Abstract: The present invention relates to a hydraulic reactor and classifier, with ultrasonic application for a continuous process of separation and recovering minerals or other type of materials or for the production of chemical compounds. It comprises a body of two main sections, an upper part and a lower part. The upper part comprises a container, a loading compartment, a lamella package, at least one ultrasound transducer package and a peripheral weir. The lower part comprises an inverted semi-pyramidal container having a square base, the square base attached to the upper part, at least one ultrasound transducer package at different location within the reactor to distribute the ultrasound effect all over the slurry flowing through the reactor, a nozzle for delivering a liquid or a gas. The final part comprises a pinch valve for discharging coarse particles as a slurry.
Type:
Grant
Filed:
October 17, 1997
Date of Patent:
September 7, 1999
Assignee:
Servicios Condumex
Inventors:
Belisario Sanchez Vazquez, Jesus Gutierrez Bastida, Ulises Monter Valenzuela, Arturo Zamudio Guzman, David Rascon Chavez, Timoteo Pastrana Aponte, Salvador Garcia Garcia
Abstract: This invention pertains to the use of a combination of polyvalent cations, clay dispersant and high molecular weight anionic polymer to preferentially remove colloidal fines (slimes) from a kaolin slurry, leaving the remainder of the kaolin in the slurry in the form of a coherent gelatinous mass.
Type:
Grant
Filed:
July 11, 1997
Date of Patent:
August 17, 1999
Assignee:
Engelhard Corporation
Inventors:
Mitchell J. Willis, Sanjay Behl, Raymond H. Young
Abstract: A fecal parasite concentrator which has a cylindrical body (20) with connections for a sample vial (24) on one end having a protective recess (27) for receiving the sample vial and a centrifuge tube (28) on the other. An integral filter (36) is disposed within the body at right angles coaxially covering the cross sectional area of the hollow body. The filter contains a series of closely spaced square openings for filtration of a liquid diluted fecal specimen. A hollow stem (40) with truncated end (44) extends upwardly from the filter having orifices (46) which permit air to pass therethrough when the diluent specimen flows through the filter.
Abstract: A method and apparatus for reclaiming component plastics from a mixture of plastics wherein differentials in specific gravity serves as the segregation mechanism. The method includes the steps of: (1) fragmenting the plastic articles such that the resulting plastic fragments are generally of a preferred dimension and contain primarily one such component plastic; (2) sizing the fragmented plastic so as to remove plastic fragments which do not comport to the preferred dimensions; (3) adding a fluid medium to the plastic fragments to produce a slurry; (4) loosening contamination from the plastic fragments; (5) segregating the heavy and light components within the slurry based on specific gravity; (6) isolating the segregated plastic fragments; and (7) cleaning the heavy and light components to produce high purity plastic.
Abstract: In an apparatus for classifying objects by sedimentation having a straightening passage, capable of being prevented adhesion of bubbles to the straightening passage, and capable of being prevented a sample supplying error generated caused by a closed sample supplying portion on account of air locking, there is provided a bubble-removing passage for removing the bubbles within fluids at upper stream position of a straightening mesh within a classifying bath for classifying objects based on dropping position caused by a final sinking velocity of said objects falling within fluids after throwing said objects into flowing fluids, the bubble-removing passage which comprises a filter and a filter holder secured within the classifying bath through a protuberance.
Abstract: A tube-type sample supplying portion 1 is provided upright above a classification tank 2. A sample inlet pipe 5, which communicating with a culture tank 3, is connected to the lower part of the sample supplying portion 1. An outlet pipe 6, which communicating with the culture tank 3, is connected to the upper part of the sample supplying portion 1. A sample feed pump 4 and a valve 7 are positioned in one of the flow passages between the outlet pipe 6 and the culture tank 3. The flow speed of the fluid including the sample in the sample supplying portion 1 is set to a speed being only a little faster than the final sinking speed of lumps of immature cultivated cells in the fluid.
