Processes Patents (Class 209/164)
  • Patent number: 5916446
    Abstract: Process and apparatus for the separation of solid matter via flotation. The flotation process for the separation of solid matter from a suspension takes place via the utilization of centrifugal forces wherein the suspension is brought into rotation in a separating zone so that the floated components are particularly effectively routed to and concentrated at the center of the separating space, whereby, when viewed axially, floated components and the remaining portion of the suspension is guided in the same direction and out of the separating zone, with the avoidance of vortexes in the flow stream achieving particularly favorable separation effects. In addition, several apparatuses, for carrying out the process, are also set forth.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: June 29, 1999
    Assignee: Sulzer-Escher Wyss GmbH
    Inventors: Herbert Britz, Alexander Peschl
  • Patent number: 5910254
    Abstract: A process for dewatering an aqueous suspension of microalgae is disclosed in which the aqueous suspension of the algae is introduced into a bubble column or a modified bubble column for generating a froth of bubbles and adsorbed algal cells that can be separated from the aqueous suspension. In one advantageous embodiment, the bubble column is a multi-stage loop-flow flotation column that has three loop-flow zones, each of which is defined by a draft tube concentrically mounted in the column to divide each loop-flow zone into a riser and the downcomer. Fine bubbles of gas and brine are in cocurrent upward flow in the riser and in cocurrent downward flow the downcomer. A higher gas holdup is promoted in the riser than in the downcomer, thereby circulating the brine in loop-flow upwardly through the riser and downwardly through the downcomer. Liquid communication between adjacent loop-flow zones is substantially eliminated. A froth enriched in algae is generated that can be separated from the aqueous suspension.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: June 8, 1999
    Assignee: Eastman Chemical Company
    Inventors: Scott Arthur Guelcher, Jeffrey Scott Kanel
  • Patent number: 5909022
    Abstract: A flash flotation device (1) comprises a tank (2) to contain slurry (3) incorporating minerals to be extracted, a feed inlet (25) for admission of slurry (3) into the tank (2), agitation means (10) to agitate the slurry (3) within the tank (2), aeration means to aerate the slurry (3) whereby floatable minerals in suspension form a surface froth for removal via froth lip (29), a bottom outlet (26) for withdrawal of relatively coarse or dense components of the slurry (3) from the tank (2), and a side outlet (28) to regulate the level of slurry (3) in the tank (2).
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: June 1, 1999
    Assignee: Outokumpu Mintec Oy
    Inventors: Peter Bourke, Jouko Kallioinen
  • Patent number: 5902976
    Abstract: Improved control for the separation of waste materials, or materials having waste components, is provided by the injection of air, or other gas bubbles, into a water-filled tank while simultaneously depositing the waste containing material to be separated onto the top of the water. This method is especially useful where both portions of some or all of the materials to be separated from each other have specific gravities greater than that of pure water. The rapidly rising air bubbles provide turbulence and buoyancy to materials that are slightly heavier than water, such as water-soaked organic products, but do not prevent heavier materials, such as sand and metals from sinking. An apparatus is described which allows for the removal of both the floating and sinking fractions from the floatation tank.
    Type: Grant
    Filed: January 30, 1998
    Date of Patent: May 11, 1999
    Inventor: Donald R. Beasley
  • Patent number: 5900604
    Abstract: The present invention is a process for recovering valuable minerals using air lift concentration and progressive ore reduction. The ore is ground to a relatively coarse size, the ground ore is classified, and the underflow fraction floated to produce concentrate, middlings, and tailings fractions. The middlings fraction can be reground to liberate the valuable minerals and subjected to further air lift concentration. The classifier overflow fraction is passed through additional classifiers, the underflow fractions of which can be reground and refloated. The overflow fraction of the last classifier can be subjected to flotation to further enhance recovery.
    Type: Grant
    Filed: March 18, 1997
    Date of Patent: May 4, 1999
    Inventor: Harry L. McNeill
  • Patent number: 5876558
    Abstract: The present invention provides a froth flotation process for the separation of paper and wood fibers from printed and copying inks and other contaminants during the recycling of paper. A liquid solution containing a frothing agent is applied from the top of a froth flotation device, preferably in the form of a spray, to the upper surface or portion of an aqueous pulp slurry present in the device, or of a froth phase produced in the device, prior to or during the froth flotation process.
    Type: Grant
    Filed: December 17, 1997
    Date of Patent: March 2, 1999
    Assignee: Institute of Paper Science and Technology, Inc.
    Inventors: Yulin Deng, Junyong Zhu
  • Patent number: 5855769
    Abstract: Hydrophobic material is selectively separated from an aqueous feed by forming gas bubbles in a flow of the feed, forming hydrophobic material/gas bubbles aggregates by motionless mixing and separating the aggregates as a froth by use of centrifugal action.
