Processes Patents (Class 209/164)
  • Patent number: 6799682
    Abstract: Methods of increasing the rate of separating hydrophobic and hydrophilic particles by flotation have been developed. They are based on using appropriate reagents to enhance the hydrophobicity of the particles to be floated, so that they can be more readily collected by the air bubbles used in flotation. The hydrophobicity-enhancing reagents include low HLB surfactants, naturally occurring lipids, modified lipids, and hydrophobic polymers. These methods can greatly increase the rate of flotation for the particles that are usually difficult to float, such as ultrafine particles, coarse particles, middlings, and the particles that do not readily float in the water containing large amounts of ions derived from the particles. In addition, new collectos for the flotation of phosphate minerals are disclosed.
    Type: Grant
    Filed: May 16, 2000
    Date of Patent: October 5, 2004
    Inventor: Roe-Hoan Yoon
  • Publication number: 20040154962
    Abstract: Froth flotation processes, useful for beneficiating base metal mineral values from metal sulfide ore, utilize a collector comprising N-butoxycarbonyl-O-butylthionocarbamate.
    Type: Application
    Filed: February 4, 2004
    Publication date: August 12, 2004
    Inventors: Lino G. Magliocco, Alan S. Rothenberg
  • Patent number: 6772885
    Abstract: The invention relates to a rotor used in the flotation mechanism in the concentration of ores. According to the invention, upper part of the rotor chambers under the rotor cover are formed to be downward inclined from the outer edge of the chambers into the core so that they form an angle between 5 to 70 degrees with the horizontal plane. In addition the upper surface of the rotor cover can be inclined upwards raising from around the rotor shaft towards the outer edge at an angle between 5-70 degrees. With the means inside and above the rotor the slurry is directed upwards through the stator of the flotation mechanism. The developed rotor improves the suspension of coarse particles with high specific gravity within a flotation machine. The invention relates also to a method for inverting the material flow disharging from the rotor.
    Type: Grant
    Filed: September 19, 2003
    Date of Patent: August 10, 2004
    Assignee: Outokumpu Oyj
    Inventor: Peter Bourke
  • Publication number: 20040099575
    Abstract: A process of separating a desired constituent from a mixture of particulate matter including the steps of: conditioning a liquid mixture of particulate matter with a frothing agent to create a pulp; aerating the pulp to generate a float fraction of froth supported on the surface of a non-float fraction of pulp; separating a portion of froth from the float fraction; draining the separated froth; washing the separated froth with a liquid to dislodge particles comprising one or more of non-selectively attached, entrained, and entrapped particles; and recovering the washed froth, is disclosed herein. Also disclosed herein are a froth cleaning apparatus and a froth flotation apparatus for separating a desired constituent from a mixture of particulate matter.
    Type: Application
    Filed: November 27, 2002
    Publication date: May 27, 2004
    Inventors: Latif A. Khan, John Lytle, Ken Ho
  • Publication number: 20040082828
    Abstract: A method for decontaminating soil containing inorganic contaminants having a degree of liberation of at least 60%, comprising the steps of removing from a coarse fraction at least a portion of inorganic contaminants in particulate form contained therein with a jig to produce a treated coarse fraction, removing from an intermediate fraction at least a portion of inorganic contaminants in particulate form contained therein with a separator selected from the group consisting of a spiral and a classifier to produce a treated intermediate fraction, removing from a fine fraction at least a portion of inorganic contaminants in particulate form contained therein with a separator selected from the group consisting of a flotation cell and a multi-gravity separator to produce a treated fine fraction, whereby the combined treated coarse, intermediate and fine fractions are impoverished in inorganic contaminants.
    Type: Application
    Filed: May 23, 2003
    Publication date: April 29, 2004
    Inventor: Mario Bergeron
  • Publication number: 20030226788
    Abstract: A method for decontaminating soil containing inorganic contaminants having a degree of liberation of at least 60%, comprising the steps of removing from a coarse fraction at least a portion of inorganic contaminants in particulate form contained therein with a jig to produce a treated coarse fraction, removing from an intermediate fraction at least a portion of inorganic contaminants in particulate form contained therein with a separator selected from the group consisting of a spiral and a classifier to produce a treated intermediate fraction, removing from a fine fraction at least a portion of inorganic contaminants in particulate form contained therein with a separator selected from the group consisting of a flotation cell and a multi-gravity separator to produce a treated fine fraction, whereby the combined treated coarse, intermediate and fine fractions are impoverished in inorganic contaminants.
