Plural Cells Patents (Class 204/244)
  • Publication number: 20020005357
    Abstract: A waste treatment apparatus treats radioactive contaminated waste from a nuclear fuel material handling facility to decontaminate the radioactive contaminated waste by using an electrolytic molten salt, and reuses the electrolytic molten salt so that any effluents are not produced. Radioactive contaminated waste (10) from a nuclear fuel material handling facility is subjected to electrolysis by a molten salt electrolysis unit (20) to decontaminate the waste (10). The used salt (16) used for decontaminating the waste (10) is filtered to separate nuclear fuel materials (19) from the used salt (16). The filtered salt (18) is reused by the molten salt electrolysis unit (20). The salt adhering to the decontaminated waste (12) is recovered by an evaporating unit (59), and the recovered salt (15) is reused by the molten salt electrolysis unit (20).
    Type: Application
    Filed: August 29, 2001
    Publication date: January 17, 2002
    Inventors: Naruhito Kondo, Reiko Fujita
  • Patent number: 6248227
    Abstract: A non-carbon, metal-based slow-consumable anode of a cell for the electrowinning of aluminium self-forms during normal electrolysis an electrochemically-active oxide-based surface layer (20). The rate of formation (35) of the layer (20) is substantially equal to its rate of dissolution (30) at the surface layer/electrolyte interface (25) thereby maintaining its thickness substantially constant, forming a limited barrier controlling the oxidation rate (35). The anode (10) usually comprises an alloy of iron with at least one of nickel, copper, cobalt or zinc which during use forms an oxide surface layer (20) mainly containing ferrite.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: June 19, 2001
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Jean-Jacques Duruz
  • Patent number: 6221232
    Abstract: An electrolytic refining method for gallium by depositing refined gallium on a cathode in an electrolytic solution using a melted raw gallium material as an anode in an electrolytic cell is disclosed, comprising applying a centrifugal force to the melted raw gallium material and discharging out a scum gathered in the central portion of the cell.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: April 24, 2001
    Assignee: Dowa Mining Co., Ltd.
    Inventors: Kenichi Tayama, Nagayasu Yanata, Kishio Tayama
  • Patent number: 6210549
    Abstract: A fluorine generating cell apparatus, system, and method for the production of fluorine gas having an electrolyte melt flow circulation, a corrosion resistant anode connection, a separation skirt aiding in the circulation of the electrolyte melt, having a controlled gas recombination fail-safe, and a cathode arrangement enhancing efficiency and anode life by providing enhanced effective surface area for each anode.
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: April 3, 2001
    Inventor: Larry A. Tharp
  • Patent number: 6146513
    Abstract: The present invention includes uranium-bearing ceramic phase electrodes and electrolysis apparatus and electrolysis methods featuring same, including methods of metal production and the like by the electrolytic reduction of oxides or salts of the respective metals. More particularly, the invention relates to an inert type electrode composition, and methods for fabricating electrode compositions, useful in the electrolytic production of such metals. The present invention also includes an inert-type electrode composition, and methods for fabricating electrode compositions, used in processes for generating energy from fossil fuels.
    Type: Grant
    Filed: December 31, 1998
    Date of Patent: November 14, 2000
    Assignee: The Ohio State University
    Inventors: Kenneth H. Sandhage, Robert L. Snyder
  • Patent number: 6139704
    Abstract: Carbon-containing components of cells for the production of aluminium by the electrolysis of alumina dissolved in a cryolite-based molten electrolyte are protected from attack by liquid and/or gaseous components of the electrolyte in the form of elements, ions or compounds, by a refractory boride coating applied from a slurry composed of pre-formed particulate refractory boride in a colloidal carrier which is dried and heated to consolidate the coating.
    Type: Grant
    Filed: January 22, 1999
    Date of Patent: October 31, 2000
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Jainagesh A. Sekhar
  • Patent number: 6129821
    Abstract: In a metallic Mg electrolyzing device provided with a plurality of electrolytic cells for forming metallic Mg, promotion of current efficiency in each electrolytic cell and decrease in electric power consumption rate are aimed at. In order to transport the Cl.sub.2 gas produced as a byproduct in the plurality of electrolytic cells to a Cl.sub.2 gas refining equipment, gas from the plurality of electrolytic cells is collectively sucked by use of a blower installed in the main pipe. And an automatic valve is installed in each of the branch pipes which branch out from the main pipe and introduce the Cl.sub.2 gas from each electrolytic cell to the main pipe. Each automatic valve is gate type, and its positioner is driven/controlled by air pressure. The suction pressure for sucking Cl.sub.2 gas in the plurality of electrolytic cells is detected and the opening degree of the automatic valves is automatically controlled so that each detected pressure is controlled to the target value.
