Deflocculation And Flocculation Patents (Class 209/5)
  • Patent number: 5019245
    Abstract: A method is provided for separating an inert solid substantially inorganic fraction comprising sand or soil from a tarry or oily organic matter in a feedstock. The feedstock may be contaminated soil or tarry waste. The feedstock is combined with pulverized coal and water. The ratio (oil or tar to dry weight of coal) of about 1.0:10 to about 4.0:10 at a temperature in the range of 60.degree.-95.degree. C. The mixture is agitated, the coarse particles are removed, and up to about 0.10% by weight (based on weight of coal) of a frothing agent is added. The mixture is then subjected to flotation, and the froth is removed from the mixture.
    Type: Grant
    Filed: June 2, 1989
    Date of Patent: May 28, 1991
    Inventors: Teresa Ignasiak, Ali A. Turak, Wanda Pawlak, Boleslaw L. Ignasiak, Carlos R. Guerra, Melvin L. Zwillenberg
  • Patent number: 5008089
    Abstract: Red mud in Bayer process liquors are flocculated using dextran and synthetic anionic polymer in the same stage, usually added separately to the liquor. The liquor may be the primary settler slurry, the secondary clarification liquor or one or more of the red mud washing stages. The process is of particular advantage where the liquors are high in carbonate content and/or total alkalinity.
    Type: Grant
    Filed: October 13, 1989
    Date of Patent: April 16, 1991
    Assignee: Allied Colloids Limited
    Inventors: Gillian M. Moody, Christine A. Rushforth
  • Patent number: 5006231
    Abstract: A control system having opto-electric detectors responsive to different solids concentrations and character of the solids of a slurry, the output of the detectors controlling the addition of a flocculants to the slurry to optimize coagulation of the materials in the slurry. The detectors having outputs sensing different slurry conditions with the detector outputs being processed to control the addition of different flocculants to the cell.
    Type: Grant
    Filed: August 24, 1990
    Date of Patent: April 9, 1991
    Assignee: Consolidation Coal Company
    Inventors: Hayward B. Oblad, Gary F. Meenan
  • Patent number: 4998624
    Abstract: Carbonaceous components are separated from particulate coal containing inorganic solids by agitating and aerating the coal, agglomerating oil and water to form agglomerates of carbonaceous components of the coal and oil with air trapped in the agglomerates. The air trapped in the agglomerates makes them buoyant so that they collect at the surface of the water, for easy removal, while inorganic residual solids collect at the bottom of the water. The inorganic solids containing coal comprise previously formed agglomerates which are broken down by the agitation to form a slurry. In the latter case the process is for removal of inorganic solids which were not removed during the initial agglomeration. The agitation may be accomplished by a stirrer, impeller or a pump.
    Type: Grant
    Filed: November 16, 1989
    Date of Patent: March 12, 1991
    Assignee: Canadian Patents and Development Limited
    Inventors: C. Edward Capes, Richard D. Coleman, Joseph L. S. Croteau, William L. Thayer
  • Patent number: 4990262
    Abstract: Aqueous mineral slurries are treated prior to dewatering, to increase throughput, with a condensation product of formaldehyde and dicyandiamide, which may be further reacted with ammonia or an ammonia salt and an alkylenepolyamine or copper chloride.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: February 5, 1991
    Inventor: Andrew J. Sharpe, Jr.
  • Patent number: 4990263
    Abstract: Finely divided aqueous mineral slurries such as kaolin clay and calcium carbonate are dewatered, filtered and prepared for shipment by and with the addition of an effective amount (preferably 0.01 to 4.0 pounds per ton of solids) of melamine/formaldehyde polymer.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: February 5, 1991
    Inventor: Andrew J. Sharpe, Jr.
  • Patent number: 4990264
    Abstract: The present invention is directed to a dewatering aid which functions unexpectedly efficiently in the dewatering of a particulate solids slurry, e.g. mineral ore concentrate or slurry, wherein a dewatering aid is added thereto followed by filtration of the slurry. Such improved dewatering results are achieved by adding to the mineral ore slurry, an effective amount of a dewatering aid comprising an alkoxylated C.sub.6 -C.sub.11 alkanol or alkanoic acid wherein alkoxylation is conducted with propylene oxide or butylene oxide.
    Type: Grant
    Filed: October 13, 1989
    Date of Patent: February 5, 1991
    Assignee: Sherex Chemical Company, Inc.