    Type: Grant
    Filed: August 14, 1996
    Date of Patent: January 5, 1999
    Assignee: Commonwealth Scientific and Industrial Research Organisation
    Inventors: Bruce Andrew Firth, Philip Kwadwo Ofori
  • Patent number: 5840179
    Abstract: Processes for treating fly ash to enhance the fly ash as a pozzolan for portland cement mixes and to separate therefrom a substantial carbon compound and/or to increase the fineness of the fly ash include the treatment of a fly ash slurry with ultrasonic energy using ultrasonic horns immersed in a slurry of fly ash and water and imparting to said slurry such ultrasonic energy as to cause microscopic cavities to form and implode with high localized energy to break up fly ash agglomerations along cleavage lines and to break up carbon particles and matrices which have entrapped fly ash microspheres therein to release the microspheres into the slurry. A conditioner agent may be added at or during ultrasonic treatment to enhance the flotation of the carbon compound.
    Type: Grant
    Filed: March 17, 1998
    Date of Patent: November 24, 1998
    Assignee: JTM Industries, Inc.
    Inventors: Rafic Y. Minkara, Jerry L. Heavilon
  • Patent number: 5814210
    Abstract: A method and apparatus are disclosed for the microbubble flotation separation of very fine and coarse particles, especially coal and minerals, so as to produce high purity and high recovery efficiency. This is accomplished through the use of a flotation column, microbubbles, recycling of the flotation pulp, and countercurrent wash water to gently wash the froth. Also disclosed are unique processes and apparatus for generating microbubbles for flotation in a highly efficient and inexpensive manner using either a porous tube or in-line static generators.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: September 29, 1998
    Assignee: Virginia Tech Intellectual Properties, Inc.
    Inventors: Roe-Hoan Yoon, Gregory T. Adel, Gerald H. Luttrell
  • Patent number: 5807479
    Abstract: The present invention provides a process that employs both non-selective flotation and oxidative leaching of the resulting concentrates to recover an increased amount of copper from porphyry copper ores. The non-selective flotation step uses collectors and conditions, such as pH, that are conducive to the strong flotation of sulfide minerals generally. In the oxidative leach, the copper sulfide minerals in the concentrate fraction are oxidized to copper compounds, which are soluble in the leach solution. The oxidative leach includes the use of ammonia and sulfite under agitation leaching conditions to convert the copper sulfide minerals into ammonia soluble forms.
    Type: Grant
    Filed: July 14, 1995
    Date of Patent: September 15, 1998
    Assignee: COPROCO Development Corporation
    Inventor: Nathaniel Arbiter
  • Patent number: 5795484
    Abstract: An ultra-fine coal particle fraction forms a coal product with particles that are dilatant due to the mechanical stripping of the clay contaminates from the coal surface and the subdividing of the clay to clay platelets which are peptized to maintain discreetness in an aqueous slurry. The coal particles are unflocculated and can produce an aqueously permeable barrier on a sieve. The ultrafine coal product has an increase of 100-150 BTU per pound and when combusted reduced Nox production of 20-40% is realized. In a 15.times.0 micron coal fraction, the sulphur content is significantly reduced.
    Type: Grant
    Filed: May 8, 1995
    Date of Patent: August 18, 1998
    Inventor: Edward H. Greenwald, Sr.
  • Patent number: 5776349
    Abstract: Methods are disclosed for dewatering an aqueous suspension of microalgae, especially Dunaliella salina, with a Jameson cell. The algal cells are ruptured sufficiently to promote froth flotation of the cells from the suspension. The algal suspension is introduced into the top of the Jameson cell downcomer and passed through an orifice plate therein to generate a free liquid jet of the suspension. The jet is plunged downwardly through a gas and the gas is transported with the jet through a gas and liquid interface into the algal suspension. The momentum of the jet is dissipated, which disperses the gas into fine bubbles. The fine bubbles are intimately contacted with the aqueous suspension in cocurrent downward flow in a collection zone to absorb the algal bodies onto the surfaces of the bubbles. A froth of bubble and algal agglomerates is formed and collapsed to obtain a dewatered algal concentrate.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: July 7, 1998
    Assignee: Eastman Chemical Company
    Inventors: Scott Arthur Guelcher, Jeffrey Scott Kanel
  • Patent number: 5762781
    Abstract: A flotation apparatus including: an elongate vertical riser (142) in which a cocurrent flow of gas/slurry liquid mixture rises upwards to a discharge mouth at its top end; an aeration unit (140) provided at a lower end of the riser; a separation unit (150) provided at the top end of the riser; and wherein the height of the riser is selected to produce substantially turbulence free flow in which a high gas lift occurs in the riser such that a pressure drop between the liquid inlet and the discharge outlet of the aeration unit is sufficient to produce gas particle dispersion and recirculation of the slurry liquid through the flotation apparatus.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: June 9, 1998
    Assignee: Atomaer Pty. Ltd.