    Type: Grant
    Filed: February 18, 1999
    Date of Patent: October 10, 2000
    Assignee: Alcan International Limited
    Inventor: Takashi Kamitahira
  • Patent number: 6117302
    Abstract: A process and apparatus are disclosed for electrolytically smelting alumina to produce aluminum metal, including providing a combination solid oxide fuel cell and electrolytic smelting cell for the production of aluminum from refined alumina positioned near tile solid oxide fuel cell. In one aspect, an alumina ore refinery for producing the refined alumina is positioned near the solid oxide fuel cell, and refined alumina is passed at a temperature of at least 900.degree. C. directly from the alumina ore refinery to the electrolytic smelting cell. In one aspect, the solid oxide fuel cell incorporates a planar construction having a solid state cathode material of lanthanum strontium manganate, a solid electrolyte of yttria stabilized zirconia, and a nickel/yttria stabilized zirconia cermet anode.
    Type: Grant
    Filed: August 18, 1998
    Date of Patent: September 12, 2000
    Assignee: Aluminum Company of America
    Inventor: David J. Roha
  • Patent number: 6103090
    Abstract: A non-carbon, metal-based high temperature resistant anode of a cell for the production of aluminium has a metal-based substrate coated with one or more electrically conductive adherent applied layers, at least one electrically conductive layer being electrochemically active. The electrochemically active layer contains one or more electrocatalysts fostering the oxidation of oxygen ions as well as fostering the formation of biatomic molecular gaseous oxygen to inhibit ionic and/or monoatomic oxygen attack of the metal-based substrate. The electrocatalyst can be iridium, palladium, platinum, rhodium, ruthenium, silicon, tin, zinc, Mischmetal oxides and metals of the Lanthanide series. The applied layer may further comprise electrochemically active constituents from oxides, oxyfluorides, phosphides, carbides, in particular spinels such as ferrites.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: August 15, 2000
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Jean-Jacques Duruz
  • Patent number: 6077415
    Abstract: A composite, high-temperature resistant, non-carbon metal-based anode of a cell for the electrowinning of aluminium comprises a metal-based core structure of low electrical resistance, for connecting the anode to a positive current supply, coated with a series of superimposed, adherent, electrically conductive layers. These layers consist of at least one layer on the core structure constituting a barrier substantially impervious to monoatomic oxygen and molecular oxygen; one or more intermediate, protective layers on the oxygen barrier layer which remain inactive in the reactions for the evolution of oxygen gas; and an electrochemically active layer for the oxidation reaction of oxygen ions present at the anode/electrolyte interface into nascent monoatomic oxygen, as well as for subsequent reaction for the formation of gaseous biatomic oxygen.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: June 20, 2000
    Assignee: Moltech Invent S.A.
    Inventors: Jean-Jacques Duruz, Vittorio de Nora
  • Patent number: 6063247
    Abstract: Lithium chloride improves electrolytic cell efficiency and performance when included in the electrolyte. Self-aligning cell diaphragms improve cell efficiency and reduce maintenance.
    Type: Grant
    Filed: August 7, 1998
    Date of Patent: May 16, 2000
    Assignee: E.I. du Pont de Nemours and Company
    Inventors: Oswald Robert Bergmann, Howard M. Blank, Russell Bertrum Diemer, Jr., David Jain, Thomas A. Messing, Walter John Simmons
  • Patent number: 6030518
    Abstract: Aluminum is produced by electrolytic reduction of alumina in a cell having a cathode, an inert anode and a molten salt bath containing metal fluorides and alumina. The inert anode preferably contains copper, silver and oxides of iron and nickel. Reducing the molten salt bath temperature to about 900-950.degree. C. lowers corrosion on the inert anode constituents.
    Type: Grant
    Filed: September 10, 1997
    Date of Patent: February 29, 2000
    Assignee: Aluminum Company of America
    Inventors: Robert K. Dawless, Siba P. Ray, Robert B. Hosler, Robert L. Kozarek, Alfred F. LaCamera
  • Patent number: 5935394
    Abstract: An electrolytic cell for the recovery of metal from a molten electrolyte and an electrode assembly for use in such a cell. The cell (10) comprises an electrode assembly consisting of an anode (17), a cathode (19) and one or more bipolar electrodes (18) disposed between the anode and the cathode so as to form interpolar spaces (16) in which electrolysis occurs. In the electrode assembly, the bipolar electrode (if there is only one) or the innermost bipolar electrode (if there are more than one) substantially surrounds the anode and forms a single mechanical and electrical entity. The cathode in turn preferably substantially surrounds the one or more bipolar electrodes. The electrode assembly comprising the cathode and bipolar electrode(s) is preferably unitary, forming an electrode cassette that can be assembled outside a cell and then introduced into, or withdrawn from, the cell as a single self-supporting unit.