    Type: Application
    Filed: December 19, 2002
    Publication date: December 11, 2003
    Inventor: Mario Bergeron
  • Patent number: 6612444
    Abstract: An apparatus for recovering a desired fraction of a raw material bearing the desired fraction has a vessel or cell defining a treatment chamber therein, with an inlet into the chamber for introducing a slurry of raw material to be treated into the chamber. An attrition zone is defined in a portion of the chamber proximate the inlet in the flow path of material introduced into the chamber, the particles being caused to impact against each other in the attrition zone to cause attritioning thereof. A floatation zone is defined in a distal portion of the chamber, in flow communication with the attrition zone, in which attritioned particles from the attrition zone can be contacted with gas bubbles to form a froth phase separated from the slurry by a slurry-froth interface such that the desired fraction is either selectively taken up into the froth phase by the gas bubbles or selectively left behind in the slurry. An outlet from the chamber for the froth phase is present.
    Type: Grant
    Filed: March 9, 2001
    Date of Patent: September 2, 2003
    Assignee: General Signal Corporation
    Inventors: Mark Norman Paul Craddock, Michael Roy Kilner, Warren Wentworth Dale
  • Publication number: 20030146134
    Abstract: Methods of increasing the rate of separating hydrophobic and hydrophilic particles by flotation have been developed. They are based on using appropriate reagents to enhance the hydrophobicity of the particles to be floated, so that they can be more readily collected by the air bubbles used in flotation. The hydrophobicity-enhancing reagents include low HLB surfactants, naturally occurring lipids, modified lipids, and hydrophobic polymers. These methods can greatly increase the rate of flotation for the particles that are usually difficult to float, such as ultrafine particles, coarse particles, middlings, and the particles that do not readily float in the water containing large amounts of ions derived from the particles. In addition, new collectos for the flotation of phosphate minerals are disclosed.
    Type: Application
    Filed: August 14, 2002
    Publication date: August 7, 2003
    Inventor: Roe-Hoan Yoon
  • Patent number: 6536596
    Abstract: The invention relates to a flotation cell line, wherein there are installed, in order to treat the flotatable material, several flotation cells so that the flotatable material can be set to flow through the flotation cell line. According to the invention, the flotation cells (, 1, 2, 3, 4, 5; 31, 32, 33, 34, 35) that are arranged successively in the flowing direction (22, 52) of the flotatable material, are at least partly installed in parallel with respect to each other.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: March 25, 2003
    Assignee: Outokumpu Oyj
    Inventors: Timo Niitti, Matti Tarvainen
  • Patent number: 6520340
    Abstract: The invention relates to a method for improving the operation of a flotation cell line, said flotation cell line comprising several flotation cells (1, 2, 3, 4, 5; 11, 12, 13, 14, 15) that are connected by means of liquid stream flow. According to the invention, at least part of the material flotated in the flotation cell line is conducted past the cell (1, 11) that is located first in the flotation cell line, when seen in the flowing direction (7, 16) of the flotatable material.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: February 18, 2003
    Assignee: Outokumpu Oyj
    Inventor: Timo Niitti
  • Patent number: 6475337
    Abstract: A device and process for aerating dispersions, particularly for flotation of pulp suspensions, in a de-inking process. The process includes at least two stages, where each stage has a separate liquid circulating system which sucks in the gas or air and mixes it with the liquid. The device has at least two flotation cells, with each of the cells having a separate injector and a separate circulation system including a pump.
    Type: Grant
    Filed: February 2, 2001
    Date of Patent: November 5, 2002
    Assignee: Andritz AG
    Inventors: Helmuth Gabl, Erwin Hertl, Bernhard Scherzinger
  • Patent number: 6427843
    Abstract: A process for separating minerals of different mineralogical character. A milled slurry or flotation concentrate is subjected to a first conditioning step (20) followed by a first flotation step (30) followed by a second conditioning step (50) followed by a second flotation step (60). One of the conditioning steps is with an oxidising gas, the other of the conditioning steps being with a non-oxidising gas and an oxidisable surface modifying reagent. The process allows separation of mixtures of valuable minerals by tailoring both the first and second conditioning steps and first and second flotation steps to particular mixed mineral ores.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: August 6, 2002
    Assignee: BOC Gases Australia Ltd.
    Inventor: David William Clark
  • Patent number: 6425485
    Abstract: A process is described for separating particles based on differences in mass after the selective attachment of air bubbles to reduce the density of one or more of the components of the feed. A novel feature of this process is aeration of a hindered-bed of solids in a fluidized-bed separator to create particle/bubble agglomerates that can be separated based on the principal of gravity. This approach offers an improvement in process efficiency that cannot be achieved by other processes. Air and water are mixed in a shear device before the aerated fluidized water is introduced to the separation chamber.
