material and fine material by using a sifting wheel which rotates in a sifting chamber and which has blades fixed on the external periphery thereof. The blade channels are cross-flown radially from the outside by gas containing the suspended fine particles. The oversized particles are rejected before reaching he internal end of the blade canal. The flow of fine particles is guided through the blade channels in a forced manner in a plurality of consecutive layers in the direction of the axis of rotation. The arrangement in layers of the flow of fine particles after it leaves the blade channels remains in place until it leaves the sifting chamber.

Abstract: The invention is an automatic debris separation process for effecting air separation of fragmented materials, such as size-reduced fiber feedstocks derived from textile wastes. The process uses high-velocity air within an elutriation assembly to efficiently remove ferrous and non-ferrous metal debris from recyclable polymer fibers. In particular, the process may employ automatic process control strategies to vary airflow within the elutriation assembly in process-controlled response to measured metal contamination, thereby ensuring that post-separation metal contamination is maintained at or below an upper contamination limit.

Abstract: The invention is an automatic debris separation system for effecting air separation of fragmented materials, such as size-reduced fiber feedstocks derived from textile wastes. The system uses high-velocity air within an elutriation assembly to efficiently remove ferrous and non-ferrous metal debris from recyclable polymer fibers. In particular, the system may employ automatic process control strategies to vary airflow within the elutriation assembly in process-controlled response to measured metal contamination, thereby ensuring that post-separation metal contamination is maintained at or below an upper contamination limit.

Abstract: A longitudinal micrometric separator for the classification of solid particulate materials comprising an outer casing having an inflow opening and an outflow opening for the particulate material, a collection chamber at the bottom, as well as a sliding support for the particulate material extending substantially along a longitudinal drawing axis, in which the material is conveyed in the direction of the aforesaid longitudinal axis by a forced fluid flow. The sliding support comprises at least one first inclined wall, lying in a plane parallel to the drawing axis, and at least one dropping channel with axis parallel to the drawing axis and connected to a side end of the same inclined wall, the other side end of the inclined wall being set at a distance from the internal surfaces of the casing.

Abstract: In a method and a system for sorting shredder residues of metal-containing wastes, in particular of body shells, where shredder residues are separated into a shredder light fraction and a non-ferromagnetic fraction (shredder heavy fraction), the method and the system having corresponding arrangements provide that (a) during the sorting of the shredder light fraction and the shredder heavy fraction in preliminary processes and a main process, a crude-sand fraction is produced by separating out at least a ferromagnetic fraction, a fraction containing nonferrous metals, a fiber fraction, and a granulate fraction, and (b) in a refining process, the crude-sand fraction is separated into a residual fraction rich in organics, a dust fraction containing heavy metals, a sand fraction depleted in organics and metals, and a metallic fraction, using the sequential process steps of density separation and metal separation.

Abstract: A two-stage dynamic classifier (30, 30′) for classifying a pulverized feed material (34, 34′, 38) entrained in an air flow (31) includes a vertically extending housing having a lower feed material inlet (18), an upper feed material outlet (24), a processing section (47, 47′) disposed between the feed material inlet and the feed material outlet, and a lower tailings discharge (26). A classifier conditioner (32) is disposed in a lower portion of the processing section and a turbine classifier (42, 44) is disposed in an upper portion of the processing section.

Abstract: Methods and apparatus are provided, which separate out at least a portion of fine dust, including fluoride, from recycled alumina. The difference in natural drop velocity and flow properties of fine and coarse particles is used to effect the separation.

Abstract: A centrifugal separator (1) for separating particles from gas comprises a separator chamber (10) having an upper portion (12) with at least three substantially vertical planar walls (12A, 12B, 12C) with perpendicular inner faces, and a lower portion (14), means for defining therein in the chamber a vertical gas vortex. that comprise The gas vortex has an inlet (18) for gas to be dedusted formed in the vicinity of a first corner (C1) between said first and second walls for gas to be dedusted, an outlet (22) for dedusted gas. and an outlet (15, 20) for separated particles. The separator comprises an acceleration duct with a first transverse section at the first end of the duct that is distinctly greater than a second cross section at the second end. This second end (15B) is connected to said the inlet for gas to be dedusted at the first corner, while forming an obtuse angle with said the second wall, and is inclined downwardly in a direction towards the separator chamber.