    Inventor: George Bodnaras
  • Patent number: 5702612
    Abstract: A flotation method and apparatus for separating a selected constituent from an effluent of an industrial process is provided. The apparatus includes a conditioning tank and a flotation cell. The conditioning tank allows mixing a flotation reagent with an effluent and includes a mechanism for also dissolving gas in the effluent within the conditioning tank. The flotation cell includes a dissolved gas flotation chamber having an overflow for recovering the selected constituent and a tailings drain. In addition, the flotation cell also includes an added gas flotation chamber having a sparger for injecting gas into the effluent, an overflow for recovering the selected constituent and a tailings drain.
    Type: Grant
    Filed: July 20, 1995
    Date of Patent: December 30, 1997
    Assignee: University of Kentucky Research Foundation
    Inventor: Xiang-Huai Wang
  • Patent number: 5690812
    Abstract: Process and apparatus for the separation of solid matter via flotation. The flotation process for the separation of solid matter from a suspension takes place via the utilization of centrifugal forces wherein the suspension is brought into rotation in a separating zone so that the floated components are particularly effectively routed to and concentrated at the center of the separating space, whereby, when viewed axially, floated components and the remaining portion of the suspension is guided in the same direction and out of the separating zone, with the avoidance of vortexes in the flow stream achieving particularly favorable separation effects. In addition, several apparatuses, for carrying out the process, are also set forth.
    Type: Grant
    Filed: November 2, 1995
    Date of Patent: November 25, 1997
    Assignee: Sulzer-Escher Wyss GmbH
    Inventors: Herbert Britz, Alexander Peschl
  • Patent number: 5685899
    Abstract: Kaolin clays are conditioned for the removal of colored titaniferous impurities by (A) first mixing the kaolin clay with a collector to condition the impurities, in the absence of a dispersant, but in the presence of sufficient water to yield a mixture having a solids content of at least 65 percent by weight and (B) then deflocculating the kaolin clay mixture at a pH of at least 4.0 with a dispersant in amounts sufficient to yield a kaolin clay slurry which is suitable for subsequent processing to remove colored titaniferous impurities.
    Type: Grant
    Filed: July 28, 1995
    Date of Patent: November 11, 1997
    Assignee: Thiele Kaolin Company
    Inventors: Joseph Allen Norris, Jorge L. Yordan
  • Patent number: 5672267
    Abstract: A method and apparatus for separating particulate material. The method includes the steps of delivering a substantially constant supply of feed to a first aerator, aerating the substantially constant supply of feed in the first aerator, introducing the substantially constant supply of aerated feed to a flotation vessel below a froth/liquid interface within the vessel, so that floatable particulate material entrained by air bubbles from the first aerator can float upwardly to the froth/liquid interface. Air is introduced into the liquid phase in the flotation vessel via a second aerator located below the level at which the aerated feed is introduced into the flotation vessel, so that floatable particulate material not entrained by air bubbles from the first aerator, may be entrained by air bubbles from the second aerator, as the air bubbles from the second aerator rise upwardly through the liquid phase to the froth/liquid interface.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: September 30, 1997
    Assignee: Multotec Cyclones (PTY) Limited
    Inventor: Nardus Terblanche
  • Patent number: 5660718
    Abstract: A suitably conditioned slurry feed is introduced to a trough from which it is distributed into a slurry layer-flow forming chamber provided with a discharge weir which discharges an evenly spread layer of slurry onto an inclined plate feeding into a mixing passage and then into a vessel. Recirculated slurry from the vessel is also fed into the mixing passage via a recycle gate which forms it into a layer of slurry. An array of clean liquid jets accelerates thin gas envelopes and impinges between layers of slurry and causes intensive mixing of all streams in the mixing passage. A high shear rate produces high intensity turbulence and shears gas into very small bubbles. A multiphase mixture flow is discharged from the mixing passage into the vessel, where it flows past one or more longitudinal stabilizing baffles. Gas bubbles loaded with hydrophobic particles disengage from the stream, rise toward the liquid surface and are diverted by bubble-diverting guides toward a froth discharge end of the vessel.
    Type: Grant
    Filed: September 13, 1995
    Date of Patent: August 26, 1997
    Assignee: M.D. Research Company Pty, Ltd.
    Inventors: Michael Wenzel Chudacek, Stephen Henry Marshall, Charles Harold Warman
  • Patent number: 5653867
    Abstract: An improved method is provided for separating acrylonitrile butadiene styrene (ABS) and high impact polystyrene (HIPS) plastics from each other. The ABS and HIPS plastics are shredded to provide a selected particle size. The shredded particles of the ABS and HIPS plastics are applied to a solution having a solution density in a predefined range between 1.055 gm/cm.sup.3 and 1.07 gm/cm.sup.3, a predefined surface tension in a range between 22 dynes/cm to 40 dynes/cm and a pH in the range of 1.77 and 2.05. In accordance with a feature of the invention, the novel method is provided for separating ABS and HIPS, two solid thermoplastics which have similar densities by selectively modifying the effective density of the HIPS using a binary solution with the appropriate properties, such as pH, density and surface tension, such as a solution of acetic acid and water or a quaternary solution having the appropriate density, surface tension, and pH.