    Inventors: James G. Fuller, Owen Portwood, Joe W. Cotton
  • Patent number: 4976781
    Abstract: Noble metal or diamond values are recovered from ore slurries by contact with pellets of oil, coal and bitumen as a secondary binder. The pellets are of a size above 0.75 mm and contain 2% bitumen and 18% lighter oil fractions. The pellets do not disintegrate and size range remains constant.
    Type: Grant
    Filed: August 21, 1987
    Date of Patent: December 11, 1990
    Assignee: Charlton Mineral Associates Pty. Ltd.
    Inventors: David Mainwaring, Mark Cadzow
  • Patent number: 4972956
    Abstract: Carbonaceous coal particles, essentially free of pyritic sulphur, are removed from an aqueous coal slurry in two steps. In the first step the carbonaceous particles of the slurry, with the pyritic sulphur essentially free of surface conditioning agent, are micro-agglomerated with agglomerating oil added in an amount varying from about 0.5 wt % (dry basis), when the coal particle average size is about 100 microns, to about 10 wt % (dry basis) when the average coal particle size is about 4 microns to remove relatively coarser particles of pyritic sulphur. Then, without adding any further agglomerating oil, relatively finer pyritic sulphur particles trapped with water in the micro-agglomerates are removed.
    Type: Grant
    Filed: March 21, 1989
    Date of Patent: November 27, 1990
    Assignee: National Research Council of Canada
    Inventors: Richard D. Coleman, Serge Croteau, Charles E. Capes
  • Patent number: 4956077
    Abstract: Particles of a desired mineral are recovered from particles of an unwanted mineral in an aqueous slurry by a froth flotation process in which, after treatment of the mineral particles with a collector, a predominantly hydrophobic polymeric flocculating agent, which will selectively flocculate the desired mineral particles, is added to the slurry. The predominantly hydrophobic polymeric flocculating agent may be for example a polyvinyl ether or a polybutadiene and may be predispersed in a carrier liquid, which may be the frother used to produce the froth.
    Type: Grant
    Filed: October 21, 1988
    Date of Patent: September 11, 1990
    Assignee: Fospur Limited
    Inventor: Christopher H. Barwise
  • Patent number: 4931190
    Abstract: An improved method for dewatering thin slurries of very fine clay or clay-like material to yield high solids content filter cake, for example, 40% solids and greater, by the use of flocculating agent combinations involving polyethylene oxide-type flocculating agents and polyacarylamide-type flocculating agents. The method generally involves admixing the combination of flocculating agents with the slurry, dewatering the slurry by means of a mechanical dewatering apparatus and feeding the thickened slurry to a belt press filter.
    Type: Grant
    Filed: December 27, 1988
    Date of Patent: June 5, 1990
    Assignee: Envirotech Corporation
    Inventor: Timothy J. Laros
  • Patent number: 4911848
    Abstract: A method of spreading a pulp for the purpose of drying it naturally, the pulp having a solid fraction which has a d.sub.80 of less than 100 microns. This method comprises the following steps:(a) adjusting the level of solids of the pulp to between 2 and 25%;(b) adding a flocculating agent to the pulp and mixing it with same, the amount of said flocculating agent being between two-thirds of 98% of the optimum required fo the flocculation of said pulp; and(c) spreading the mixture of pulp and flocculating agent, in the open air, in a bed the sides of which are permeable, and the bottom of which has a slope of less than 5 meters per 1000 meters, said spreading taking place 1 to 20 minutes after the adding are mixing of the flocculating agent.
    Type: Grant
    Filed: March 1, 1988
    Date of Patent: March 27, 1990
    Assignee: Eramet-SLN (formerly Societe Metallurgique le Nickel-SLN
    Inventors: Jean-Louis Cardini, Jean-Pierre Fer, Claude Laurent
  • Patent number: 4909946
    Abstract: Water can be removed from an aqueous clay slurry using techniques such as filtration wherein the slurry is contacted with an anionic polymer having a molecular weight in the range from about 3,000 to about 1,000,000. The water is removed from the slurry at a rapid rate in order to provide a clay cake.