    Type: Grant
    Filed: March 25, 1999
    Date of Patent: July 30, 2002
    Assignee: Eriez Magnetics
    Inventors: Michael J. Mankosa, Gerald H. Luttrell
  • Patent number: 6422393
    Abstract: A process for the recovery of minerals from the fine particle size fraction of froth flotation feed (slimes), which is conventionally discarded to waste because slimes interfere with efficient flotation. In the disclosed process, the slimes, which also may be termed fines, are scrubbed to clean the slimes, and are then subjected to conventional froth flotation. The scrubbing is done in the presence of an attrition media, in addition to chemical reagents for cleaning and dispersing fine particles. Thus an inert attrition media, of larger particle size than the slimes, is introduced into a scrubber. The process accordingly recovers a fine fraction of the flotation feed that is normally lost. The recovery process may be incorporated into an existing plant design, or as part of a new plant designed to recover material previously discarded in waste disposal areas.
    Type: Grant
    Filed: April 14, 2000
    Date of Patent: July 23, 2002
    Inventor: Jeffrey Van Jahnke
  • Patent number: 6413366
    Abstract: Process and device for the flotation of contaminates out of an aqueous fibrous suspension using a foam. The process includes creating the foam, introducing the fibrous suspension into the foam, transferring contaminates from the fibrous suspension to the foam, and removing some portion of the fibrous suspension from the foam as an accepted stock. The device includes a liquid containing area, a mechanism for introducing a gas into the liquid containing area, and a mechanism for introducing the fibrous suspension into a foam containing area arranged to be adjacent the liquid containing area.
    Type: Grant
    Filed: September 19, 2000
    Date of Patent: July 2, 2002
    Assignee: Voith Sulzer Papiertechnik Patent GmbH
    Inventor: Martin Kemper
  • Patent number: 6395131
    Abstract: A flotation machine is provided which includes at least one flotation cell having an inner chamber. The fiber suspension is transported into the inner chamber, and a gas is injected into the fiber suspension within the inner chamber at a temperature above 100° C. to decrease the density of the wax within the fiber suspension. The wax is removed from the fiber suspension.
    Type: Grant
    Filed: September 19, 2000
    Date of Patent: May 28, 2002
    Assignee: Voith Sulzer Paper Technology North America, Inc.
    Inventors: Klaus Doelle, Werner Witek, Oliver U. Heise, Bangji Cao
  • Patent number: 6390303
    Abstract: A method for optimising a mineral recovery process. A slurry 10 is fed to a conditioning step 20. The condition slurry 30 is then provided to a flotation circuit 40 to recover a concentrate 50. The remainder of the slurry is then rejected as tail 60 or passed for further processing. The present invention provides apparatus for analysing a sample stream 100 of the slurry. A sample stream 100 is provided to an analysis device 200 which treats the sample with an oxidising gas similar to the oxidative treatment 20. Several parameters are measured before and/or after the oxidative treatment of the slurry. The flotability characteristic of the slurry is then determined as a function of the measured parameter(s). The result is used to optimise mineral recovery. This apparatus can be used intermittently or continuously to provide on-going optimisation of the mineral recovery circuit.
    Type: Grant
    Filed: July 22, 1999
    Date of Patent: May 21, 2002
    Assignee: BOC Gases Austrailia Ltd.
    Inventors: David William Clark, Billy Kim Fung Chan, Rustam H. Sethna, Peter L. Fleming, Jason Simon Tullai
  • Publication number: 20010025693
    Abstract: A device and process for aerating dispersions, particularly for flotation of pulp suspensions, in a de-inking process. The process includes at least two stages, where each stage has a separate liquid circulating system which sucks in the gas or air and mixes it with the liquid. The device has at least two flotation cells, with each of the cells having a separate injector and a separate circulation system including a pump.
    Type: Application
    Filed: February 2, 2001
    Publication date: October 4, 2001
    Inventors: Helmuth Gabl, Erwin Hertl, Bernhard Scherzinger
  • Patent number: 6290811
    Abstract: The present invention relates to a method for recycling of old corrugated container (OCC) using flotation and kneading treatment and more particularly, to a method for recycling of OCC, wherein OCC is treated withflotation and kneading, treatment, and thereby removing fines and ink spot in the waste pulp and improving the strength and drainage property. As a result, it can be recycled similar to the expensive virgin unbleached kraft pulp.