    Type: Grant
    Filed: January 13, 1998
    Date of Patent: August 10, 1999
    Assignee: Alcan International Limited
    Inventors: Olivo Giuseppe Sivilotti, Meine Vandermeulen, Junkichi Iseki
  • Patent number: 5873993
    Abstract: The present invention concerns a procedure for continuous or batch production in one or possibly more steps in one or more furnaces of silicon metal (Si), possibly silumin (AlSi alloys) and/or aluminium metal (Al) in the required conditions in a melting bath, preferably using feldspar or feldspar containing rocks dissolved in a fluoride and process equipment for implementing the procedure. Highly pure silicon is produced by electrolysis (step I) in a first furnace comprising a replaceable carbon anode (3) located at the bottom of the furnace and a carbon cathode (1) located at the top of the furnace. For the production of silumin the Si-poor residual electrolyte from step I is transferred to a second furnace and aluminium metal is added (step II). Aluminium metal is produced in a third furnace (step III) by electrolysis after Si has been removed in step I and possibly in step II.
    Type: Grant
    Filed: February 25, 1997
    Date of Patent: February 23, 1999
    Inventor: Jan Stubergh
  • Patent number: 5855757
    Abstract: The present invention provides a new and useful process for the production of a molten metal by electrolysis in an electrolytic cell having an electrolysis compartment, a metal recovery compartment, and a partition separating upper parts of said compartments, said process comprising: electrolysing in said electrolysis compartment an electrolyte containing a fused salt of said metal said electrolyte being of greater density than said metal; continuously withdrawing the product metal mixed with said electrolyte in a stream from said electrolysis compartment to a top part of said metal recovery compartment; allowing said metal to form in said metal recovery compartment a pad floating on said electrolyte; maintaining said pad out of contact with said partition; and recovering said pad.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: January 5, 1999
    Inventor: Olivo Sivilotti
  • Patent number: 5830335
    Abstract: An arrangement of busbars for conducting direct electric current via busbars from the cathode bar ends of a longitudinally arranged electrolytic cell--in particular for manufacturing aluminum--to the traverse beam ends of the next cell is such that a fraction of the cathode bar ends, on each long side of the cell, is joined to form partial busbars (A, B) which are led from the long side of the next cell perpendicular to their longitudinal direction (x) under the cell and under the cell to a collector busbar (C) which is led under the cell in the longitudinal direction (x) to the downstream end of the traverse beam. As a result of the chosen arrangement of both partial busbars (A, B) and the collector busbar (C) in the form of a "T", optimum compensation is obtained for electromagnetic field forces and, as a result, excellent stability of the electrolytic cell.
    Type: Grant
    Filed: December 24, 1996
    Date of Patent: November 3, 1998
    Assignee: Alusuisse Technology & Management Ltd.
    Inventor: Jacques Antille
  • Patent number: 5725744
    Abstract: An electrolysis cell for the production of aluminum by the electrolysis of alumina dissolved in a molten halide electrolyte using a multimonopolar arrangement of substantially non-consumable anodes and cathodes with facing operative surfaces which are upright or at a slope and are spaced in a substantially parallel relationship, enabling operation at low and/or current density with an acceptable production per unit self-lowered area. The operative surface area of the anodes and the cathodes is high due to their upright sloping configuration. Operative surfaces of the anodes and possibly of the cathodes can be increased by making them porous, preferably with their articulated skeletal structure, e.g. with a porous active part on opposite faces of a central current feeder.
    Type: Grant
    Filed: April 24, 1996
    Date of Patent: March 10, 1998
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Jean-Jacques Duruz
  • Patent number: 5650053
    Abstract: A cathode-anode arrangement for use in an electrolytic cell is adapted for electrochemically refining spent nuclear fuel from a nuclear reactor and recovering purified uranium for further treatment and possible recycling as a fresh blanket or core fuel in a nuclear reactor. The arrangement includes a plurality of inner anodic dissolution baskets that are each attached to a respective support rod, are submerged in a molten lithium halide salt, and are rotationally displaced. An inner hollow cylindrical-shaped cathode is concentrically disposed about the inner anodic dissolution baskets. Concentrically disposed about the inner cathode in a spaced manner are a plurality of outer anodic dissolution baskets, while an outer hollow cylindrical-shaped is disposed about the outer anodic dissolution baskets. Uranium is transported from the anode baskets and deposited in a uniform cylindrical shape on the inner and outer cathode cylinders by rotating the anode baskets within the molten lithium halide salt.
    Type: Grant
    Filed: November 24, 1995
    Date of Patent: July 22, 1997
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Eddie C. Gay, William E. Miller, James J. Laidler
  • Patent number: 5415742
    Abstract: A process for electrowinning metal in a low temperature melt is disclosed. The process utilizes an inert anode for the production of metal such as aluminum using low surface area anodes at high current densities.
    Type: Grant
    Filed: October 15, 1993
    Date of Patent: May 16, 1995
    Assignee: Aluminum Company of America
    Inventors: Alfred F. La Camera, Kathleen M. Tomaswick, Siba P. Ray, Donald P. Ziegler
  • Patent number: 5364513
    Abstract: A body of carbonaceous or other material for use in corrosive environments such as oxidizing media or gaseous or liquid corrosive agents at elevated temperatures, in particular in molten salts such as cryolite, is coated with a protective surface coating which improves the resistance of the body to oxidation or corrosion and which may also enhance the bodies electrical conductivity and/or its electrochemical activity. The protective coating is applied in one or more layers from a colloidal slurry containing reactant or non-reactant substances, or a mixture of reactant and non-reactant substances, in particular mixtures containing silicon carbide and molybdenum silicide or silicon carbide and silicon nitride, which when the body is heated to a sufficient elevated temperature reaction sinter as a result of micropyretic reaction and/or sinter without reaction to form the protective coating.