    Type: Grant
    Filed: March 19, 1996
    Date of Patent: August 5, 1997
    Assignee: The University of Chicago
    Inventors: Bassam J. Jody, Bayram Arman, Dimitrios E. Karvelas, Joseph A. Pomykala, Jr., Edward J. Daniels
  • Patent number: 5601703
    Abstract: The present invention is directed to a type of flotation machine that combines three separate operations in a single unit. The flotation machine is a hydraulic separator that is capable of reducing the pyrite and other mineral matter content of a coal. When the hydraulic separator is used with a flotation system, the pyrite and certain other minerals particles that may have been entrained by hydrodynamic forces associated with conventional flotation machines and/or by the attachment forces associated with the formation of microagglomerates are washed and separated from the coal.
    Type: Grant
    Filed: December 5, 1995
    Date of Patent: February 11, 1997
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Kazimierz Szymocha, Boleslaw Ignasiak, Wanda Pawlak, Conrad Kulik, Howard E. Lebowitz
  • Patent number: 5578198
    Abstract: The automatic regulator device comprises a channel for measuring the level and density of pulp in the chamber of a floatation machine, in which two bubbling pipes are in communication with a differential pressure pickup connected to the input of a frother flow-rate regulating channel and to one input of a correction unit whose other input is connected to a pressure pickup communicating with one of the bubbling pipes. The output of the correction unit is connected to the input of a circuit designed to regulate the rate of flow of water with frother in a pulp level stabilizing channel, the output of said circuit being connected to an actuator valve installed on a pipeline feeding water with frother and furnishing a control signal with respect to a pulp level deviation from a preset value.
    Type: Grant
    Filed: September 21, 1990
    Date of Patent: November 26, 1996
    Assignee: Yakutsky Nauchno-Issledovatelsky I Proektny Institut Almazodbyvajuschei Promyshlennosti
    Inventors: Fedor A. Chumak, Vladimir N. Cherednik, Mikhail N. Zlobin
  • Patent number: 5573658
    Abstract: A low brightness pigment and method is provided from a heretofore rejected waste kaolin stream. Kaolin processing rejects are high in iron-stained TiO.sub.2. After separating the stained TiO.sub.2 from the high brightness kaolin and concentrating the resulting fraction, the material can be processed to produce a low brightness pigment suitable of many applications where lower brightness is desirable, such as coating paper board without mottling.
    Type: Grant
    Filed: December 28, 1994
    Date of Patent: November 12, 1996
    Assignee: J. M. Huber Corporation
    Inventors: Albert C. Kunkle, Robert E. Hardy, Bobby R. Skipper
  • Patent number: 5571422
    Abstract: The present invention concerns a reactor for removing impurities from a liquid, in particular for de-inking, including a tank (1) within which the liquid to be purified together with a gas or air is introduced (2-3); a drain of the purified accepted through an outlet (7) of said tank (1); inlets (8-11, 9-12, 10-13) at different heights of the tank (1) connected to said purified liquid outlet (7) together with the inlet of gas or air; a rotating shaft (18) inside the tank (1) carrying blades (20, 21, 22, 23) at the different heights of the tank within which the liquid together with gas or air is introduced; the blades (20, 21, 22, 23) have progressively increasing heights when moving towards the lower portion of the tank (1). The invention also concerns the method embodied by the above-described reactor.
    Type: Grant
    Filed: June 12, 1995
    Date of Patent: November 5, 1996
    Assignee: Comer S.p.A.
    Inventor: Flavio Magaraggia
  • Patent number: 5551574
    Abstract: A method for the separation of components of a slurry by froth flotation are provided. The apparatus includes a flotation column having a slurry feed for introducing slurry into the flotation column, a bubble generator for generating bubbles of gas at the bottom of the flotation column and a froth overflow at the top of the flotation column for collecting and discharging a froth fraction of the slurry. The central portion of the flotation column includes a plurality of vertically-spaced tail ports disposed alternately on opposite sides of the flotation column for discharging a non-float fraction of the slurry. In addition, a single, fluid-impermeable baffle having at least two edges is associated with each tail port. The baffles are of sufficient size to block the vertical flow in at least 50% of the horizontal cross-sectional area of the flotation column to thereby create a quiescent flow zone in the area of each tail port, wherefrom the non-florable fraction of the slurry is removed.