    Type: Grant
    Filed: June 25, 1999
    Date of Patent: September 18, 2001
    Assignee: Korea Research Institute of Chemical Technology
    Inventors: Jeong Yong Ryu, Kyoung Rak Ji, Jong-Ho Shin, Say Kyoun Ow
  • Patent number: 6290066
    Abstract: A method for removing ammonia and ammonia compounds from fly ash and other combustion by-products is provided. The method may be performed with raw or processed fly ash, or it may be performed in conjunction with a wet beneficiation process. The method involves mixing the ammonia-contaminated fly ash with water and then filtering and/or drying the solution to remove the ammonia and water. The method produces fly ash having an ammonia content of less than about 60-80 ppm, which allows the fly ash to be utilized in a number of applications.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: September 18, 2001
    Assignee: Board of Control for Michigan Technological University
    Inventor: Jiann-Yang Hwang
  • Patent number: 6273263
    Abstract: Disclosed herein is a method for the removal of organic and inorganic contaminants from contaminated sediment or soil. The method comprises a first step of removal and disposal of very large debris while the smaller particle flow is directed to a second step of removal of organic contaminants preferably by means of attrition cell, conditioning tank and flotation columns, the remaining particulate flow, free of organic contaminants, is directed to a third step of removal of inorganic contaminants preferably by means of hydrocycloning to separately deal with very small particles of less than 20 microns, both particulate flows are then preferably subjected to column flotation to separate out the inorganic contaminants. Thus, the method of the present invention yields decontaminated soil or sediment and two distinct contaminant concentrates (organic and inorganic, respectively). Both concentrates can be recovered and used for various applications.
    Type: Grant
    Filed: October 19, 1999
    Date of Patent: August 14, 2001
    Assignee: Institut National de la Recherche Scientifique
    Inventors: Mario Bergeron, Denis Blackburn, Hugo St-Laurent, Anne Gosselin
  • Publication number: 20010010294
    Abstract: The process is designed for the flotation of interfering materials from an aqueous fibrous pulp suspension and is in particular used in the processing of printed or used paper that is otherwise contaminated. The separation of gas bubbles of the suspension occurs in a flotation layer that has a maximum thickness of approximately 100 mm. The process also achieves good flotation results in fibrous pulp suspensions that have a fiber pulp content significantly larger than 1 % by weight, for example around 2% by weight. A flotation apparatus is provided for performing the flotation process. The apparatus includes a flotation vessel, an inlet, an outlet, and a skimmer device.
    Type: Application
    Filed: March 19, 2001
    Publication date: August 2, 2001
    Applicant: VOITH SULZER PAPIERTECHNIK PATENT GmbH
    Inventors: Herbert Britz, Axel Gommel, Herbert Holik, Martin Kemper, Almut Kriebel, Wolfgang Mannes, Boris Reinholdt, Klaus Steinbild
  • Patent number: 6251163
    Abstract: The process of the present invention recovers precious metals from refractory carbonaceous precious metal ores by floating a portion of the ground ore, blending the concentrate with an unfloated portion of the ore, autogenously autoclaving the blended material, cooling the oxidized slurry by dilution, leaching the oxidized slurry after dilution in the presence of a thiosulfate lixiviant, and recovering the precious metal by suitable techniques.
    Type: Grant
    Filed: March 4, 1998
    Date of Patent: June 26, 2001
    Assignee: Placer Dome, Inc.
    Inventor: James A. King
  • Patent number: 6248207
    Abstract: Cellulosic fines and cellulosic fibers are separated from a suspension containing the fines, the fibers and hydrophobic materials by screening the suspension to remove the fibers, and then subjecting the resultant filtrate to dispersed air flotation in the presence of calcium and generally a separation aid to form an upper Reject fraction in which the hydrophobic material is concentrated and a lower Accept fraction in which the cellulosic fines are concentrated.
    Type: Grant
    Filed: May 13, 1999
    Date of Patent: June 19, 2001
    Assignees: CIBA Specialty Chemicals Water Treatment Limited, SCA Graphic Research AB
    Inventors: Paul Kenneth Cutts, Matthew James Green, Bo Gunnar Drehmer, Inger Viktoria Eriksson, Hans Olov Johansson
  • Patent number: 6234318
    Abstract: A method for controlling a froth flotation system in a mineral processing operation for recovering metal from a metal source. A rule-based expert system adjusts performance of the froth flotation system.