    Type: Grant
    Filed: June 12, 1992
    Date of Patent: November 15, 1994
    Assignee: Moltech Invent S.A.
    Inventors: Jainagesh A. Sekhar, Vittorio de Nora
  • Patent number: 5362366
    Abstract: A novel anode-cathode arrangement for the electrowinning of aluminum from alumina dissolved in molten sales, consisting of an anode-cathode double-polar electrode assembly unit or a continuous double polar assembly in which the anode and cathode are bound together and their interelectrode gap is maintained substantially constant by connections made of materials of high electrical, chemical, and mechanical resistance. Novel, multi-double-polar cells for the electrowinning of aluminum contain two or more of such anode-cathode double-polar electrode assembly units. This arrangement permits the removal of reimmersion into any of the anode-cathode double-polar electrode assembly units during operation of the multi-double-polar cell whenever the anode and or the cathode or any part of the electrode unit needs reconditioning for efficient cell operation.
    Type: Grant
    Filed: April 27, 1992
    Date of Patent: November 8, 1994
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Jainagesh A. Sekhar
  • Patent number: 5286353
    Abstract: The present invention relates to a new electrolysis cell for the fusion electrolytic extraction of aluminum wherein the anode blocks are connected to one another using a compressed granulate packing. The invention also relates to a novel electrolytic cell wherein the cathode blocks are separated one from another and have sloped or curved upper surfaces allowing newly formed aluminum to drain into an underlying receptacle area.
    Type: Grant
    Filed: June 2, 1992
    Date of Patent: February 15, 1994
    Assignee: VAW Aluminium A.G.
    Inventor: Siegfried Wilkening
  • Patent number: 5286359
    Abstract: An electrolysis cell for producing metals by electrolytic reduction of molten baths which includes non-consumable inert anodes and refractory hard metal cathode elements. The cathode elements are replaceably mounted in the electrolysis cell and have inclined planar working surfaces which have grooves therein. A method for producing metals by use of the electrolysis cell includes utilizing the grooves to control the release of anode gases.
    Type: Grant
    Filed: May 20, 1991
    Date of Patent: February 15, 1994
    Assignee: Reynolds Metals Company
    Inventors: Nolan E. Richards, Alton T. Tabereaux
  • Patent number: 5284562
    Abstract: An oxidation resistant, non-consumable anode, for use in the electrolytic reduction of alumina to aluminum, has a composition comprising copper, nickel and iron. The anode is part of an electrolytic reduction cell comprising a vessel having an interior lined with metal which has the same composition as the anode. The electrolyte is preferably composed of a eutectic of AlF.sub.3 and either (a) NaF or (b) primarily NaF with some of the NaF replaced by an equivalent molar amount of KF or KF and LiF.
    Type: Grant
    Filed: April 17, 1992
    Date of Patent: February 8, 1994
    Assignees: Electrochemical Technology Corp., Brooks Rand, Ltd.
    Inventors: Theodore R. Beck, Richard J. Brooks
  • Patent number: 5254232
    Abstract: Improved electrolytic cells for producing metals by the electrolytic reduction of a compound dissolved in a molten electrolyte are disclosed. In the improved cells, at least one electrode includes a protective layer comprising an oxide of the cell product metal formed upon an alloy of the cell product metal and a more noble metal.In the case of an aluminum reduction cell, the electrode can comprise an alloy of aluminum with copper, nickel, iron, or combinations thereof, upon which is formed an aluminum oxide protective layer.
    Type: Grant
    Filed: February 7, 1992
    Date of Patent: October 19, 1993
    Assignee: Massachusetts Institute of Technology
    Inventor: Donald R. Sadoway
  • Patent number: 5242563
    Abstract: A molten salt reactor for potentiostatic electroplating that includes a rtor chamber defined by a peripheral wall, a bottom wall and a top cover. The bottom wall of the reactor chamber has an opening, to which a first end of a gas inlet conduit is attached so as to be in fluid communication with the reactor chamber. A crucible support platform is positioned within the reactor chamber, and a crucible for holding a molten salt is mounted thereon. A furnace substantially surrounds the peripheral wall of the reactor chamber and the first end of the gas inlet conduit. The crucible support platform is electrically insulated from the reactor chamber. An inert gas flows from the gas inlet conduit, through a lower portion of the reactor chamber, past the crucible support platform, through an upper portion of the reactor chamber, and to a gas outlet in the upper portion of the reactor chamber.