    Type: Grant
    Filed: September 18, 1995
    Date of Patent: September 3, 1996
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventors: Gary W. Hicks, William L. Cornell
  • Patent number: 5544759
    Abstract: The invention relates to a method and an apparatus for the separation of hydrophobic substances by froth flotation that basically consists of feeding pulp in the form of a thin layer on at least a lower gas-permeable slanted surfaces in which low pressure gas is injected generating small bubbles that collect hydrophobic particles. The froth containing concentrate is separated and washed before removal in a froth reservoir formed by a lower gas-permeable slanted surface and a wall at its lower end. At the top of the wall, the froth overflows to a launder for removal. At the bottom of the wall, the pulp containing the tailings discharges through an opening. Froth washing is performed by means of baffles that force the froth to flow underneath water sprays.
    Type: Grant
    Filed: April 5, 1995
    Date of Patent: August 13, 1996
    Inventor: Daniel F. Urizar
  • Patent number: 5522510
    Abstract: An apparatus for separating impurities from coal, includes a device for removing a predetermined amount of ash-forming substances from the coal and a device for removing a predetermined amount of high specific gravity (e.g., pyrite) from the coal having been processed by the ash-forming substance removing device. The ash-forming substance removing device and the high specific gravity material removing device each possess characteristics that allow them to more efficiently reject different types of mineral impurities from coal.
    Type: Grant
    Filed: June 14, 1993
    Date of Patent: June 4, 1996
    Assignee: Virginia Tech Intellectual Properties, Inc.
    Inventors: Gerald H. Luttrell, Roe-Hoan Yoon
  • Patent number: 5511669
    Abstract: A flotation device (1) which includes a tank (2) to contain a slurry (3) incorporating minerals which are to be extracted. Aeration of the slurry (3) by suitable structure in the device produces a zone (11) of mineralised froth above the slurry (3). A launder (15) directs the mineralised froth away from the tank (2). At least one porous diffusion surface (16) in direct contact with the froth dispenses a washing liquid directly into the froth zone (11).
    Type: Grant
    Filed: September 2, 1994
    Date of Patent: April 30, 1996
    Assignee: Supaflo Technologies Pty. Ltd
    Inventor: Peter G. Bourke
  • Patent number: 5512133
    Abstract: A method for producing substantially ink-free pulp from recycle printed paper comprising first pulping the recycle paper in a hydrapulper with at least water and an agglomerating agent thereby producing a pulp. Ink particle agglomerates in the pulp are then removed by screening the pulp through at least one screen and by cleaning the pulp in a cyclone cleaner. Pulp together with small ink particles that escape the prior separation stages is then conducted from the cyclone cleaner through a standpipe at a consistency of about or less than 1% where particles of ink associate with small air bubbles and are elevated to the surface of the pulp where they accumulate as a froth which may be removed by overflowing.
    Type: Grant
    Filed: August 1, 1994
    Date of Patent: April 30, 1996
    Assignee: International Paper Company
    Inventor: Larry D. Markham
  • Patent number: 5482535
    Abstract: In a process for the recovery of silver by flotation from the residue from the wet extraction of zinc, the residue from the neutral wet extraction of zinc, the residue from the neutral wet extraction of zinc is recovered and is subsequently ground in an attritor and the residue which has been ground in an attritor is subjected to a flotation.
    Type: Grant
    Filed: July 12, 1994
    Date of Patent: January 9, 1996
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventors: Ali-Nagi Beyzavi, Horst Dittmann, Friedrich Rosenstock
  • Patent number: 5460270
    Abstract: Middlings from the primary separation vessel ("PSV") are recycled through a line to the PSV. The middlings are aerated with fine air bubbles using in line eductor/aerator assemblies. The aerated middlings are mixed as they are pumped through a line back to the PSV. Bitumen recovery from the PSV is increased as a result.
    Type: Grant
    Filed: September 1, 1993
    Date of Patent: October 24, 1995
    Assignees: Alberta Energy Company Ltd., Canadian Occidental Petroleum Ltd., Esso Resources Canada Limited, Gulf Canada Resources Limited, Her Majesty the Queen in right of the Province of Alberta, as represented by the Minister of Energy and Natural Resources, HBOG-Oil Sands Limited Partnership, PanCanadian Petroleum Limited, Petro-Canada Inc., Mocal Energy Limited
    Inventors: Edward W. Chan, Robert S. MacTaggart
  • Patent number: 5456362
    Abstract: A process for the flotation of coarse potash ore fractions in an aqueous brine containing frother that comprises: (a) using a column flotation device in which air bubbles are generated by a sparger that utilizes high intensity shearing to mix and disperse air into brine containing frother; (b) removing a portion of the suspension at another point in the direction of flow of the suspension to regulate the upward flow rate of the suspension past the point where the air is dispersed into the suspension and thereby reducing fine particles entrainment in the froth product. The suspension can be conditioned with an aqueous composition comprising a hydrocarbon extender oil and a substantially saturated long chain primary mine, optionally comprising an acid, such as a mineral acid or carboxylic acid, to emulsify the oil in the composition, or can be conditioned with an aqueous composition comprising a long chain primary amine having an iodine value ranging from about 20 to about 70 cg/g.