Abstract: A fecal parasite concentrator which has a cylindrical body (20) with connections for a sample vial (24) on one end and a centrifuge tube (28) on the other. An integral filter (36) is disposed within the body at right angles coaxially covering the cross sectional area of the hollow body. The filter contains a series of closely spaced square openings for filtration of a liquid diluted fecal specimen. A hollow stem (40) with truncated end (44) extends upwardly from the filter and a number of geometrically shaped orifices (46) permit air to pass therethrough when the diluant specimen flows through the filter.
Abstract: The invention proposes using liquefied carbon dioxide as a separation agent for flotation and/or sedimentation separation, which is particularly suitable for separating foodstuff mixtures such as meat components, because it can be maintained in liquid phase at the freezing point of water and is inert with respect to many substances of the mixture. By controlling the pressure and/or the temperature at values of about 26 bar and -14.degree. C., the density of the separation agent can be adjusted to correspond to that of water so that water containing substances of the mixture can be readily separated.
Abstract: The present invention provides a sorting method and a sorting device for sorting particles according to their settling velocities in a fluid medium. According to one aspect, the sorting method comprises admitting particles into a longitudinally vertically positioned container containing a fluid and allowing the particles to settle for a specified period of time under the influence of gravitational forces resulting in separation of the particles according to their settling velocities, followed by rotating the container by 90 degrees in order for the container to take a longitudinally horizontal position and thus allowing the separated particles to settle down and be collected in a sorted fashion. The sorting device comprises a container and means for achieving sorting of particles using this sorting method.
Abstract: A process is taught for separating heterogeneous plastic material into homogeneous fractions, which comprises:a. feeding the plastic material in a triturated form to a first water-containing separation tank to separate the high specific weight products from the low specific weight products;b. recovering the mixture of high specific weight products from the bottom of said first separation tank and drying them in a first drier;c. treating the resulting mixture with a chemical agent capable of swelling/modifying the plastic materials which are sensible to said chemical agent; andd. drying the products so treated and feeding them to a second separation tank, in which the nonswollen/nonmodified plastic material precipitates while the remaining material, maintained on the surface, is discharged.
Type:
Grant
Filed:
August 1, 1991
Date of Patent:
September 21, 1993
Assignee:
Centro Sviluppo Settori Impiego S.r.l.
Inventors:
Annibale Vezzoli, Marino Lamperti, Francesco Milani, Bruno Albrisi
Abstract: A method for the separation and recovery of foils, in particular aluminum foils, and the other components in waste foil-containing laminates includes subjecting the waste laminates to agitation in a heated polyalkylene glycol polymer solution. The thus heated mixture is cooled to permit density variations to separate the plastic and paper components of the waste laminate from the foil components therein. The separated foil components can be recovered from the polyalkylene glycol polymer solution for recycle or other use. Using a polyalkylene glycol polymer solution permits recovery of the glycol polymer in a heated recovery tank to recycle the polymer to facilitate further foil separation while minimizing adverse effects on the environment.
Abstract: A method is provided for recovering PVC from a material including PVC and one or more non-PVC components, in which the material is mixed with a sufficient amount of a plasticizer at an effective temperature, preferably in the range of 100.degree.-200.degree. C., to give a PVC: plasticizer ratio such that the PVC and plasticizer form a mixture which is a liquid at that temperature so that the liquid PVC/plasticizer can be separated from the non-PVC component or components.
Abstract: The present invention provides a method for selectively separating co-mingled materials of different densities by selective density flotation of the materials in a fluid in the vicinity of its critical point. The extermely high compressibility of a fluid in the vicinity of its critical point allows continuous variations over the maximum density range to be accomplished using minimal changes in temperature and pressure. Materials exhibiting similar densities can thus be separated by adjusting the fluid density to a point between the two materials.
Abstract: The present invention relates to processes for purifying impure psyllium husk using fluorinated hydrocarbons and the psyllium husk having greater than about 99% purity prepared by these processes.