    Type: Grant
    Filed: May 4, 1999
    Date of Patent: May 22, 2001
    Assignee: Barrick Gold Corporation
    Inventors: Yves Breau, Martin DeMontigny, Eric Levesque, Jacques McMullen, Dany Pelletier, Pierre Pelletier
  • Patent number: 6228212
    Abstract: The invention comprises, in one form thereof, a method of removing wax from recycled cellulosic fiber. The cellulosic fiber is pulped in a pulper to a suspension with a consistency of less than about 10% by weight. The suspension is then screened to remove coarse and fine contaminants. The screened suspension is diluted to a consistency of less than about 3% by weight. The wax is removed from the diluted suspension using a froth flotation device. The suspension is then washed and/or thickened.
    Type: Grant
    Filed: April 19, 1999
    Date of Patent: May 8, 2001
    Assignee: Voith Sultzer Paper Technology North America, Inc.
    Inventors: Oliver U. Heise, Bangij Cao
  • Patent number: 6227374
    Abstract: The process is designed for the flotation of interfering materials from an aqueous fibrous pulp suspension and is in particular used in the processing of printed or used paper that is otherwise contaminated. The separation of gas bubbles of the suspension occurs in a flotation layer that has a maximum thickness of approximately 100 mm. The process also achieves good flotation results in fibrous pulp suspensions that have a fiber pulp content significantly larger than 1% by weight, for example around 2% by weight. A flotation apparatus is provided for performing the flotation process. The apparatus includes a flotation vessel, an inlet, an outlet, and a skimmer device.
    Type: Grant
    Filed: July 15, 1998
    Date of Patent: May 8, 2001
    Assignee: Voith Sulzer Papiertechnik Patent GmbH
    Inventors: Herbert Britz, Axel Gommel, Herbert Holik, Martin Kemper, Almut Kriebel, Wolfgang Mannes, Boris Reinholdt, Klaus Steinbild
  • Patent number: 6197153
    Abstract: The method for de-inking paper pulp produced by the reduction to pulp, with water, of old papers of various qualities according to which a stream of air bubbles (C) is sent through the flow (E2, S2, E3, S3) of pulp at least once, is characterized by the fact that a countercurrent of water (E1) is sent into the stream of de-inking air bubbles after said bubbles have passed through the pulp and become laden with ink particles so that the countercurrent releases the particles (fibers, fines, fillers) borne along by these de-inking bubbles and carries them away.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: March 6, 2001
    Assignee: E & M Lamort
    Inventor: Alain Serres
  • Patent number: 6186335
    Abstract: A improved process for beneficiating kaolin clays to remove discoloring impurities is disclosed. The beneficiation of kaolin clay is improved by fractionating a kaolin clay starting material into a lower brightness first fraction having a majority of the discoloring impurities and a higher brightness second fraction with less impurities. The first fraction is then beneficiated (such as by flotation, selection flocculation, high intensity magnetic separation and/or leaching) to produce a kaolin clay product with improved optical properties. The first and second fractions may be combined to produce a product with improved optical properties.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: February 13, 2001
    Assignee: Thiele Kaolin Company
    Inventors: Lee Ann Arrington-Webb, Robert A. Lowe, Chris B. Maxwell, Prakash B. Malla, Amy C. Semratedu, Cesar I. Basilio
  • Patent number: 6164456
    Abstract: An elutriation apparatus which combines pressurized liquid nozzles (16A) and the low energy air nozzles (20) producing bubbles for flotation and separation of trace materials in a heterogeneous mixture of materials is described. Quantitative separation of trace evidence is achieved by the apparatus by a closed system of mechanical separations using the water and the air to isolate and deposit trace evidence on a fine mesh screen filter (17) submerged in the water (24) in a container (23). The method provides a rapid, quantitative and inexpensive method for detection of the evidence in soil samples.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: December 26, 2000
    Assignee: Board of Trustees operating Michigan State University
    Inventors: Alvin J. M. Smucker, Jay A. Siegel
  • Patent number: 6129212
    Abstract: The flotation process for separating particulate impurities from fibrous suspensions in a flotation tank. Upon or after entry into the flotation tank, the fibrous suspension added to the flotation tank may be mixed with a portion of the suspension already in the flotation tank. The portion of the suspension already in the flotation tank may be drawn into the added suspension. After mixing, the mixed suspensions enter a mixing element. The mixed suspension is expelled into the flotation tank and a circular flow pattern is generated within the flotation tank as a result. A flow speed may be limited at a top end so that an optimal mixing with the gas bubbles required for flotation may occur with a desired energy savings.