Abstract: A compact cascade impactor is formed to classify particles carried in a flow through the impactor. The impactor has collection chambers that are arranged to conserve space and yet provide a large flow passageway. The collection chamber may be tear drop shaped and being nested together.

Abstract: A grain dropping passage constituted below a husking unit (D) serves as a winnowing room (A). A winnowed grain conveyor (1) is provided as the sole conveyor below the winnowing room (A). A winnowing wind blown by a winnowing fan (F) through a blowing room (B) passes through below the winnowed grain conveyor (1) and then rises in the winnowing room (A). The grains mixed with hulls and others are winnowed in the winnowing room (A) so as to be sorted into two kinds: winnowed grains to be received by the winnowed conveyor (1), and the other including hulls to be received by a hull conveyor (2) arranged oppositely to the winnowed grain conveyor (1) with respect to the winnowing fan (F). In this manner, powerful separation can be executed by means of winnowing wind having a large amount and large speed so as to improve a winnowing ability remarkably.

Abstract: A cleaning system is disclosed for cleaning contaminants from animal litter. In a first embodiment of the invention, a vacuum and a blower are coupled together and configured so that the blower blows a first fluid stream into animal litter simultaneous with the vacuum drawing a second fluid stream from the animal litter. Relatively light contaminants are drawn into the vacuum while the relatively heavy animal litter is left behind. In a second embodiment of the invention, a cyclonic separator is used to draw the animal litter and the intermixed contaminants into the cyclonic separator simultaneously, and separate the animal litter from the contaminants. The animal litter is returned to the area from which it was removed. In a third embodiment of the invention, mechanical agitation is coupled with air separation to further enhance separation of contaminants from the animal litter.

Abstract: A pneumatic weighing device has a weigh pan, which is supported for vertical movement by a load cell in response to the weight of an article; the weigh pan is provided with a plenum chamber having an apertured upper surface through which air under pressure is directed for purpose of providing an air cushion for supporting and transporting articles to be weighed. The weighing device additionally includes pneumatic means for rejecting articles of improper weight.

Abstract: Volatile compounds may be economically recovered from solids present in aqueous solution by subjecting the solution to rapid separation where the volatilization occurs in a flash, spray, or fluid bed, or mechanically agitated dryers. Rapidly separating the solids from the volatile compound greatly simplifies the isolation of the volatile compounds from water. The methods have utility for fermentation processes, solids management, and recycling processes.

Abstract: A self-cleaning separator is described for cohesive or adhesive solids from a fluidborne stream of solids on the basis of a cyclonelike separation. The separator consists at least of a cylindrical upper section (8) having a separating chamber (3), a product inlet (2), a fluid outlet (5), and of a conical lower section (6) having a solids outlet (7) adjoining below the lower section (6), at least the side wall (4) of the upper section (8) being produced from an elastic material, in particular an elastomeric material.

Abstract: A compact cascade impactor is formed to classify particles carried in a flow through the impactor. The impactor has collection chambers that are arranged to conserve space and yet provide a large flow passageway. The collection chamber may be tear drop shaped and being nested together. The impactor includes nozzles that are used across a desired flow range without changing the nozzles.

Abstract: A system for transporting wet chips to a centrifugal separator where the wet chips are separated into dry chips and fluid with the dry chips being transported to a dry chips site and the fluid recirculated or collected. Preferably, the centrifugal separator, when actuated, serves to generate a pneumatic flow of air through a wet chip conduit whereby the wet chips are pneumatically conveyed to the separator from a source of origin such as a tooling machine station where wet chips are generated. A parts separator may be located at either end of the wet chip conduit.

Abstract: In order to create a sifting device with integrated static sifter member and dynamic sifter member having at least one rotatably disposed rod basket such that the two sifter members are optimally coordinated so as to operate efficiently, particularly with moist sifting material to be dried, it is proposed in accordance with the invention to have a bypass line leave from the intermediate area between the static member and the dynamic member of the sifting device for drawing off a partial flow of the sifting air flow/sifting gas flow and to supply only the remaining outgoing sifting air of the static sifter member (static cascade sifter or V-sifter) to the dynamic sifter member with the at least one rotatably disposed rod basket.

Abstract: Two-stage classification of a granular material, in particular a cement grinding feed, is accomplished in two classifiers connected in series in such a way that the separative behavior or the separative action and thus the particle-size distribution of the undersized or finished material coming from the second classifier can be modified with simple resources. Part or all of the oversized material of the second classifier is recycled to the second classifier.