    Type: Grant
    Filed: December 5, 1986
    Date of Patent: March 20, 1990
    Assignee: The Dow Chemical Company
    Inventor: James W. Sanner
  • Patent number: 4906386
    Abstract: Coal fines are flocculated from an aqueous suspension by adding an anionic polyelectrolyte, a soluble calcium salt, and a cationic polyelectrolyte to the suspension. The anionic polyelectrolyte is preferably a high charge density, high molecular weight acrylic acid/acrylamide copolymer or a high charge density high molecular weight terpolymer of acrylic acid/methacrylic acid/ethylacrylate. The cationic polyelectrolyte is preferably a high molecular weight, low charge density dimethylamino methylmethacrylate methyl chloride quaternary ammonium salt/acrylamide copolymer, an N,N dimethyl 2 hydroxy propyl imine homopolymer or low molecular weight, a diallyl dimethyl ammonium chloride polymer, or ter polyepichlorohydrin dimethyl amine.
    Type: Grant
    Filed: November 3, 1988
    Date of Patent: March 6, 1990
    Assignee: Betz Laboraties, Inc.
    Inventors: Stephen R. Vasconcellos, Phuong-Thao Luong
  • Patent number: 4904373
    Abstract: disclosed is a process for separating resin from a mixture of resin-bearing coal particles by increasing the pH of a froth flotation process to a value of at least 12. Particles of reduced size resin-bearing coal are preferably mixed with water to from a slurry. The pH of the slurry is then adjusted with a chemical agent to about 12. The slurry is then subjected to froth flotation. The coal particles aggregate to one another allowing the remaining resin-rich particles to attach to the bubbles formed during the flotation process. A much improved separation efficiency for resin flotation from coal is observed.
    Type: Grant
    Filed: April 4, 1989
    Date of Patent: February 27, 1990
    Assignee: University of Utah
    Inventors: Jan D. Miller, Qiang Yu, Ye Yi
  • Patent number: 4892663
    Abstract: Disclosed is a method for dewatering an aqueous slurry of solid coal particulates wherein a dewatering aid is added to the slurry followed by filtration thereof, preferably with vacuum augmentation. Selected quaternary ammonium dewatering aids of specific structure are disclosed.
    Type: Grant
    Filed: December 2, 1988
    Date of Patent: January 9, 1990
    Assignee: Sherex Chemical Company, Inc.
    Inventor: Robert O. Keys
  • Patent number: 4887722
    Abstract: A method for beneficiating a coal refuse feed stream which includes agglomerated carbonaceous and clay particles. The feed stream is rapidly heated to volatilize moisture. Heating is carried out in a manner to produce abrasive commutation and sub-divide particles by volatilizing the moisture. After deagglomerating the feed stream, the discreet particles essentially consisting of carbonaceous particles and clay particles are separated to form a plurality of differently sized classifications of granular particles. A carbonaceous particle fraction essentially comprised of granular particles having a particle size greater than about 2 microns is recovered to form one fraction and a minus 2 micron fraction is classified to separate particles from the component gas. In one embodiment, a dust laden gas fraction is treated in an air classifier to form a coarse particle fraction and a fine particle fraction. The recovered coarse particle fraction can be used as a carbonaceous fuel.
    Type: Grant
    Filed: December 11, 1987
    Date of Patent: December 19, 1989
    Inventor: Edward H. Greenward, Sr.
  • Patent number: 4867867
    Abstract: This invention relates to a method of enhanced recovery of phosphate in the double flotation process for the benefication of phosphate ore, more particularly to the use of pH modifiers-silica depressants:sodium silicate;soda ash (Na.sub.2 CO.sub.3); orsoda silicate and soda ash, alone or in combination with one or more ingredients selected from the group consisting of: starch, dextrin, sodium sulfite and trisodium phosphate, added to the casutic or ammonia reagent used to prepare the patty acid-fuel oil mixture in the first stage of the double flotation process.
    Type: Grant
    Filed: April 5, 1984
    Date of Patent: September 19, 1989
    Assignee: J. Warren Allen
    Inventor: Geroge M. Lilley
  • Patent number: 4859318
    Abstract: Coal fines are recovered from an aqueous slurry which also contains shale as suspended fine solids by adding to the slurry a hydrophobic polymer such as a polybutadiene or a polyvinylether in a liquid organic carrier such as gas oil, diesel oil or kerosene, agitating the resulting mixture, introducing gas such as air into the mixture to form bubbles whereby flocs of coal fines formed are caused to float, and discarding the underlying slurry containing shale. To aid solution of the polymer a co-solvent, such as an aromatic solvent or a paraffinic solvent, compatible with the carrier may be used. The method is preferably carried out as a froth flotation in a froth flotation cell using a conventional frother such as methyl isobutyl carbinol or a mixture of polypropylene glycol ethers in addition to the polymer and carrier.