    Type: Grant
    Filed: April 15, 1997
    Date of Patent: October 10, 2000
    Assignee: Voith Sulzer Stoffaufbereitung GmbH
    Inventor: Jens Muller
  • Patent number: 6126836
    Abstract: A superb centrifugal flotation cell with a rotating feed, is provided for use in an effective separation process to rapidly recover greater quantities of valuable fine particles. In the process, a slurry of fine particles is injected with air bubbles and moved downwardly through a stationary pipe and a rotating feed line comprising a centrifugal rotating downfeeder. The slurry is centrifugally discharged from the rotating downfeeder into the flotation chamber where the slurry is separated into a waste stream of non-floating gangue material and a particulate-enriched froth comprising air bubbles carrying a substantial amount of the valuable fine particles for further processing.
    Type: Grant
    Filed: April 12, 1999
    Date of Patent: October 3, 2000
    Assignee: Inter-Citic Mineral Technologies, Inc.
    Inventors: Jian Ding, Wan-Tai Yen, Alan R. Pindred
  • Patent number: 6126014
    Abstract: The carbon and mineral components of fly ash are effectively separated by a continuous air agglomeration method, resulting in a substantially carboree mineral stream and a highly concentrated carbon product. The method involves mixing the fly ash comprised of carbon and inorganic mineral matter with a liquid hydrocarbon to form a slurry, contacting the slurry with an aqueous solution, dispersing the hydrocarbon slurry into small droplets within the aqueous solution by mechanical mixing and/or aeration, concentrating the inorganic mineral matter in the aqueous solution, agglomerating the carbon and hydrocarbon in the form of droplets, collecting the droplets, separating the hydrocarbon from the concentrated carbon product, and recycling the hydrocarbon.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: October 3, 2000
    Assignee: The United States of America as represented by the Department of Energy
    Inventors: McMahon L. Gray, Kenneth J. Champagne, Dennis H. Finseth
  • Patent number: 6103128
    Abstract: A mixing device in the form of a centrifugal pump is used to mix gas (typically air) with liquid (typically effluent water, dispersion water, or waste paper pulp suspension, etc.). The pump is provided with a common inlet conduit for both the liquid and the gas so that liquid and gas flow freely and in an arbitrary ratio into the pump, that is there is no controlling or adjusting of the flows. The gas is allowed to either dissolve in the liquid or be mixed as small bubbles with the liquid, and any surplus gas is separated from the mixing device (e.g. by holes in the pump impeller leading to a rear portion of the pump which is attached to a vacuum source, such as a liquid ring pump). The liquid and gas dissolved therein, and small bubbles mixed therein, are discharged from the mixing device at a pressure that is raised from the inlet pressure, due to the action of the impeller, which pressure development enhances the dissolution of gas in the liquid.
    Type: Grant
    Filed: April 27, 1999
    Date of Patent: August 15, 2000
    Assignee: Sulzer Pumpen AG
    Inventors: Arto Koso, Heikki Manninen
  • Patent number: 6092666
    Abstract: A method is provided for reducing the consumption of alkaline pH modifier in a mineral separation circuit which employs sulfoxy radical-containing reagents. The method comprises the addition of a non-oxidizing gas to the mineral separation circuit prior to and/or simultaneously with the addition of the sulfoxy radical-containing reagent. The non-oxidizing gas is added in a quantity sufficient to achieve a chemical environment conducive to the flotation separation of minerals. The inventive process is suitable for a wide range of valuable minerals including sulfidic copper minerals or mixtures of sulfidic and non-sulfidic copper minerals, sulfidic iron minerals (particularly pyrite) and non-sulfidic gangue material. It is particularly suitable for sedimentary copper deposits, copper skarns, porphyry copper/molybdenum/gold deposits and super gene enrichments.
    Type: Grant
    Filed: July 13, 1998
    Date of Patent: July 25, 2000
    Assignee: BOC Gases Australia Limited
    Inventors: David William Clark, Andrew James Haigh Newell
  • Patent number: 6092667
    Abstract: A method of aerating a liquid comprising the steps of providing a column, introducing liquid under pressure into an upper zone of the column in the form of a jet of liquid directed in a path, permitting gas to be entrained by the jet of liquid, obstructing the path of the jet of liquid to form a zone of turbulence in which bubbles are formed in the liquid to create a foam or froth bed in the column, and removing the foam or froth.