    Type: Grant
    Filed: May 26, 1994
    Date of Patent: October 10, 1995
    Assignee: The University of British Columbia
    Inventors: Janusz S. Laskowski, Qun Wang
  • Patent number: 5435443
    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.
    Type: Grant
    Filed: November 3, 1993
    Date of Patent: July 25, 1995
    Inventors: Hermann Hohenester, Helmut Reisser
  • Patent number: 5417806
    Abstract: A method of removing fine contaminants from waste paper fibrous material (S) is described with solution (1) and pre cleaning (2) whereupon the fibrous material is first subjected to a washing treatment (3) and then to a flotation treatment (5). The washing filtrate (12) from the washing treatment (3) is cleaned in a filtrate-flotation treatment (4) so that a cleaned fraction (14) can be returned into the useful material (13) of the washing treatment. The so cleaned waste paper fibrous material can be passed to further treatment steps such as flotation, bleaching and/or dispersion. The reject material from the filtrate-flotation (4) is, in one embodiment, again subjected to a flotation treatment.
    Type: Grant
    Filed: October 19, 1992
    Date of Patent: May 23, 1995
    Assignee: Sulzer-Escher Wyss GmbH
    Inventors: Wolfgang Matzke, Bruno Michelewski
  • Patent number: 5413703
    Abstract: A method and apparatus for dewatering an aqueous coal slurry includes imparting high shear forces to the aqueous coal slurry in the presence of a peptizing agent to render coal particles hydrophobic by stripping clay from the coal particles and peptizing the clay in the aqueous medium of the slurry. The slurry is separating to recover coal particles and the aqueous medium is draining medium from the hydrophobic surface of the coal particles.
    Type: Grant
    Filed: July 22, 1993
    Date of Patent: May 9, 1995
    Inventor: Edward H. Greenwald, Sr.
  • Patent number: 5402893
    Abstract: A method is described for processing waste materials in the form of filter rods, filter cigarettes and the like comprising filter material with inner hollow volumes accessible from the outside and at least one other material component, in particular paper and tobacco, wherein the following process steps are carried out: the waste material is distributed in a liquid in a pressure vessel. By increasing the pressure or decreasing the temperature an inert gas is dissolved in the liquid. Subsequently the temperature is increased or the pressure decreased so that fine gas bubbles develop within the filter material which permits the latter to float whereby a separation from the further material components to be separated is possible. With this method a separation of the waste material into its individual component parts is possible so that for example valuable filter material in the form of cellulose acetate is obtained in highly pure form and can be used again for the production of filter materials.
    Type: Grant
    Filed: July 14, 1993
    Date of Patent: April 4, 1995
    Assignee: Rhone-Poulenc Rhodia Aktiengesellschaft
    Inventor: Karsten Keller
  • Patent number: 5385239
    Abstract: A low brightness pigment and method is provided from a heretofore rejected waste kaolin stream. Kaolin processing rejects are high in iron-stained TiO.sub.2. After separating the stained TiO.sub.2 from the high brightness kaolin and concentrating the resulting fraction, the material can be processed to produce a low brightness pigment suitable of many applications where lower brightness is desirable, such as coating paper board without mottling.
    Type: Grant
    Filed: April 27, 1992
    Date of Patent: January 31, 1995
    Assignee: J. M. Huber Corporation
    Inventors: Albert C. Kunkle, Robert E. Hardy, Bobby R. Skipper
  • Patent number: 5385600
    Abstract: The invention relates to a method for fully beneficating nickel sulfide concentrates or other corresponding mixtures, unsuitable for smelting, by combining the use of both pyrometallurgical and hydrometallurgical processes, so that there are formed two separate concentrates, the first of which is suited to pyrometallurgical and the second to hydrometallurgical treatment. In the concentrate going to pyrometallurgical processing, the valuable metal content increases as a consequence of the treatment, and the Fe/MgO ratio of this concentrate is at least 2.6.
    Type: Grant
    Filed: June 11, 1993
    Date of Patent: January 31, 1995
    Assignee: Outokumpu Harjavalta Metals Oy
    Inventor: Seppo S. Jounela
  • Patent number: 5376276
    Abstract: Aerated bitumen froth containing bitumen, water, air and solids is the product of the hot water extraction process for recovering bitumen from oil sand. Measurements related to the water content of the froth can be obtained by measuring its resonant frequency in a calibrated output, open-ended microwave cavity. By also measuring the bulk density of the froth and assuming a constant relationship for the solids content, one can compute from the assembled data the output quality of the froth. The measurements can be taken repetitively at the vessel as the froth is produced and used to almost instantly provide froth quality information.
    Type: Grant
    Filed: April 1, 1993
    Date of Patent: December 27, 1994
    Assignees: Alberta Energy Company, Ltd., Canadian Occidental Petroleum Ltd., Esso Resources Canada Limited, Gulf Canada Resources Limited, Her Majesty the Queen in right of the Province of Alberta as represented by the Minister of Energy and Natural Resources, Hbog-Oil Sands Limited Partnership, Pancanadian Petroleum Limited, Petro-Canada Inc., Mocal Energy Limited, Murphy Oil Company Ltd.