    Type: Grant
    Filed: March 12, 1992
    Date of Patent: September 7, 1993
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Kurt H. Stern, Ralph M. Hess
  • Patent number: 5240569
    Abstract: The system includes at least one electrolysis cell having a principal direction of current flow. The electrolysis cell has two electrode surfaces whose mean surface planes are substantially parallel, separated by a fluid electrolyte layer.Separate electric current conducting means, energized by an electric power source and independent of the electrolysis circuit elements are so arranged and constructed with respect to the cell to increase the average component of the magnetic field substantially parallel to the mean electrode surfaces within the fluid electrolyte layer. This increase in the magnetic field is relative to the magnetic field due solely to the electrolysis current. A flow return conduit is included for connecting at least one entrance port of the electrolysis cell to a least one exit port of the electrolysis cell. The ports are disposed substantially parallel to the pressure gradient formed by the magnetic forces present during operation.
    Type: Grant
    Filed: September 30, 1991
    Date of Patent: August 31, 1993
    Assignee: Rockwell International Corporation
    Inventor: Robert D. Waldron
  • Patent number: 5013413
    Abstract: The invention relates to an apparatus for the continuous production of a polyvalent metal by electrolysis of a halide of the metal in a bath of at least one melted salt. The apparatus comprises an electrodismutation cell and a prereduction cell in a contiguous configuration sharing a common wall in the form of a grid which is electrically insulated from the cell walls. The electrodismutation cell includes at least one deposition cathode and at least two anodes which are connected to an at least partly direct current. The prereduction cell includes at least one anode and a cathode constituted by the grid, the anode and cathode being separated by a diaphragm and connected to an at least partly direct current power supply. Means are provided to cause bath flow by forced convection through the grid to produce a top-to-bottom movement in the electrodismutation cell and a bottom-to-top movement in the prereduction cell.
    Type: Grant
    Filed: April 16, 1990
    Date of Patent: May 7, 1991
    Assignee: Compagnie Europeenne du Zirconium Cezus of Tour Manhattan
    Inventors: Airy-Pierre Lamaze, Patrick Paillere
  • Patent number: 4976841
    Abstract: Busbar arrangements for aluminum electrolytic cells. In a first aspect, the invention provides at least one generally horizontal collector busbar on each side of the cell and a number of current tapping points along each collector busbar so that current flows along the collector busbar in opposite directions on each side of the taps. This produces changes of sign in the vertical component of the magnetic field acting on the pad in the longitudinal direction and helps to prevent pad instabilities. In a second aspect, the current taps for the collector busbars are vertically disposed so as to convey current well below the level of the metal pad so that adverse magnetic effects caused by further distribution of the current are minimized.
    Type: Grant
    Filed: October 19, 1989
    Date of Patent: December 11, 1990
    Assignee: Alcan International Limited
    Inventors: Richard F. Boivin, Jean-Paul R. Huni, Robert LeBlanc
  • Patent number: 4960501
    Abstract: An electrolytic cell for producing a metal, e.g. magnesium, by electrolysis has a housing in which are disposed one or more electrode assemblies each comprising a cathode assembly providing a vertical cavity in which are disposed an anode and one or more bipolar electrode assemblies disposed between the anode and cathode assembly, and baffles for preventing or impeding flow of electrolyte between adjacent cathode assemblies and/or between each cathode assembly and an adjacent wall of the housing.
    Type: Grant
    Filed: March 12, 1989
    Date of Patent: October 2, 1990
    Assignee: Alcan International Limited
    Inventor: Olivo G. Sivilotti
  • Patent number: 4944859
    Abstract: An electrolytic cell recovery of metal comprising a first partition wall provided with partition openings situated beneath the level of an electrobath and disposed between a dissociated metal recovery chamber and an electrolytic chamber having an anode and a cathode and a second partition wall adapted to constitute an intermediate chamber between the first and second partition walls for recovery of dissociated Cl.sub.2 gas; and also the arrangement of bipolar electrodes in the electrolytic cell and the shape of a control plate for preventing the deposition of sludge.
    Type: Grant
    Filed: March 29, 1989
    Date of Patent: July 31, 1990
    Assignee: Toho Titanium Co., Ltd.
    Inventors: Hiroshi Matsunami, Kunio Maehara, Susumu Kosemura
  • Patent number: 4904356
    Abstract: A carbon block acts as a cell electrode. Channels are formed in its face which is to face the cell diaphragm. The channels provide an interconnected network including retention pools arranged to hold, release, break up and mix a liquid stream passing through them.
    Type: Grant
    Filed: May 1, 1989
    Date of Patent: February 27, 1990
    Assignee: National Research Development Corporation
    Inventor: Derek J. Fray
  • Patent number: 4882017
    Abstract: A method for making light metal-alkali metal master alloy using alkali metal containing scrap comprises: (a) establishing an electrolytic cell divided into two or more laterally adjacent areas by porous alkali metal ion transport means, said cell including a first cell area supplied with alkali metal-containing scrap and a second cell area consisting essentially of molten light metal; (b) supplying current to this cell for transporting alkali metal ions from the first cell area to the second cell area; (c) forming master alloy by combining these ions with the molten light metal in said second cell area; and (d) withdrawing master alloy from the second cell area. An apparatus for making aluminum-lithium or magnesium-lithium master alloy using the lithium from aluminum-lithium alloy scrap is also disclosed.