    Type: Grant
    Filed: December 9, 1998
    Date of Patent: July 25, 2000
    Assignee: Multotec Process Equipment Limited
    Inventors: Arno Steinmuller, Michael Hugh Moys, Andre Nardus Terblanche
  • Patent number: 6082549
    Abstract: A process and apparatus serves to remove solid matter from an aqueous material suspension produced from printed used paper. As many interfering material particles are collected by floatation as possible in a floatation foam and diverted as a reject. A perforated separating element is located above the fibrous material suspension. Between the separating element and the floatation foam, an intermediate layer is formed. In the intermediate layer the fibers, which have been entrained by gas bubbles are again rinsed and retrieved.
    Type: Grant
    Filed: July 16, 1998
    Date of Patent: July 4, 2000
    Assignee: Voith Sulzer Papiertechnik Patent GmbH
    Inventors: Axel Gommel, Martin Kemper
  • Patent number: 6059118
    Abstract: A user-friendly centrifugal flotation cell with a rotating drum, is provided for use in an efficient separation process to rapidly recover greater quantities of valuable fine particles. In the process, a slurry of fine particles is injected with air bubbles and moved downwardly through a stationary downfeeder to a centrifuge comprising a rotating flotation cell. The aerated slurry is centrifugally separated into a waste stream of non-floating gangue material and a particulate-enriched froth comprising air bubbles carrying a substantial amount of the valuable fine particles. The froth is processed by froth flotation in a froth flotation chamber.
    Type: Grant
    Filed: April 12, 1999
    Date of Patent: May 9, 2000
    Assignee: Inter-Citic Mineral Technologies, Inc.
    Inventors: Jian Ding, Wan-Tai Yen, Alan R. Pindred
  • Patent number: 6056125
    Abstract: An apparatus and process for the separation of coal from pyritic impurities using a modified froth flotation system. The froth flotation column incorporates a helical track about the inner wall of the column in a region intermediate between the top and base of the column. A standard impeller located about the central axis of the column is used to generate a centrifugal force thereby increasing the separation efficiency of coal from the pyritic particles and hydrophillic tailings.
    Type: Grant
    Filed: July 8, 1997
    Date of Patent: May 2, 2000
    Assignee: U. S. Department of Energy
    Inventors: Ralph W. Lai, Robert A. Patton
  • Patent number: 6044978
    Abstract: The present invention provides a process for the recovery of base metal sulfides including chalcocite, chalcopyrite, pentlandite and platinum group metal bearing mineral ores. The process involves passing a slurry of the ore through a reagent conditioning stage wherein suitable activators, collectors, frothers and/or depressants are added, further conditioning the slurry with a non-oxidizing gas in a quantity conducive to the separation of the sulfide minerals from the remainder of the ore and subsequently subjecting the slurry to a final flotation treatment with a flotation gas having a higher oxygen content than the non-oxidizing gas. The non-oxidizing gas conditioning can be carried out prior to or after the reagent conditioning stage.
    Type: Grant
    Filed: July 13, 1998
    Date of Patent: April 4, 2000
    Assignee: BOC Gases Australia Limited
    Inventors: Andrew James Haigh Newell, David William Clark, Henry Nhlanhla Gumede
  • Patent number: 6041941
    Abstract: A method for reducing both reagent consumption and scale formation in a mineral separation circuit employing sulfoxy compounds as reagents. The method involves introducing into the mineral separation circuit a non-oxidizing gas in a quantity sufficient to reduce the degree of oxidation of the sulfoxy radical. Preferably the gas is introduced during the reagent conditioning and flotation stages, the stages where the presence of dissolved oxygen in a slurry is most likely to create the conditions conducive to oxidation of the sulfoxy radicals which result in reagent consumption and scale formation problems. The process is suitable for a wide range of mineral separation circuits which use sulfoxy reagents for the separation of sulfidic minerals including chalcopyrite, pentlandite, pyrite, sphalerite, pyrrhotite or galena.
    Type: Grant
    Filed: June 24, 1998
    Date of Patent: March 28, 2000
    Assignee: BOC Gases Australia Limited
    Inventors: Andrew Newell, Walter Hoecker
  • Patent number: 6036025
    Abstract: A process for the separation of minerals of different mineralogical character. The process involves conditioning a milled slurry or a slurry of a flotation concentrate which contains a mixture of valuable sulfidic minerals and non-sulfidic gangue material with an inert/non-oxidizing gas and/or a reducing/deoxifying agent. The conditioning is conducted to achieve a controlled dissolved oxygen content or electrochemical reduction potential conducive to the separation of the valuable sulfidic mineral, non-sulfidic gangue material. The inert/non-oxidizing gas and/or reducing/deoxifying agent may be added to the slurry in a quantity sufficient to increase rejection of the non-sulfidic gangue minerals or to improve the selectivity between the valuable sulfidic minerals and non-sulfidic gangue minerals.