    Type: Grant
    Filed: October 16, 1987
    Date of Patent: August 22, 1989
    Assignee: Fospur Limited
    Inventors: Gerald F. Brookes, Lynne Spencer
  • Patent number: 4857221
    Abstract: Coal fines are recovered from an aqueous slurry which also contains shale as suspended fine solids by adding to the slurry a hydrophobic polymer such as a polybutadiene or a polyvinylether in a liquid organic carrier such as gas oil, diesel oil or kerosene, agitating the resulting mixture, introducing gas such as air into the mixture to form bubbles whereby flocs of coal fines formed are caused to float, and discarding the underlying slurry containing shale. To aid solution of the polymer a co-solvent, such as an aromatic solvent or a paraffinic solvent, compatible with the carrier may be used. The method is preferably carried out as a froth flotation in a froth flotation cell using a conventional frother such as methyl isobutyl carbinol or a mixture of polypropylene glycol ethers in addition to the polymer and carrier.
    Type: Grant
    Filed: August 12, 1988
    Date of Patent: August 15, 1989
    Assignee: Fospur Limited
    Inventors: Gerald F. Brookes, Lynne Spencer
  • Patent number: 4853133
    Abstract: The water content of wet small coal is reduced by adding a defined amount of an ionic surfactant, centrifuging, and adding a foam suppressing amount of a cationic organic compound to the aqueous effluent from the centrifugation step.
    Type: Grant
    Filed: December 10, 1987
    Date of Patent: August 1, 1989
    Assignee: The British Petroleum Company p.l.c.
    Inventors: Steven A. Flynn, Paul R. Rutter
  • Patent number: 4830634
    Abstract: A process is taught for preparing a coal substitute of low ash level from a composite of coal, mineral matter and pyritic sulfur comprising comminuting the coal composite in an aqueous medium to a size range which promotes the liberation of the mineral matter; subjecting the resulting slurry to fines agglomeration in the presence of a water-insoluble bridging organic liquid; separating the agglomerates from the liquid phase containing the bulk of the mineral matter and a portion of the pyritic sulfur; treating the coal fines by stripping the organic liquid from the fines surface; and redispersing the fines in an aqueous medium having a surface active agent to yield a high solids coal fines slurry so to permit magnetic separation of residual pyritic sulfur and other magnetic mineral matter.
    Type: Grant
    Filed: September 3, 1986
    Date of Patent: May 16, 1989
    Assignee: Exportech Company, Inc.
    Inventor: Robin R. Oder
  • Patent number: 4781298
    Abstract: A process for the wet processing of kaolin clay which includes a step for physically removing discrete particles of colored impurities by high gradient magnetic separation (HGMS) in which all processing steps including HGMS are carried out with the feed clay slurry at high solids, above 50%, and the magnetically purified clay slurry is also recovered at high solids, above 50%. A feature of the invention is that the HGMS unit is operated in a novel manner such as to avoid the dilution of the magnetically purified clay slurry with water during all stages of HGMS treatment without adverse effect on the yield of magnetically purified clay.
    Type: Grant
    Filed: December 3, 1986
    Date of Patent: November 1, 1988
    Assignee: Engelhard Corporation
    Inventors: Glen A. Hemstock, Mitchell J. Willis
  • Patent number: 4781671
    Abstract: Commercial wide size distribution powders are size classified into precise size fractions by means of a controlled, semi-continuous, multi-stage centrifugal classification system. The system has utility for a wide range of colloidal materials. The throughput of the semi-continuous process is higher than that of batch processes, and the semi-continuous process produces narrow size ranges and optimum yields.