Abstract: A flotation separator has a tank normally partially filled with a liquid, and an endless conveyor belt with upper and lower courses extending from a lower portion in the tank to a higher discharge position exterior to the tank. A shroud isolates the lower course of the belt from the upper course within the liquid, and from the primary circulation in the tank.
Abstract: This invention relates to a process for the dynamic separation of mixtures of materials, such as minerals having different specific gravities, by using one dense medium having two different densities, the process includes a closed loop flow system utilizing two medium streams of two different densities for separating mixtures of materials into two material/dense medium streams. The dense material is recovered from the two material/dense medium streams after separation and splitting by creating two return streams of two different densities which are individually fed to a tub, and the two medium streams are formed from the dense medium of the tubs by effecting overflow of the dense medium between the two tubs to establish substantially equal volume therebetween and maintain equal volume therebetween.
Abstract: The present invention relates to a method for the separation of a mixture of plastic particles and contaminant. According to the invention, a two-phase solution composed of a halogenated hydrocarbon and water are applied to the mixture of plastic and contaminant. The two-phase solution and mixture are placed in a separator. The two-phase solution and mixture are rotated in the separator. During rotation, the plastic contained in the mixture of plastic and contaminant, which has a density less than the halogenated hydrocarbon contained in the two-phase solution, is separated by gravitation from the contaminant and carried by the water of the two-phase solution. Also during rotation, the contaminant contained in the mixture of plastic and contaminant, which has a density greater than the halogenated hydrocarbon of the two-phase solution, is separated by gravitation from the plastic and carried by the halogenated hydrocarbon of the two-phase solution.
Abstract: The invention relates to apparatus for the elutriation of particles of a Ziegler-Natta type alpha-olefin polymerization catalyst, based on transition metal compound(s) and preferably also comprising magnesium compounds, by means of an elutriation liquid which is a non-polar liquid, for example a hydrocarbon chemically inert in relation to the catalyst. The apparatus comprises a tank (M2) for the preparation of the catalyst suspension and the elutriation column or columns (F1), (F2).
Abstract: A process for coal cleaning providing a method of cycloning fine particle coal for cleaning the cola of ash and pyrites, the method including steps of demoisturizing the coal by immersing the coal in an elevated temperature, non-aqueous liquid and cycloning the coal in a non-aqueous, agglomerate inhibiting carrier liquid.
Abstract: An apparatus for separating a slurry into phases containing larger and smaller grains has an upright tank in which a plurality of downwardly extending inlet pipes open at their lower ends between outlets for the coarse and fine phases located at the bottom and top of the tank, respectively. At the lower end of each inlet pipe, an upwardly widening frustoconical cup is provided with a bottom confronting the open end of the inlet pipe to deflect the slurry upwardly and outwardly. Within the cup swirl vanes impart a swirl to the slurry.
Type:
Grant
Filed:
February 25, 1985
Date of Patent:
April 14, 1987
Assignee:
Magyar Aluminiumipari Troszt
Inventors:
Jozsef Harsanyi, Zoltan Kiss, Ferenc Kukonya, Janos Pinter, Alajos Suri, Andras Toth
Abstract: A method and apparatus for separating discrete solid fractions from dispersion in a dense liquid medium wherein the suspended materials are subjected to settling to produce a low density fraction floating on the surface, a middlings fraction suspended in the liquid medium, and a high density fraction which sinks to the bottom. The high density fraction is lifted off in a region of the dense medium in which the surface level of the dense medium is substantially free from particles of the floating low density fraction.
Abstract: A process for separating porous components from non-porous components of a mixture of granular materials comprising the steps of:(a) contacting the mixture of the porous and non-porous materials with a gas capable of adsorbing in the pores of the porous component;(b) discharging the so charged or loaded mixture into a liquid in which the adsorbed gas is allowed to desorb from the porous componet, the viscosity and surface tension of the liquid being chosen so that the desorbed gas remains attached to the porous component with the specific gravity of the liquid chosen to separate the so desorbed porous component from the nonporous component; and(c) separating the floating materials from those of sinking materials in the liquid of Step (b).