    Type: Grant
    Filed: June 20, 1988
    Date of Patent: November 21, 1989
    Assignee: Aluminum Company of America
    Inventor: Mark L. Weaver
  • Patent number: 4865701
    Abstract: Alumina is reduced to molten aluminum in an electrolytic cell containing a molten electrolyte bath composed of halide salts and having a density less than alumina and aluminum and a melting point less than aluminum. The cell comprises a plurality of vertically disposed, spaced-apart, non-consumable, dimensionally stable anodes and cathodes. Alumina particles are dispersed in the bath to form a slurry. Current is passed between the electrodes, and oxygen bubbles form at the anodes, and molten aluminum droplets form at the cathodes. The oxygen bubbles agitate the bath and enhance dissolution of the alumina adjacent the anodes and inhibit the alumina particles from settling at the bottom of the bath. The molten aluminum droplets flow downwardly along the cathodes and accumulate at the bottom of the bath.
    Type: Grant
    Filed: August 31, 1988
    Date of Patent: September 12, 1989
    Inventors: Theodore R. Beck, Richard J. Brooks
  • Patent number: 4720333
    Abstract: The invention concerns a superstructure for a tank for the production of aluminum using the Hall-Heroult process by the electrolysis of alumina in molten cryolite, the tank being formed by a rigid metal heat-insulated casing of elongate parallelepipedic shape, the two ends of which are referred to as heads, and a superstructure formed by at least one rigid beam disposed along the long length of the casing, supporting in particular the anodic bus and the anodes and resting at its two ends on supports disposed at the two head ends of the tank, said superstructure being characterized in that each rigid beam is supported on at least one intermediate gantry in the central part thereof. The gantry may comprise four legs so as to constitute an inherently stable structure or it may be formed by two half-elements each provided with two legs. Preferably, each rigid beam is divided into two equal portions, the central ends of which are supported on the gantry.
    Type: Grant
    Filed: May 29, 1986
    Date of Patent: January 19, 1988
    Assignee: Aluminium Pechiney
    Inventors: Christian Duval, Bernard Langon, Michel Leroy, Alain Noizet
  • Patent number: 4713161
    Abstract: The invention relates to a circuit for electrical connection between two successive cells of a series or row, designed for the production of aluminium by electrolysis of alumina dissolved in molten cryolite by the Hall-Heroult process at an intensity of at least 150 kA and possibly attaining from 500 to 600 kA. The circuit for the electrical supply of the cells comprises, in addition to the circuit 8 for the supply of electrolysis current, a distinct circuit 17 for correcting and balancing the magnetic fields which is formed by conductors which are substantially parallel to the axis of the series and are traversed by a direct current in the same direction as the electrolysis current which creates, in the cells, a vertical correcting magnetic field directed downwards close to the left-hand heads of the cells and directed upwards close to the right-hand heads of the cells.
    Type: Grant
    Filed: June 5, 1986
    Date of Patent: December 15, 1987
    Assignee: Aluminium Pechiney
    Inventors: Joseph Chaffy, Bernard Langon, Michel Leroy
  • Patent number: 4696730
    Abstract: The invention relates to a circuit for electrical connection between the cells of a row designed for the production of aluminium by electrolysis, by the Hall-Heroult process. It is applied to rows of cells arranged transversely to the axis of the row operating at a current higher than 250,000 amperes and possibly attaining from 300 to 600 kA.
    Type: Grant
    Filed: June 5, 1986
    Date of Patent: September 29, 1987
    Assignee: Aluminium Pechiney
    Inventors: Joseph Chaffy, Bernard Langon
  • Patent number: 4683047
    Abstract: An aluminium potline comprises rows of reduction cells with the cells arranged transversely in each row. The invention provides an asymmetric arrangement of busbars (1, 1', 2, 2') for conducting current from the upstream collector bars 16 of an aluminium electrolytic reduction cell 10 underneath the cell to the next downstream cell 12 in the row. One or more of the busbars is displaced longitudinally of the cell towards the end facing a magnetically dominating neighboring row of cells. The extent of the displacement is such as to counteract the magnetic field induced by the neighboring row.
    Type: Grant
    Filed: December 27, 1985
    Date of Patent: July 28, 1987
    Assignee: Alcan International Limited
    Inventors: Richard F. Boivin, Jean-Paul R. Huni, Vinko Potocnik
  • Patent number: 4668352
    Abstract: A process for automatically going into the mode for increased suction extraction of the gases emitted by the tanks of series for the production of aluminium by igneous electrolysis using the Hall-Heroult process, each tank being closed around its periphery by a plurality of removable covers which are disposed in substantially sealed relationship with each other and between each thereof and their support means on the periphery of the tank, the gases being collected over each tank by at least one duct connected to a centralized suction extraction system.The temperature of the gases in the duct is continuously measured. Opening of at least one cover gives rise to an abrupt drop in temperature, which makes it possible to put the system into the increased suction extraction mode, which will be automatically stopped when, all the covers being closed again, the temperature of the gases will substantially resume its initial value.The power required for the suction system is thus substantially reduced.