    Type: Grant
    Filed: March 28, 1987
    Date of Patent: November 1, 1988
    Assignee: Ceramics Process Systems Corporation
    Inventors: Richard L. Pober, Bruce E. Novich
  • Patent number: 4778598
    Abstract: A process for separating ash particles from an aqueous slurry containing a mixture of regenerated adsorbent (e.g., carbon) and ash particles includes the steps of settling the slurry to produce a solid phase including the mixture of adsorbent and ash particles and a supernatant or a clarified aqueous phase. After separation of the aqueous phase, a slurry of the solid phase is diluted with water and a dispersing agent for promoting suspension of the ash particles and an anionic polymer for promoting settling of the adsorbent particles are added. The thus-treated, dilute slurry is settled to produce an aqueous phase containing primarily suspended ash particles and a solid phase including carbon particles. After separation, the solid phase can be returned to a wastewater treatment system.
    Type: Grant
    Filed: February 2, 1987
    Date of Patent: October 18, 1988
    Assignee: Zimpro Inc.
    Inventors: Mark C. Hoffman, Marvin J. Dietrich, Thomas P. Oettinger
  • Patent number: 4770766
    Abstract: Methods of recovering agglomerated particles of a carbonaceous constituent such as coal from a composite of that constituent and mineral matter. An additive is incorporated into a slurry of the composite to control the agglomeration time and/or to insure that the carbonaceous particles will agglomerate. Appropriate additives are:Naturally occurring hydrocarbonaceous substances such as road asphalts, Gilsonite, pentane extracts of coals, tar sands oils, coal tars, and alcohols having six or more carbon atomsCastor oilIsopropyl etherHydrolized linseed oil2-Ethylhexyl acetateIonic dispersants such as ammonium salts of lignosulfonatesNonionic dispersants such as dextrinsA compound having the formula R--O--R, R.sub.2 --CO, R--COOH, or R--COOR where R is an aliphatic moiety having at least six carbon atoms.
    Type: Grant
    Filed: March 12, 1986
    Date of Patent: September 13, 1988
    Assignee: Otisca Industries, Ltd.
    Inventors: Douglas V. Keller, Jr., William M. Burry
  • Patent number: 4767540
    Abstract: The suspended solids content of Bayer process streams is reduced by contacting said stream with a polymer which contains hydroxamic acid groups.
    Type: Grant
    Filed: February 11, 1987
    Date of Patent: August 30, 1988
    Assignee: American Cyanamid Company
    Inventors: Donald P. Spitzer, Wei S. Yen
  • Patent number: 4758332
    Abstract: In a method of agglomerating carbonaceous coal comprising first agglomerating impurity liberated carbonaceous coal, from an impurity liberated coal slurry, with agglomerating oil to form open structured, chain-like, micro-agglomerates and then forming relatively larger, less open structured more robust agglomerates from a portion of the slurry to provide a mixture of micro-agglomerates, relatively larger, more robust agglomerates, water and any inorganic impurities that may be present. The relatively larger, more robust agglomerates are screened and then the micro-agglomerates are separated using an aerating, skimmer tank leaving an inorganic impurity laden waste water. The micro-agglomerates are rendered buoyant by the aeration and are thus rendered separable from the inorganic laden waste water which may be further treated to remove the inorganic waste to provide water for recirculation.
    Type: Grant
    Filed: August 10, 1987
    Date of Patent: July 19, 1988
    Assignee: National Research Council of Canada
    Inventors: Charles E. Capes, Kevin A. Jonasson, William L. Thayer
  • Patent number: 4756823
    Abstract: The present invention provides a blended preparation for the separation especially of coal particles from the tailings which are contained in the fines produced in coal mining. The blended preparation is used instead of or in addition to the conventional froth oil. The blended preparation comprises froth oil, flocculating agent, emulsifying agent, water and optionally, anti-freeze. The use of the preparation results in faster separation and saving in flocculating agent.
    Type: Grant
    Filed: March 5, 1986
    Date of Patent: July 12, 1988
    Assignee: Carbo Fleet Chemical Co., Ltd.
    Inventors: Derek O'Neill, James A. Robson, Leonard K. Pugh
  • Patent number: 4750992
    Abstract: Classification of alumina particulate is achieved through use of a basic aluminum compound as a dispersant.
    Type: Grant
    Filed: April 9, 1986
    Date of Patent: June 14, 1988
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: James C. Romine
  • Patent number: 4749492
    Abstract: Regenerated adsorbent particles, such as activated carbon, are recovered from a wet oxidation-regenerated mixed liquor sludge from a wastewater treatment system by diluting and settling a blowdown slurry from the wet oxidation reactor to obtain a first aqueous phase containing primarily regenerated adsorbent particles and fine ash particles and a first solids phase containing primarily grit particles. The first aqueous phase is combined with a portion of the regenerated adsorbent particle slurry withdrawn from the upper portion of the wet oxidation reactor and, after treatment with a dispersing agent and then an anionic flocculating agent, the resulting mixture is settled to obtain a second aqueous phase containing primarily fine ash particles and a second solids phase containing primarily regenerated adsorbent particles.