Abstract: A process for enhancing coal by removing the gangue (rock, shale, iron pyrites and the like) associated with the mined coal as it comes from the crushers before further treatment. The process described slurries the crushed run of the mine (ROM) coal with a heavy medium, such as perchloroethylene, for a short period of time at ambient or below temperatures, (i.e. slurry times of 5-30 minutes and temperatures of 90.degree. C. to below -10.degree. C.); thereafter allowing, in a substantially quiescent environment, the solids to settle or float as their inherent densities are greater or lesser respectively than the density of the heavy medium. After settling the float solids (mostly coal of lower sulfur and ash content) are separated from the heavy medium as one stream and the sink solids (mostly the gangue) as a second stream. These solids are each washed with hot (90.degree. C.-100.degree. C.) water and the vapor azeotrope which forms from the water and heavy medium mixture (azeotrope) removed.
Abstract: Sink/float separation of finely divided mixtures of scrap plastics and non-plastics materials, such as metal and glass, by addition of a liquid halogenated hydrocarbon being substantially chemically inert towards the components of the mixture, having essentially no swelling or dissolving effect on the plastics components and having an intermediate density adapted to the densities of the plastics and non-plastics components, preferably a chlorofluoro-substituted aliphatic hydrocarbon, such as 1,1,2-trichloro-1,2,2-trifluoroethane, and then the resulting non-sedimented and sedimented fractions are separated and, if desired, subjected to further separation treatments, while the halogenated hydrocarbon is recycled.The process is non-destructive and particularly useful for separation of finely divided scrap wire, glass or cable, such as PVC/Cu, rubber/Cu, PEX/Al, PVC/Al, PE/Cu or mixtures thereof.
Abstract: There is disclosed the process for the separation of the clay particles (ash) from coal particles by the use of two immiscible liquids followed by the separation and removal of the liquids from the solids.
Abstract: A method of separating lighter and heavier particles in a solids mixture includes entraining the mixture in a liquid of a specific gravity intermediate the specific gravities of the lighter and heavier particles, and feeding the liquid through a first opening into one end of a rotating vessel. The vessel is designed so that the liquid attains a dynamic equilibrium at which an annular, centrifugally-induced, substantially static, revolving volume of the liquid of stable internal surface is confined by the vessel about the axis of rotation, while further liquid flows on within the stable internal surface. Heavier particles are centrifugally directed into the annular volume, while lighter particles remain entrained in on-flowing liquid which flows out a second opening in the other end of the vessel.
Type:
Grant
Filed:
December 6, 1983
Date of Patent:
August 6, 1985
Assignee:
The Broken Hill Proprietary Company Limited
Abstract: A method for cleaning fine coal is provided which includes: mixing the coal with a fluid of such a specific gravity that clean coal particles would float while refuse particles would sink therein, pretreating the coal-fluid slurry by adding a surfactant, subjecting the mixture to ultrasonic dispersion, and separating the entire mixture into higher and lower specific gravity fluid streams by means of centrifugal separation. The fluid of the chosen specific gravity and the surfactant may be recovered from the fluid streams and recycled if desired.
Abstract: This invention discloses a method of enriching raw oil shale by crushing and pulverizing raw oil shale or similar oil bearing materials into smaller, lean oil particles and larger, oil rich particles; floating the larger, oil rich particles in a heavy media organic liquid which causes the oil rich lighter particles to float on the surface and causes the heavier, mineral containing particles to sink. The floating larger, oil rich particles thus obtained contain increased percentages of oil bearing constituents.