Abstract: The performance of a gravity separator is enhanced by providing a magnetic material on the separation surface of the gravity separator. A magnetically enhanced gravity concentration/separation apparatus is provided for enhancing separation of a target feed material from remaining feed materials in a feed mixture having a transport medium and feed materials which comprise the target feed material and the remaining feed materials. The target feed material is magnetic and generally has a higher specific gravity than any magnetic feed materials contained in the remaining feed materials. The separating apparatus comprises a gravity separator including a separation surface on which to flow the feed mixture.

Abstract: The method for air classification of toner used to develop electrostatic images, whereby a toner product consisting of a powder with a wide particle size distribution is converted into a higher-quality toner product with a narrow particle size distribution in that the residence time of the toner product is controlled by means of components, components which in the upper section of the classifying chamber quickly introduce the toner product in a homogeneous state into the classifying chamber, which in the central section of the classifying chamber permit a longer residence time of the toner product, and which in the bottom section of the classifying chamber permit rapid discharge of the toner product from the classifying chamber, all of which makes it possible to produce a toner end product with an extremely narrow particle size distribution.

Abstract: A cyclone separator (1) has an elongated vertical housing (2), whose upper section (3) is equipped with a carrier gas/product inlet (4), a separating wheel (6), and a carrier gas/fine product discharge (7). A lower section (9) of the housing defines an oversized product discharge (11). The housing (2) has a central axially extending built-in unit (12), which separates the cyclone carrier gas/particle flow stream, downwardly in a peripheral region, and upwardly in a central region. A lower built-in unit section (14) is joined to a cylindrical middle built-in unit section (15). An entry area of the middle section (15) is equipped with a constrictor (19) which with the built-in body forms a Venturi. Finally, a secondary air supply (24) enters into a lower inlet opening (9) of the lower built-in unit section (14) facing the constrictor (19). An injector effect is achieved which increases the suction, resulting in further improvement of the separating and sorting properties.

Abstract: There is described a process for cleansing contaminants, such as oil, PCB, PAH, heavy metals and the like, from a heterogeneous material, such as sand, gravel, earth, oil gravel, asphalt, drill borings ("kaks") and the like. More specifically the invention relates to a process comprising the steps: i) that a sorption agent is added to the material, and that the material and the sorption agent are mixed/kneade sufficiently for a considerable portion of the contamination to be extracted from the material and absorbed by the sorption agent, and that ii) thereafter the sorption agent is separated from the material on the basis of specific gravity/particle size by means of an applied flow of gas, so that the sorption agent is led with the flow and can be collected in a separate fraction.

Abstract: An apparatus for pneumatically conveying granular material such as gravel. The apparatus includes a vehicle base mounting plate, a prime mover such as a diesel engine, a hydraulically driven air blower, a hopper for receiving gravel to be conveyed, and a hydraulically driven auger assembly for moving gravel from the hopper to a pneumatic pick-up point. After pneumatic pickup, the gravel is transported through an extended network of suitable pneumatic tubing such as low friction, thick wall, PVC pipe sections, to a desired discharge location, where the material is discharged into a catch can for downward placement at a desired point. In a preferred embodiment, the auger assembly comprises a three piece unit, with a shaft, an inner auger section, and an outer auger section. The outer auger section is a replaceable wear part which can be repaired, rebuilt, or replaced as necessary due to frictional wear on the auger due to contact with the solid being conveyed.

Abstract: A method of separating diced water-bearing fruit of desired size from undersize slivers, loose seeds and pieces of skin in a diced fruit mix. The diced fruit mix is fed into an upwardly moving gaseous stream which removes loose and loosely adhering residual peel from the dice and carries the residual peel, loose seeds and undersize slivers above the select dice. The select dice is recovered from the gaseous stream separately from the residual peel, seeds and slivers. The method is particularly well suited for producing select tomato dice of desired size from tomato dice containing residual tomato peel and loose tomato seeds. The tomato dice is obtained by dicing whole tomatoes which have been peeled in a mechanical peeler. The method also can be used to separate diced water-bearing vegetable pieces of desired size from a vegetable mix containing undersize slivers of the vegetable.