    Type: Grant
    Filed: July 6, 1987
    Date of Patent: June 7, 1988
    Assignee: Zimpro/Passavant
    Inventors: John K. Berrigan, Jr., David A. Beula, William M. Copa
  • Patent number: 4741837
    Abstract: For the purpose of increasing the efficiency during drying of brown coals having a high water content and for the purpose of facilitating the purification of process waste water resulting in a drying process according to Fleissner it is proposed to spray hot water onto the raw coal and to separate the proportion in fine grain having a maximum grain size of 5 mm, preferably of 1 mm. In the following, the proportion in fine grain is subjected to an adsorption stage (5), noting that after a reaction time of at least 1 min, preferably of 2 to 5 min, a major portion of the soluble substances burdening the waste water becomes adsorbed on this fine grain. Subsequently, the waste water is further purified after a flocculating step in a flocculating reactor (6) and after a separating step (8) for separating solid matter, for which purpose can be used sand filters (10), adsorbing resins and activated carbon.
    Type: Grant
    Filed: November 5, 1986
    Date of Patent: May 3, 1988
    Assignee: Voest-Alpine Aktiengesellschaft
    Inventors: Michael Schweizer, Jaroslav Fohl, Gero Tessmer
  • Patent number: 4741838
    Abstract: Aqueous mineral slurries containing 10% by weight or more of finely divided mineral solids are flocculated prior to dewatering and/or thickening to obtain improved throughput and/or to reduce moisture in the dewatered product, by treating the slurries with polymers comprising at least about 1% by weight 2-acrylamido-2-methyl propyl sulfonic acid copolymerized with acrylamide and/or other suitable water-soluble monomers. The polymers must have a Brookfield viscosity of at least 7000 cps at 7.5% concentration in water. Flocculation of the mineral slurries with these polymers also provides improved re-dispersibility of the dewatered mineral in the filter cake. During redispersion, additional dry mineral may be added to obtain a final solids content as high as 70% or more. The Brookfield viscosity of the final high solids slurry comprising a significant portion of filter cake treated with the flocculants of this invention is not detrimentally affected.
    Type: Grant
    Filed: June 11, 1986
    Date of Patent: May 3, 1988
    Inventor: Andrew J. Sharpe, Jr.
  • Patent number: 4738726
    Abstract: A highly bulked kaolin pigment is prepared by mixing a small but effective amount of a water-soluble cationic polyelectrolyte flocculant with a kaolin clay pigment in the presence of water to prepare a bulked clay pigment product. Upon dewatering, the resultant polyelectrolyte treated clay product can be dispersed to form high solids clay-water slurries useful in making aqueous coating colors suitable for manufacturing coating lightweight publication papers or the pigment can be used as a filler for paper webs.
    Type: Grant
    Filed: May 12, 1986
    Date of Patent: April 19, 1988
    Assignee: Engelhard Corporation
    Inventors: Richard J. Pratt, Richard A. Slepetys, Saad Nemeh, Mitchell J. Willis
  • Patent number: 4735707
    Abstract: Mineral particles are separated from solid carbonaceous fuel by using magnetic separation. A mixture of mineral particles, carbonaceous fuel, ferromagnetic particles and polyacrylamide in water is subjected to magnetic separation to remove a magnetized fraction enriched in mineral water.
    Type: Grant
    Filed: May 27, 1986
    Date of Patent: April 5, 1988
    Assignee: The British Petroleum Company p.l.c.
    Inventor: Heriberto A. Bustamante
  • Patent number: 4734206
    Abstract: The invention relates, in one embodiment, to a method for separating coal particles from an aqueous slurry in which a multiple emulsion of oil in water is added to the aqueous slurry, the mixture is agitated to form agglomerates of coal particles, and the coal particles are separated from the remaining aqueous slurry. By the use of a multiple emulsion of oil in water, the amount of coal recovered per unit weight of oil is increased.