Abstract: An improved process for making metallurgical coke is provided which enables the use of coals that ordinarily do not yield coke of expected stability based on the rank of the coal. The comminuted coal is pretreated by contacting and reacting the coal with a halogenated hydrocarbon liquid, particularly perchloroethylene, and the pretreated coal is thereafter subjected to high temperature carbonization.
Type:
Grant
Filed:
April 11, 1983
Date of Patent:
July 9, 1985
Assignee:
Inland Steel Company
Inventors:
William DuBroff, Dennis D. Kaegi, Jerome J. Knoerzer, Elliott Y. Spearin
Abstract: A method of manufacturing silicon nitride whiskers in which a carbon and silicon containing material having a thin configuration and sufficient porosity to permit both the passage of a gas therethrough and to provide spaces for growing whiskers therein is charged on a gas-permeable tray, and heated in a furnace of non-oxidizing atmosphere. The tray is moved intermittently through a series of temperature zones, increasing stage-by-stage from about 400.degree. C. to 1,300.degree. C., while a non-oxidizing gas is circulated through the porous material to remove any impurities. Thereafter, the heated tray is intermittently moved through a series of increasing temperature stages from about 1,350.degree. C. to 1,450.degree. C. in the presence of a flow of nitrogen gas to effect whisker growth. The heat-treated silicon nitride-containing material is dispersed in a two-phase mixture of a hydrophobic organic liquid and water. The desired silicon nitride whiskers can be isolated from the aqueous phase.
Abstract: A method for separation of seeds, in which the seeds are incubated in a suitable environment and then dried to produce a pronounced difference in moisture content between filled-dead seeds and filled-viable seeds. These two seed fractions are then separated from each other by utilizing the moisture content difference.The seed fractions may e.g. be separated from each other by placing seeds in a liquid the density of which is somewhat lower than the density of viable seeds but higher than the density of filled-dead seed. In such a case the filled-dead seeds will float up whereas the viable seeds sink.
Abstract: The channel in a sedimentation field flow fractionation apparatus is improved by the use of a heavy liquid layer formed of a water immiscible, chemically inert, nontoxic material. This thin, heavy liquid layer prevents the sample from plating on the outer channel wall thereby permits a less perfect finish to be formed and to some degree corrects lack of circularity of the channel. Where multiple channels are used, the use of this layer reduces leakage between adjacent channels.
Abstract: Particulate materials of different density are separated from one another by placing them in non-reactive liquefied gas of intermediate density whereby the lighter material floats and the heavier material sinks. A pressure field may be established in the liquefied gas to enhance the particulate separation process. The method is especially suited for separating and removing oxide and other particulate contaminants from metal and alloy powders.
Abstract: Washing tank for separating particles differing the specific gravity by means of a liquid separatory medium using the float-and-sink method. The washing tank is provided with at least one collecting tray for removing the settled particles, which collecting tray can be reciprocated along the bottom of the washing tank and in the first extreme position is about centrally on the bottom of the washing tank, where it can collect settling particles, and in the second extreme positions rests on the edge of the washing tank, so tilted that settled particles contained in it can slide into a discharge device positioned next to the washing tank. Preferably, the washing tank is provided with two alternating collecting trays hingingly attached to arms fixed on a horizontal shaft swinging to and fro between two extreme positions.
Abstract: A new heavy liquid parting medium comprising an emulsion of water and a substantially water immiscible heavy parting liquid for use in beneficiating ores by gravity separations such as sink-float processes. The specific gravity of the emulsion parting medium can be adjusted by proportioning the relative amounts of water and the substantially water immiscible heavy liquid. As-mined coal is beneficiated using a water-trichlorofluoromethane emulsion as the parting medium in a sink-float separation process.
Abstract: A continuous system for separating acceptable from unacceptable synthetic rubber seals and other parts according to their specific gravity comprising a tank having a flotation chamber and an exit or collection chamber. Fluid of a given specific gravity such that the acceptable parts will float therein enters the flotation chamber in such a manner as to produce a rolling or turbulent flow therein. The rolling flow agitates the parts to liberate entrapped air therefrom permitting the parts true buoyancy to float the acceptable parts or sink the unacceptable parts. The floating parts are then swept over an outlet weir into a collection basket by means of a two dimensional fluid flow over said weir.