Abstract: Apparatus for separating lighter particles such as lamina containing little or no stem from tobacco particles contained in threshed leaf tobacco which comprises a plurality of tobacco particle separating units, each including a separation chamber each a fan system for establishing a generally upward air flow therein. A tobacco particle projecting mechanism is provided in each chamber for projecting tobacco particles across the generally upward air flow therein with each having structure for directing tobacco particles in cooperating relation therewith to be projected thereby. Mechanisms are provided for receiving the lighter particles carried upwardly by the air flow, the heavier particles moving downwardly within the air flow within each chamber and discharging the particles therefrom.

Abstract: A machine for sorting recyclable matter includes a trommel for conducting and screening an input flow of recyclable matter and a magnetic mechanism coupled to the trommel for extracting magnetic material from the input flow while the trommel rotates. The input flow is dropped vertically from the trommel into a positive-pressure air separator which separates the flow into a first material stream including lightweight articles and a second material stream including relatively heavy articles. The heavy articles of the second material stream drop downwardly in the air separator. Padded baffles are provided in the air separator for reducing the downward velocity of the second material stream, which substantially lowers breakage of glass articles.

Abstract: An apparatus and method for irradiating PTFE particles to cause them to disintegrate into a powder includes a chamber into which the particles are fed continuously. The particles are simultaneously agitated using only air, irradiated with a beam of electrons and pulverized. The powder produced thereby is extracted using an air classifier.

Abstract: A multi-stage cyclone for fluidized catalytic cracking of heavy oils is disclosed. A low efficiency inertial separator concentrates solids, FCC catalyst and fines, by forcing gas and entrained solids to make from 1/2 to 3/4 turn. Gas, with most of the solids content removed, is charged directly into the inlet horn of a conventional high efficiency cyclone. The solids concentrator/cyclone device may be used in FCC regenerators or reactors to reduce particulate losses, reduce catalyst attrition, and reduce erosion of cyclones caused by high catalyst loadings.

Abstract: A method and apparatus for the simultaneous irradiation, grinding, agitation and air cooling of fluoropolymers, such as polytetrafluoroethylene, produce dry lubricants. An air classifier is used to extract particles of a uniform size during the process.

Abstract: A separator device for separating out heavy materials from metal chips and lubricant, in which the separaton may be viewed by an operator while the separation process is in operation at a drop-out opening in the separator. The invention further permits heavy, undesired objects to be separated in an open chute first member whereas second stage separation is accomplished by a substantial fluid pressure sufficient to entrain chips and lubricant and transport the entrained chips and lubricant along the length of a second chute member to a centrifuge where the lubricant is separated from the chips.

Abstract: The impurity laden particulate material to be cleaned by a gravity feed deduster is passed through a magnetic field of varying intensity to neutralize the static charge causing the impurities to adhere to the primary product. The material is then subjected to air flows to separate the neutralized debris from the primary product. The air flows can be of high velocity and can be either pressurized air or vacuum induced. The cleaned product is collected and the contaminated air is treated to recover the debris therefrom.

Abstract: A spray drier (1) for the preparation of powders, agglomerates or the like, by the drying of pumpable products, has at an inlet (6) of its exhaust discharge line or lines (7) for the drying gas used in its drying chamber (3), a wind sifter (9) with a rotating bucket wheel (10). The flow generated by the rotating bucket wheel (10) of the wind sifter (9) acts against the exhaust suction flow. The discharge of fine materials is directed into the exhaust line (7) and the coarse material discharge (8) takes place in the drying chamber (3). Consequently, excellent desired separation of the coarse material component from the fine material component can be obtained within the drying chamber.

Abstract: An improved pneumatic plant-blade-from-stem separator, including an upright box having an intermediate separating chamber with an inlet for material to be separated. Beneath the box an air inlet and an outlet mouth are provided, between which a discharge plane is disposed at an angle descending toward the outlet mouth. The plane is provided with a fixed bed comprising a plurality of longitudinally extending stock of square cross-sectional shape movable so as to define slots therebetween which are transverse to the bed.

Abstract: A foreign object removal system is disclosed including a removal chamber projecting laterally from the combustion chamber of a fluid bed reactor and connected via a downwardly directed pipe to a material flow control plenum chamber, which includes means for fluidizing the mixture of inert bed particles and foreign objects at the bottom of the pipe for lateral movement into an air classifier, wherein the foreign objects are dropped to a collection tank and the fluid bed particles are carried upwardly by a stream of classifying air to a deentrainment chamber where their velocity is reduced and they are returned to the combustion chamber.