    Type: Grant
    Filed: June 25, 1986
    Date of Patent: March 29, 1988
    Assignee: Shell Oil Company
    Inventors: Eric J. Clayfield, Peter Sant
  • Patent number: 4720339
    Abstract: An improved method of separating non-sulfide value minerals from non-sulfide ores is disclosed. The improved method includes the step of adding a depressant selective for siliceous gangue minerals and materials to a flotation slurry previously conditioned with an anionic collector. In preferred embodiments, the depressants comprise copolymers or terpolymers derived from acrylamide units and N-acrylamidoglycolic acid units. The method provides generally improved recoveries of non-sulfide value minerals at higher grade, in a reduced number of flotation steps and at reduced consumption levels of flotation reagents.
    Type: Grant
    Filed: March 15, 1985
    Date of Patent: January 19, 1988
    Assignee: American Cyanamid Company
    Inventors: D. R. Nagaraj, Alan S. Rothenberg, Alexander S. Lambert
  • Patent number: 4704209
    Abstract: A process of flocculating suspended solids which comprises treating such suspension with an effective amount of a flocculant comprising a water-soluble terpolymer which contains sulfonate groups and has an RSV of at least 15.
    Type: Grant
    Filed: July 28, 1986
    Date of Patent: November 3, 1987
    Assignee: Nalco Chemical Company
    Inventors: Paul F. Richardson, Lawrence J. Connelly, Dodd W. Fong, Ralph W. Kaesler
  • Patent number: 4702844
    Abstract: A suspension may be flocculated using a water soluble substantially linear polymer having a single point intrinsic viscosity above 3 and that is a copolymer of two or more ethylenically unsaturated monomers including at least 0.5% by weight of monomer carrying pendant hydrophobic groups. The cationic polymers are novel. Preferred polymers are those in which the hydrophobic group is introduced as an allyl ether.
    Type: Grant
    Filed: August 15, 1985
    Date of Patent: October 27, 1987
    Assignee: Allied Colloids Limited
    Inventors: Peter Flesher, David Farrar, Malcolm Hawe, John Langley
  • Patent number: 4701264
    Abstract: Described herein is a process for flocculating taconite tailings which comprises (a) forming a concentrated aqueous solution from a water-soluble ter- or higher polymer water-in oil emulsion, (b) diluting said concentrated aqueous solution of ter- or higher polymer formed in step (a) with additional water, (c) mixing the diluted solution of (b) with taconite tailings under appropriate floc forming conditions and (d) allowing the suspended solids to settle to form an essentially clear aqueous supernatant.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: October 20, 1987
    Assignee: Union Carbide Corporation
    Inventor: David B. Braun
  • Patent number: 4701263
    Abstract: A process for flocculating solid fines from a solution comprising said solid fine and an organic liquid which comprises the steps of:(a) adding with mixing about 5 to about 10,000 ppm of an unneutralized or neutralized sulfonated polystyrene to said solution; and(b) heating at about 25.degree. C. to about 350.degree. C. for about 1 to abou 45 minutes the mixture of said solution and said neutralized or unneutralized polystyrene.
    Type: Grant
    Filed: December 23, 1985
    Date of Patent: October 20, 1987
    Assignee: Exxon Research and Engineering Company
    Inventors: Donald J. Mintz, Dennis G. Peiffer, Warren A. Thaler, Ilan Duvdevani
  • Patent number: 4696750
    Abstract: A process for flocculating solid fines from a solution comprising said solid fines and an organic liquid which comprises the steps of: (a) adding with mixing about 100 to about 500 ppm of an unneutralized or neutralized sulfonated polystyrene to said solution of solid fines; and (b) adding with mixing about 5 to about 25 weight percent of an antisolvent to the mixture of the sulfonated polystyrene and said solution of said solid fines.
    Type: Grant
    Filed: December 23, 1985
    Date of Patent: September 29, 1987
    Assignee: Exxon Research and Engineering Company
    Inventor: Jay Donald
  • Patent number: 4695371
    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.
    Type: Grant
    Filed: July 26, 1984
    Date of Patent: September 22, 1987
    Inventor: Arthur E. Starbuck
  • Patent number: 4693830
    Abstract: Aqueous dispersions of solids are readily flocculated in high brine-containing aqueous media using polymeric anionic flocculants containing from 5 to about 20 weight percent of repeating units containing a carboxyl group, e.g., sodium acrylate.