    Type: Grant
    Filed: December 31, 1985
    Date of Patent: May 26, 1987
    Assignee: Aluminum Pechiney
    Inventors: George Duprat, Bernard Langon, Benoit Sulmont
  • Patent number: 4654133
    Abstract: The invention concerns a tank for the production of aluminum using the Hall-Heroult process by the electrolysis of alumina in a molten cryolite-base bath in an assembly formed by the grouping in series of a plurality of aligned tanks, each tank being formed by a rectangular metal casing whose major axis is perpendicular to the axis of the series and whose interior comprises a heat-insulating lining, a cathode formed by the juxtaposition in sealed relationship of carbonaceous blocks in which metal cathodic bars are sealed, the two ends of the cathodic bars, which issue from the carbonaceous blocks, forming the cathodic outputs which extend to the outside of the casing on the upstream and downstream sides thereof, in relation to the direction of flow of the current in the series, and to which there are connected the conductors for making an electrical connection with the following tank in the series; wherein in accordance with the invention, and in order to make the ohmic resistance of the two groups of upstrea
    Type: Grant
    Filed: January 14, 1986
    Date of Patent: March 31, 1987
    Assignee: Aluminium Pechiney
    Inventors: Spyridon Casdas, Bernard Langon, Laurent Michard
  • Patent number: 4638441
    Abstract: Disclosed is a system for measuring cell potentials in an aluminum potline having a plurality of cells connected in series. The system enables better control of the cells than the current method which calculates cell resistance on the basis of measured cell potentials and potline current but an assumed value of back e.m.f. The present invention uses corrected voltage measurements and provides a decentralized, current independent cell potential measuring system which converts simultaneously all cell potentials during a normal integration period (e.g. 1 second) into a value corresponding to the potline current when it is at its normal (set-point) value. Simultaneously, various possible back e.m.f. values are measured with the same current relationship and computations made of the error caused by the non-ohmic portion of the cell potential when the current deviates from its normal (set-point) value. Sudden changes in current enable correct values of back e.m.f. to be determined.
    Type: Grant
    Filed: May 31, 1984
    Date of Patent: January 20, 1987
    Assignee: R.F.J. Associates Limited
    Inventor: Andrew E. Deczky
  • Patent number: 4613414
    Abstract: An electrolytic cell for metal, particularly Mg, production includes a cathode or intermediate bipolar electrode having a cathodic face provided with a plurality of small cavities shaped to trap droplets of molten metal formed during electrolysis. The cavities help the metal droplets to coalesce and reduce the extent of back reaction with e.g. chlorine generated at the anode.
    Type: Grant
    Filed: April 4, 1985
    Date of Patent: September 23, 1986
    Assignee: Alcan International Limited
    Inventors: Olivo G. Sivilotti, Junkichi Iseki
  • Patent number: 4604177
    Abstract: A cell for producing magnesium or other metal by electrolysis of molten chloride or other electrolyte comprises at least one electrode assembly of an anode 24, at least one intermediate bipolar electrode 28, 30, 32, 34 and a cathode 26 defining generally vertical interelectrode spaces between them. To minimize current leakage, the intermediate bipolar electrodes preferably almost completely surround the anode including the edges and the bottom.In operation, a metal/electrolyte mixture is swept up the interelectrode spaces by generated chlorine gas and spills out over the cathode into a duct 20 behind the cathode, the duct including a restricted passage 58 for degassing and an inverted channel 62 to collect product metal and convey it to a metal collection chamber 18.The electrolyte surface is preferably maintained at about the level of the top edges of the intermediate bipolar electrodes by means of a level control device 22 submerged in electrolyte in the metal collection chamber.
    Type: Grant
    Filed: February 11, 1985
    Date of Patent: August 5, 1986
    Assignee: Alcan International Limited
    Inventor: Olivo G. Sivilotti
  • Patent number: 4601804
    Abstract: The thermally insulated cell comprises: a trough with a steel shell which is surrounded by an outer wall, is lined with a material which is resistant to electrolyte and high temperatures, and is closed by a lid; an electrolyte based on alkali chlorides; segregation wells for the addition of aluminum which is to be purified and for the precipitation of impurity crystals; a supply means which is used to feed-in electrolyte material and is also conceived as a waste gas extractor; a collection and run-off system for the high purity aluminum. Provided in the interior of the cell are bipolar electrode units which are connected electrically in series and are arranged immersed in the electrolyte parallel to the end electrodes. The electrode units comprise graphite frames closed and sealed off by a diaphragm plate, which can be wet by the electrolyte but not by the aluminum. The interpolar distance between the inner side of the diaphragm plate and the cathodic graphite frame is preferably 10-25 mm.