Abstract: A method for determining the efficiency of float-sink raw material separation units which achieve separation by specific gravity sorting of raw material in particle form introduced to a liquid bath. The efficiency is determined by introducing to the bath, with the raw material in particle form for separation, prepared particles of determined size and specific gravity and detecting the separation location of these prepared particles.
Type:
Grant
Filed:
December 5, 1980
Date of Patent:
August 24, 1982
Inventors:
Joseph W. Leonard, III, Joseph W. Leonard, IV
Abstract: An elongated rectangular open frame table supports a rectangular sump tank open at its top and mounted below the top of the open frame and spaced from the ends and the rear of the frame. A recessed sink is formed by inclined table sink drain sheets which extend from the rear and sides of the sump tank to the table top. A pivotable first lid overlies the open top of the table frame to seal off the recessed sink and the sump tank. A removable second lid overlies the open top of the sump tank to selectively close off the recessed sink volume from the sump tank. Air register openings provided within the rear table sink drain sheet adjacent the sump tank connect via a vertical tubular ducts, to an underlying main air tube subjected to low vacuum pressure for removing toxic vapors from the recessed sink during the performance of separation tests on coal submerged within liquid provided to the sump tank.
Abstract: Pyrite is removed from coal by crushing, air classification and organic heavy medium separation. A superior method is taught wherein only a fraction of the total coal treated need be treated with organic media separation.
Abstract: This invention provides a process and system for the segregation of used catalyst contaminated by the extended processing of hydrocarbon feedstocks. It utilizes multi-stage fluidization and segregation of the catalyst in an upflowing liquid, and recovery of the less contaminated catalyst upper fraction for reuse. The recovery vessel comprises at least two concentric compartments, either or both of which may preferably be tapered so as to provide less cross-sectional area at the upper end of the catalyst bed for improved fluidization of the used catalyst. The used catalyst material is usually introduced into the annulus between the vessel walls, and the lower density less contaminated fraction is accumulated within the inner compartment, from which it is withdrawn for reuse.
Abstract: The transporting of solids using selected fluorochlorocarbons as carriers. Techniques of recovering the carrier are also disclosed as are novel solids handling and processing systems in which the compositions employed as carriers are also used to effect a heavy liquid resolution of solids.
Abstract: The present invention is directed to silicon carbide whisker recovery from a mixture of silicon carbide whiskers and carbonaceous silicon carbide particles. The invention involves shredding the mixture down to a specified size, dispersing the mixture in water to form an aqueous mixture, mixing in an effective amount of flocculating agent, agitating the aqueous mixture, mixing the aqueous mixture with an immiscible organic liquid, agitating the resulting water-organic liquid mixture, allowing settling of the aqueous mixture and organic liquid so as to establish two liquid phases, separating the two liquid phases into an organic liquid phase and an aqueous phase and, lastly, performing a solid-liquid separation on the aqueous phase, thereby obtaining from the aqueous phase the desired silicon carbide whiskers.
Type:
Grant
Filed:
October 9, 1979
Date of Patent:
March 17, 1981
Assignee:
Silag, Inc.
Inventors:
Ponisseril Somasundaran, Kavssery P. Ananthapadmanabhan
Abstract: A method of beneficiating coal in which the coal is conditioned by agitating it in the presence of a dense halogenated hydrocarbon and a surface active agent to effect a transfer of surface water from the coal to mineral matter associated therewith and an agglomeration of the mineral matter and to envelop the coal in a film of the surface active agent. The conditioned coal is then introduced into a halogenated hydrocarbon bath having a specific gravity intermediate those of the coal and the mineral matter. The agglomerated mineral matter sinks to the bottom of the bath in the region of feedstock introduction, and the coal disperses in and migrates to the top of the bath.