    Type: Grant
    Filed: September 23, 1985
    Date of Patent: September 15, 1987
    Assignee: The Dow Chemical Company
    Inventors: David C. Thornton, Mark J. McKinley
  • Patent number: 4690752
    Abstract: A process for separating and recovering non-metallic minerals, particularly phosphate, from an ore containing non-uniform sized particles, including colloidal particles. The ore is slurried in an alkaline, aqueous solution with a dispersing agent. A flotation collector is added, and the mixture is contacted with a hydrophobic, high molecular weight, nonionic polymer to flocculate the fine particles and make them amenable to subsequent flotation. A second embodiment provides a process for the recovery of an upgraded non-metallic ore from ore slimes, such as phosphate slimes, utilizing a high molecular weight, polyacrylamide, anionic flocculating agent.
    Type: Grant
    Filed: April 3, 1985
    Date of Patent: September 1, 1987
    Assignee: Resource Technology Associates
    Inventor: Douglas R. Shaw
  • Patent number: 4676913
    Abstract: Coal liquors are clarified by contacting them with high molecular weight copolymers of from about 70 to about 99 mole percent of a nonionic water-soluble monomer such as acrylamide and from 1 to 30 mole percent of a cationic monomer such as methacryloylethyl trimethyl ammonium chloride or methacrylamidopropyl trimethyl ammonium chloride.
    Type: Grant
    Filed: February 6, 1986
    Date of Patent: June 30, 1987
    Assignee: The Dow Chemical Company
    Inventors: James P. Easterly, Jr., William C. Foshee, Jack C. Lamphere
  • Patent number: 4647382
    Abstract: Aqueous mineral slurries containing 10% by weight or more of finely divided mineral solids are flocculated prior to dewatering and/or thickening, and prepared for redispersion, by treating the slurries with polymers comprising at least about 1% by weight 2-acrylamido-2-methyl propyl sulfonic acid copolymerized with acrylamide and/or other suitable water-soluble monomers. The polymers must have a Brookfield viscosity of at least 7000 cps at 7.5% concentration in water. Flocculation of the mineral slurries with these polymers also provides improved re-dispersibility of the dewatered mineral in the filter cake. During redispersion, additional dry mineral may be added to obtain a final solids content as high as 70% or more. The Brookfield viscosity of the final high solids slurry comprising a significant portion of filter cake treated with the flocculants of this invention is lower than that of untreated material.
    Type: Grant
    Filed: June 12, 1985
    Date of Patent: March 3, 1987
    Inventor: Andrew J. Sharpe, Jr.
  • Patent number: 4643822
    Abstract: A method of separating the constituent minerals of a mixture of minerals requires the introduction of fine particles of magnetic material such as finely ground particles of magnetite. The control of the zeta-potential of the minerals and particles of magnetic material provides heterocoagulation of the magnetized particles with one mineral but not the other to achieve separation. The method is ideally suitable for separating carbonates and phosphate ore and the separation process is enhanced by the addition of a surfactant such as oleate. The slurry is preferably subjected to low intensity magnetic separation to remove unattached particles of magnetic material which can be recycled to keep costs to a minimum.
    Type: Grant
    Filed: February 28, 1985
    Date of Patent: February 17, 1987
    Assignee: The Secretary of State for Trade and Industry in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland
    Inventor: Philip G. Parsonage
  • Patent number: 4618414
    Abstract: The invention relates to a process for separating mineral finest grain from coal slurries or washings obtained in coal processing, by treating the washing with a selective anionic dispersing agent for the finest grain, having a molecular weight of .ltoreq.10000 g/mol, and subsequent selective flocculation of the coal by means of a flocculating agent known per se.
    Type: Grant
    Filed: June 6, 1985
    Date of Patent: October 21, 1986
    Assignees: Chemische Fabrik Stockhausen GmbH, Saarbergwerke AG
    Inventors: Hans-Georg Hartan, Werner Padberg, Dietrich Muller
  • Patent number: 4615869
    Abstract: Phosphatic clay dispersions are modified by dispersing the phosphate matrix containing the clay in a dilute solution of selected acids prior to screening, sizing and other beneficiation operations.
    Type: Grant
    Filed: June 24, 1985
    Date of Patent: October 7, 1986
    Assignee: Mobil Oil Corporation
    Inventors: Ross A. Kremer, Stephen W. Saunders