    Inventors: Keng H. Chung, Gordon R. Thompson, Wayne B. Jansen, Ethel A. Nakano, Samson Y. Ng
  • Patent number: 5368166
    Abstract: The automatic control device comprises a channel used to measure the level and density of pulp in a chamber of a floatation machine, in which two bubbling tubes communicate with a differential pressure transducer connected to the input of a frother flow control channel and to the input of a correction unit whose other input is connected to a pressure transducer communicating with one of the bubbling tubes. The bubbling tubes are installed in hydrostatic tubes located outside the chamber and communicating therewith at different levels relative to the pulp level. The output of the correction unit is connected to the input of a circuit designed to control the flow rate of water and frother in a pulp level stabilizing channel and having its output connected to an actuator valve of a pipeline feeding water and frother.
    Type: Grant
    Filed: September 21, 1990
    Date of Patent: November 29, 1994
    Inventors: Fedor A. Chumak, Vladimir N. Cherednik, Mikhail N. Zlobin
  • Patent number: 5341938
    Abstract: A method of separating desired material from undesired material is provided. The method is performed by forming a slurry of material and introducing it into a specially designed flotation reactor chamber. A foam is generated and introduced into the reactor chamber and dispersed into the slurry. A stream of water is provided to separate the undesired portion of the material from the desired portion of the material that has adhered to the bubbles in the foam.
    Type: Grant
    Filed: May 13, 1993
    Date of Patent: August 30, 1994
    Assignee: Servicios Corporativos Frisco, S.A. de C.V.
    Inventors: Ulises M. Valenzuela, Guillermo Moguel
  • Patent number: 5337965
    Abstract: A method and apparatus for recycling asphalt based roofing material which typically comprises a body of asphalt and fiber, with aggregate on and adhered to the asphalt. The asphalt bodies, with aggregate, are subjected to action to separate or disengage the aggregate from the asphalt body without substantially reducing the size of the aggregate. Disengagement is effected by causing asphalt bodies with aggregate to impact on each other. Disengagement may be effected by placing asphalt bodies with aggregate in water to form in a slurry, which is agitated, as by an impeller. The asphalt bodies float to the top of the liquid, which is a non-solvent for asphalt, and are removed and dewatered; the aggregate of undiminished size is separately recovered.
    Type: Grant
    Filed: October 9, 1992
    Date of Patent: August 16, 1994
    Assignee: Finoll Recycling Ltd.
    Inventor: Domenico Chiovitti
  • Patent number: 5338337
    Abstract: The invention relates to a method of ore beneficiation.The process comprises:(1) grinding the ore to produce a first product comprising ground ore and ground gangue,(2) separating the first product into a fraction having particles of a selected size range and a remainder,(3) separating at least a part of the remainder into a ground ore fraction and a ground gangue fraction,(4) combining the particles of selected size range from step (2) with the ground ore fraction of step (3), and(5) autogenously and/or semi-autogenously grinding the combination of step (4).The process is particularly suitable for lead and/or zinc sulphide ores.In step (5) at least 80% of the resulting ore can be ground to a particle size of less than 6 microns.
    Type: Grant
    Filed: October 22, 1992
    Date of Patent: August 16, 1994
    Assignee: Mount Isa Mines Limited
    Inventors: Norman W. Johnson, John P. Andreatidis
  • Patent number: 5332493
    Abstract: A method for beneficiating a kaolin clay which includes quantities of smectite contaminants to reduce the low and high shear viscosities of high solids aqueous slurries of the kaolin. The smectite is converted into a pillared clay by intercalating it with a polymeric cationic hydroxy metal complex wherein the metal is ferromagnetic or diamagnetic. The kaolin and pillared smectite is then subjected as an aqueous slurry to high intensity magnetic separation, to separate the pillared smectite, and the beneficiated kaolin is recovered as product.
    Type: Grant
    Filed: April 28, 1992
    Date of Patent: July 26, 1994
    Assignee: ECC International Inc.
    Inventors: Michael W. Ginn, Gary L. Cobb
  • Patent number: 5332100
    Abstract: A method for the beneficiation of mineral ores by the flotation method whereby a slurry is introduced under pressure into the top of a first column through a downwardly facing nozzle, and air is entrained into the slurry forming a downwardly moving foam bed in the first column. The foam bed passes from the bottom of the first column into a second column where the froth and liquid separate, the froth carrying the values floating upwardly and over a weir and the liquid being drained with the gangue. The liquid/froth interface level in the second column is kept above the bottom of the first column, and the air flow rate into the top of the first column is controlled to keep the first column substantially full of foam.