    Type: Grant
    Filed: July 12, 1984
    Date of Patent: July 22, 1986
    Assignee: Swiss Aluminium Ltd.
    Inventor: Sylvestre Vire
  • Patent number: 4592821
    Abstract: The present invention concerns an electrolysis tank for the production of aluminum by means of the Hall-Heroult process, which operates at above 250,000 amperes, in particular from 270,000 to 320,000 amperes.The connection between each riser (7) and the anodic bus bar (5) is made by way of flexible electrical conductors (8); the central riser (7C) is disposed on the axis of the series, the two intermediate risers (7B, 7D) and the two equally spaced lateral risers (7A, 7E) through which substantially equal current strengths flow are connected to six upstream cathodic collectors (3), two central collectors (3A, 3B) two intermediate collectors (3C, 3D) and two lateral collectors (3E, 3F), and three downstream cathodic collectors (4), a central collector (4A) and two lateral collectors (4B, 4C).Equipotential connections provide for balancing of the current between the different sections of the upstream and downstream collectors.
    Type: Grant
    Filed: October 2, 1984
    Date of Patent: June 3, 1986
    Assignee: Aluminium Pechiney
    Inventors: Maurice Keinborg, Bernard Langon, Joseph Chaffy
  • Patent number: 4585527
    Abstract: An electrolytic cell comprising an anode and cathode and a gasket of an electrically insulating composition in which the gasket is made of an electrically insulating composition which comprises a homogeneous mixture of an elastomeric polymer and at least 15%, and optionally up to 70%, of polytetrafluoroethylene by weight of the composition. Also a gasket suitable for use in an electrolytic cell, and a process of electrolysis which is operated in the electrolytic cell. Aqueous alkali metal chloride solution may be electrolysed in the electrolytic cell.
    Type: Grant
    Filed: January 25, 1985
    Date of Patent: April 29, 1986
    Assignee: Imperial Chemical Industries PLC
    Inventors: Herbert S. Northway, Norman Tattam
  • Patent number: 4511845
    Abstract: The salinometer is based on a direct determination of the conductivity ratio R.sub.t =(Cx/Cs).sub.t of sample water to standard seawater in a two channel, dual-cell, continuous-flow system. Each of the channels includes a conductivity cell with four electrodes immersed in sequence in the water flow. Two of the electrodes are current electrodes and the other two electrodes are potential electrodes. The standard water and the sample water pumped into their respective channels, are maintained at a common temperature by heat exchangers and a common bath. The salinometer circuitry include a first current source for driving a controlled current into the current electrodes of the conductivity cell to maintain a constant voltage across the potential electrodes. A second current source drives a current which is a linear function of the first controlled current into the current electrodes of the conductivity cell in the reference channel. The conductivity ratio R.sub.
    Type: Grant
    Filed: September 8, 1982
    Date of Patent: April 16, 1985
    Assignee: Canadian Patents & Development Limited
    Inventors: Thomas M. Dauphinee, Christopher G. M. Kirby
  • Patent number: 4510029
    Abstract: Directed to the electrolytic purification of molten magnesium chloride cell feed and to a covered cell design therefor wherein preferably a plurality of bipolar electrodes are employed. A current density of about 0.8 to about 1.5 amperes per square inch D.C. is employed, flow of the electrolyte through the cell proceeds in a non-turbulent manner through flow passages in the electrodes, and the solid impurities deposited electrolytically are removed periodically by mechanical action.
    Type: Grant
    Filed: May 18, 1984
    Date of Patent: April 9, 1985
    Assignee: AMAX Inc.
    Inventors: Ramaswami Neelameggham, John C. Priscu, Robert D. Toomey
  • Patent number: 4481085
    Abstract: An apparatus for electrolysis of MgCl.sub.
    Type: Grant
    Filed: March 16, 1983
    Date of Patent: November 6, 1984
    Inventor: Hiroshi Ishizuka
  • Patent number: 4474610
    Abstract: In electrolytic cells for producing aluminum in a side-by-side arrangement, a number of cathode bus bars connected to cathode current collector bars projected from upstream long side of each electrolytic cell are connected to at least one rising bus bars provided at upstream long side of an adjacent electrolytic cell provided on downstream side through at least one cathode bus bars provided in the space below the relevant cell and in parallel to the axial line of a row of electrolytic cells; the remaining number thereof are connected to rising bus bars provided at short ends of the adjacent electrolytic cell on the downstream side through cathode bus bars extending along outsides at the short ends of the relevant electrolytic cell, a number of cathode bus bars connected to cathode current collector bars projected from downstream long side of each electrolytic cell are connected to at least one rising bus bar provided on upstream long side of the adjacent electrolytic cell on the downstream side, and the remai
    Type: Grant
    Filed: April 22, 1983
    Date of Patent: October 2, 1984
    Assignee: Sumitomo Aluminium Smelting Company, Limited
    Inventors: Shozo Kato, Yasuhiko Ujimoto