Abstract: Processes for recovering coal from a particulate composite in which the composite is mechanically worked in the presence of an agglomeration promoting additive and in an aqueous carrier to effect a separation of the particles of coal in the composite from mineral matter associated therewith, a coalescence of the coal particles into product coal agglomerates, and a dispersion of the mineral matter in the aqueous carrier. The product coal agglomerates are resolved into their particulate constituents, and the latter are subjected to a density differential separation which effects a separation of that material in the agglomerates which has a relatively low mineral matter content and a high coal content from that having a higher content of mineral matter.
Abstract: Coated nuclear fuel particles are produced by batchwise deposition of several pyrolytic carbon and/or silicon carbide layers on fuel particles wherein the first layer is a porous pyrolytic carbon layer and wherein the coated particles are subsequently sieved and/or sized. The process comprises fractionaling all of the coating batches according to the geometric density by the hydrostatic method of weighing by buoyancy after placing all batches in heavy liquids and selecting for further working up into fuel elements only the particle fraction which has a geometric density whose boundary value deviates from the average density by less than .+-.20%.
Abstract: A waterless method of separating minerals and a mobile mineral separator are described in which preheated mine products are continuously separated from associated mine refuse by sink/float washing in a heavy-liquid bath which has been heated to its boiling point. The heavy liquids will usually be halogenated organic liquids or liquid mixtures. The separated product and reject fractions are withdrawn by augers to drainage hoppers where most of the heavy liquids are removed for return to the bath. Final removal of the heavy liquids from the mine products and reject fractions is accomplished by vaporization as the product and the reject fraction move by additional augers through heated pipes. The vaporized heavy liquids are collected in air-cooled or otherwise cooled condensers and are returned to the bath. The heavy liquids are essentially completely recycled.
Abstract: The float-sink separation of coal from pyrite and ash in a bath of liquid SO.sub.2 is disclosed. The specific gravity of the bath may adjusted by the addition of inert materials such as miscible materials or finely divided solids. Additional separation in another dense medium may be employed. The communition, conveying and mining of coal with liquid SO.sub.2 is also disclosed.
Abstract: A method used in conjunction with prospecting or mineral exploration of sedimentary deposits containing a minute amount of an economic mineral is described. The method is applied to a bulk sample of a deposit and generally involves the steps of washing and wet sieving the sample to produce two or more size fractions, drying the size fraction, separating at least one size fraction into at least two specific gravity fractions and, usually, magnetically separating at least one specific gravity fraction for the purpose of obtaining economic mineral concentration in at least one fraction of such sample. For specific environments where unstable sulphide conditions exist, an acid leach step may be included following specific gravity separation either to a specific gravity fraction or to a fraction resulting from magnetic separation after specific gravity separation.
Abstract: A method of using fluorinated hydrocarbons as a carrier to convey mined coal to a separation station. The carrier acts as a parting liquid for beneficiating the coal. The carrier is recovered and returned to the mine for conveying more coal. Some of the returned carrier may be used at the mining face as a dust suppressant. Ash from burning the coal may be returned with the carrier where it is disposed of as waste material.
Abstract: A process for preparing coal for use as a fuel. Forming a coal-water slurry having solid coal particles with a particle size not exceeding about 80 microns, transferring the coal-water slurry to a solid bowl centrifuge, and operating same to classify the ground coal-water slurry to provide a centrate containing solid particles with a particle size distribution of from about 5 microns to about 20 microns and a centrifuge cake of solids having a particle size distribution of from about 10 microns to about 80 microns. The classifer cake is reground and mixed with fresh feed to the solid bowl centrifuge for additional classification.
Type:
Grant
Filed:
August 25, 1989
Date of Patent:
November 5, 1991
Assignee:
The United States of America as represented by the United States Department of Energy
Inventors:
Mukund K. Venkatachari, August D. Benz, Horst Huettenhain