    Type: Grant
    Filed: October 27, 1992
    Date of Patent: July 26, 1994
    Assignee: The University of New Castle Research Associates Limited of University of New Castle
    Inventor: Graeme J. Jameson
  • Patent number: 5330655
    Abstract: The invention is directed to a method of regulating a flotation system having an inflow quantity of suspension flow dependent on production demands, including a primary flotation stage and a secondary flotation stage where the secondary flotation stage treats the froth of the primary stage, transporting de-aereated froth from the primary flotation stage to a collection vessel which is in fluid communication the secondary flotation stage; recycling suspension flow from the secondary flotation cells of the secondary flotation stage in part to an inlet of the primary flotation stage, and in part to an inlet of the secondary flotation stage, and regulating the level of de-aereated froth in the collection vessel by controlling the amount of suspension flow recycled from said secondary flotation stage to the inlet of the secondary flotation stage.
    Type: Grant
    Filed: July 30, 1993
    Date of Patent: July 19, 1994
    Assignee: J.M. Voith GmbH
    Inventors: Peter Schweiss, Hans-Dieter Dorflinger
  • Patent number: 5311997
    Abstract: Separation of impurities from kaolin clay is accomplished by conditioning a dispersed aqueous pulp of the clay with an anionic flotation collector, followed by centrifugation or hydrocloning to cause the impurities to settle from a dispersed pulp of the clay without an intermediate froth flotation step or a flotation waste froth is centrifuged or hydrocloned to recover valuable kaolin contained in the froth.
    Type: Grant
    Filed: December 9, 1992
    Date of Patent: May 17, 1994
    Assignee: Engelhard Corporation
    Inventors: George E. Gantt, Thomas J. Adkisson, Preston B. Gladin, Randall E. Ussery, Jr.
  • Patent number: 5307937
    Abstract: A high efficiency method for the recovery of relatively coarse constituent utilizing a flotation column is provided. The method broadly includes the steps of (1) establishing and maintaining a net upward flow of water (negative bias) through the upper portion of the flotation column which is maintained below a predetermined critical limit; (2) establishing and maintaining an upwardly moving stream of diffuse air which is introduced at the lower portion of the flotation column and which has a superficial air velocity between about 0.5 and 2.0 cm/sec.; (3) introducing a feed stream comprising a slurry of the ore into the upper portion of the flotation column wherein the mineral particles therein substantially range between about 20 mesh (840 microns) and about 325 mesh (44 microns) in size; (4) establishing and maintaining the percent solids in the flotation column between about 35 and 50%; (5) establishing and maintaining column throughput of the slurry between 1.8 and 4.0 tons/hour/sq. ft.
    Type: Grant
    Filed: February 17, 1993
    Date of Patent: May 3, 1994
    Assignee: North Carolina State University
    Inventor: Joel F. Hutwelker
  • Patent number: 5305888
    Abstract: A floatation separation method is described for separating pieces of fruit or vegetable of the same type, but wherein desirable pieces have a slightly different specific gravity from the undesirable ones, and all have a specific gravity about the same as that of water. The pieces (12, FIG. 3 ) are placed near the surface of a body of water, and a cloud (40) of tiny air bubbles is maintained in the water. As the bubbles float to the surface they encounter the articles and slightly increase their buoyancy. The increase in buoyancy is slight and uniform, so those articles having a density slightly greater than that of the water will remain at the water surface, while those of a slightly greater density cannot be floated by the air bubbles and will sink to the bottom. The cloud of air bubbles is created by allowing air at about atmospheric pressure, to emerge from apertures in a rapidly spinning rotor that open in a direction primarily opposite to the spin direction.
    Type: Grant
    Filed: July 27, 1992
    Date of Patent: April 26, 1994
    Inventors: Donald M. Meylor, Patrick J. Finn
  • Patent number: 5294003
    Abstract: The invention relates to a flotation column including a plurality of controlled recycle chambers intentionally introduced into the column to cause the non-float fraction or gangue to drop down in the main float stream while the desired float fraction travels in the opposite direction by recycling to continually mix the pulp while coursing through the column. Recycle zones are positioned on the periphery of the main passage or flotation zone within chambers located in series along the column. A portion of the slurry is drawn into a recycle zone where it passes downwardly to return to the flotation zone or the main passage through the column to again be swept through the column.
    Type: Grant
    Filed: March 8, 1993
    Date of Patent: March 15, 1994
    Inventor: Clinton A. Hollingsworth
  • Patent number: 5285972
    Abstract: An improved process for the mechanical separation of complex, intergrown ores containing mineral of at least one of lead or zinc comprises a differential flotation process followed by an agglomeration process. The improved separation process is useful for bulk separation of mixed, intergrown minerals or for separation of one mineral from another, e.g., separation of lead-containing mineral from zinc-containing mineral.
    Type: Grant
    Filed: July 28, 1992
    Date of Patent: February 15, 1994
    Assignee: Shell Research Limited
    Inventors: Cornelius W. Notebaart, Hendricus J. J. J. Megens, Irinaeus B. Klymowsky