    Type: Grant
    Filed: March 26, 1998
    Date of Patent: March 14, 2000
    Assignee: BOC Gases Australia Limited
    Inventors: David W. Clark, Andrew J. Newell
  • Patent number: 6032805
    Abstract: A method of increasing both flotation selectivity and effectiveness of a sulfoxy radical-containing reagent added to a mineral separation circuit. The method involves adding a non-oxidizing gas to the mineral separation circuit prior to and/or simultaneously with the addition of the sulfoxy radical-containing reagent in a quantity sufficient to achieve a chemical environment conducive to flotation separation of minerals. The process is suitable for use with a broad range of slurries and flotation concentrates having a mixture of valuable materials including sulfidic copper minerals, sulfidic and non-sulfidic copper minerals, valuable lead and/or zinc and/or nickel minerals, sulfidic iron minerals (particularly pyrite) and non-sulfidic gangue material. It is particularly suitable for polymetallic ores containing economic values of copper and/or lead and/or zinc and/or nickel which is frequently in association with iron sulfide.
    Type: Grant
    Filed: July 13, 1998
    Date of Patent: March 7, 2000
    Assignee: BOC Gases Australia Limited
    Inventors: David William Clark, Andrew James Haigh Newell
  • Patent number: 6007618
    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: November 10, 1997
    Date of Patent: December 28, 1999
    Assignee: Thiele Kaolin Company
    Inventors: Joseph Allen Norris, Jorge L. Yordan
  • Patent number: 6000551
    Abstract: A method for rupturing microalgae in an aqueous suspension is disclosed. In one embodiment the aqueous suspension is passed through a constriction into a liquid phase at a pressure sufficient to rupture the cells by circulating the aqueous suspension through a constriction in a pump loop at a pressure and a percent recycle sufficient to rupture the cells. Cells of the alga Dunaliella salina can be ruptured by the method of the invention to promote froth flotation and mechanical filtration of the cells for recovery of mixed carotenoids.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: December 14, 1999
    Assignee: Eastman Chemical Company
    Inventors: Jeffrey Scott Kanel, Scott Arthur Guelcher
  • Patent number: 6000552
    Abstract: A process for the purification of a fiber suspension (deinking or white water) in which a mixture of fiber suspension and gas bubbles are jtted into a flotation tank in an upwardly directed manner toward the free surface of the pulp at a velocity of greater than Sm/s and the jet ends at or just below the free surface of the mixture.
    Type: Grant
    Filed: May 6, 1999
    Date of Patent: December 14, 1999
    Assignee: Sunds Defibrator Industries AB
    Inventors: Thomas Eriksson, Borje Fredriksson, Tomas Wikstrom
  • Patent number: 5988396
    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: August 18, 1998
    Date of Patent: November 23, 1999
    Assignee: ISG Resources, Inc.
    Inventors: Rafic Y. Minkara, Jerry L. Heavilon
  • Patent number: 5936216
    Abstract: A froth floatation process for separating carbon from coal ash incorporates a step of screening the coal ash before the coal ash is formed into a slurry.
    Type: Grant
    Filed: December 1, 1998
    Date of Patent: August 10, 1999
    Inventor: Chiung-Hsin Wu
  • Patent number: 5925862
    Abstract: A process for the production of cobalt concentrate from an ore containing metal sulfides including sulfides of lead, zinc, and cobalt. The ore is crushed and subjected to a lead and cobalt flotation to separate the lead and cobalt from the zinc and produce a bulk lead cobalt concentrate. The lead cobalt concentrate is then subjected to a cobalt flotation to separate the cobalt from the lead and produce a cobalt concentrate.
    Type: Grant
    Filed: November 21, 1997
    Date of Patent: July 20, 1999
    Assignee: The Doe Run Company
    Inventors: John C. Morrisey, IV, Quentin J. Schmidt
  • Patent number: 5917166
    Abstract: Methods for washing sawdust are disclosed which include providing a mixture of sawdust and water to a vessel, subjecting the mixture to a reduced pressure so that gases present in the sawdust cause expansion therein and the sawdust rises to the surface of the mixture while the contaminants descend within the vessel, and withdrawing the sawdust from the vessel, in which the sawdust is withdrawn from the vessel at a location above the point where the sawdust and water enter the vessel. Apparatus for carrying out this method is also disclosed.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: June 29, 1999
    Assignee: Sunds Defibrator Industries AB
    Inventor: Jan Henriksson