With Feeding And/or Withdrawal Means Patents (Class 204/245)
  • Patent number: 4447301
    Abstract: This invention teaches a control to be used in smelting aluminum by the electrolysis breakdown of alumina (A1.sub.2 O.sub.3) in a molten electrolyte heated to approximately 950.degree.-1000.degree. C. The invention provides a sonic resonator and control that can accurately detect the resonant frequency of the resonator in the molten electrolyte. The resonator preferably is made with tubular side wall 1/4 of the sonic wavelength, or is a quarter wave resonator. A wave generator inputs a signal having a range of frequencies that includes the resonant frequency, so that a peak resonant output at the resonant frequency can be detected on an oscilloscope or like detector. This instantaneous resonant frequency is then checked against an accurate data base correlating the resonant frequencies of the resonator in the electrolyte at specific alumina concentrations normally experienced throughout the electrolysis cycle.
    Type: Grant
    Filed: October 29, 1982
    Date of Patent: May 8, 1984
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: Sin-Yan Shen
  • Patent number: 4443313
    Abstract: In an electrolytic reduction cell for the production of molten metal, particularly aluminium, by electrolysis of a less dense salt monolayer of ceramic shapes is located on the floor of the cell. Such shapes are formed of a ceramic material, wettable by molten aluminium, but not wettable by the cell electrolyte. The spacing between adjacent shapes and/or the apertures in individual shapes is selected such that interfaced surface forces prevent entry of electrolyte between the shapes. The shapes may be tiles, honeycombs, cylinders, tubes, balls etc. The product metal may be collected in a sump for periodic withdrawal from the cell or withdrawn continuously or at short intervals through a selective filter that permits passage of molten metal, but not of molten cell electrolyte, at low withdrawal rates.
    Type: Grant
    Filed: June 23, 1982
    Date of Patent: April 17, 1984
    Assignee: Alcan International Limited
    Inventors: Adam J. Gesing, John McIntyre, Meine Vandermeulen, Edward L. Cambridge, Thomas P. DeAngelis
  • Patent number: 4437964
    Abstract: The invention concerns a detachable assembly for spot feeding alumina to a tank for the production of aluminum. A fixed hopper is made integral with horizontal metal girders which form at least part of its side walls. The hopper is provided with a bottom aperture for discharge of alumina therethrough. An impervious metal case is positioned vertically in said hopper with the upper part of the case open and substantially at the level of the upper part of the hopper. The case has two substantially parallel vertical branches, the first branch opening, at its lower portion, outside the hopper, and the second branch opening, at its lower portion, inside the hopper, in the immediate vicinity and on the axis of the aperture for the discharge of alumina.
    Type: Grant
    Filed: May 19, 1983
    Date of Patent: March 20, 1984
    Assignee: Aluminium Pechiney
    Inventors: Jean-Louis Gerphagnon, Claude Wolter
  • Patent number: 4435255
    Abstract: The invention concerns a process and a device for controlled feed of alumina and halogen additives into a vat for production of aluminum by alumina electrolysis according to the Hall-Heroult technique.The alumina or the halogen additive, set aside by gravity into the storage means, is introduced into a volumetric feed regulator and dispatched under the effect of a jet of compressed air, as far as the orifice of introduction into the electrolysis vat, through a rigid system of pipes, in successive equal or unequal dosed quantities, at constant or variable time intervals. The device includes no moving piece which is subject to wear or abrasion.
    Type: Grant
    Filed: April 9, 1982
    Date of Patent: March 6, 1984
    Assignee: Aluminium de Grece
    Inventor: Spyridon Casdas
  • Patent number: 4431491
    Abstract: A process and apparatus for controlling the rate of introduction and the content of alumina to a tank for the production of aluminium by the electrolysis of dissolved alumina in a cryolite-base bath, the upper part of which forms a solidified crust, and wherein the alumina content is maintained within a narrow range, of between 1% and 3.5%, wherein the alumina is introduced directly into the molten cryolite bath by way of at least one opening which is kept open in the solidified crust and the rate at which the alumina is introduced is modulated relative to variations in the internal resistance of the tank during predetermined periods of time, with alternation of the cycles of introducing alumina at a slower rate and at a faster rate than the rate corresponding to normal consumption within the tank.
    Type: Grant
    Filed: July 20, 1981
    Date of Patent: February 14, 1984
    Assignee: Pechiney
    Inventors: Paul Bonny, Jean-Louis Gerphagnon, Gerard Laboure, Maurice Keinborg, Pierre Homsi, Bernard Langon
  • Patent number: 4420381
    Abstract: In the production of magnesium by electrolysis of a fused salt the metal is collected over a body of the fused salt under a heavily insulated cover to reduce heat loss from the molten metal under a substantially non-oxidizing atmosphere. The electrolyte is held down to a controlled temperature somewhat above the melting point of magnesium by means of a heat exchanger which projects into the fused electrolyte and is arranged so as to avoid significant uptake of heat from the supernatant molten metal. This arrangement permits the electrolyte temperature to be controlled with reduced formation of sludge and extended cell life by avoidance of exposure of the electrolyte to atmospheric moisture.
    Type: Grant
    Filed: February 8, 1982
    Date of Patent: December 13, 1983
    Assignee: Alcan International Limited
    Inventors: Olivo G. Silvilotti, Junkichi Iseki
  • Patent number: 4416489
    Abstract: A chisel for a crust breaking facility for breaking through the solidified crust of electrolyte on an electrolytic cell, in particular a cell for producing aluminum, is such that at least a part of the edge region on the bottom face of the chisel projects out beyond the other regions and is in the form of cutting edges. The bottom face of the chisel features no faces which are inclined outwards and would create outward directed forces as the chisel is forced through the crust.The chisel of the invention allows energy and investment costs to be reduced.
    Type: Grant
    Filed: September 23, 1982
    Date of Patent: November 22, 1983
    Assignee: Swiss Aluminium Ltd.
    Inventors: Thomas Haggenmacher, Edwin Gut, Hans Friedli, Gottfried Maugweiler
  • Patent number: 4414089
    Abstract: Metal is produced in a cell containing a plurality of electrodes which are horizontally disposed and arranged in at least one vertical stack. Each stack includes a cathode, at least one intermediate bipolar electrode and an anode. The electrodes in each stack are arranged in a superimposed, spaced relationship defining inter-electrode spaces between each pair of adjacent electrodes. The upper face of each cathode and of each of the bipolar electrodes has at least one reservoir, bounded by a perimetric wall, for collecting metal produced in the cell. Each perimetric wall has level maintaining means associated therewith so that a pool of the metal in the reservoir will be maintained at a predetermined level beneath the top of the perimetric wall. Metal produced during operation of the cell in excess of that required to fill the reservoir to the predetermined level will drain from the reservoir via the level maintaining means.
    Type: Grant
    Filed: July 30, 1982
    Date of Patent: November 8, 1983
    Assignee: Aluminum Company of America
    Inventors: Matthew J. McMonigle, Alfred F. LaCamera
  • Patent number: 4409083
    Abstract: A cell for the electrolysis of magnesium at low temperatures and electrical potential using a composite anode consisting of a mixture of an oxygen containing compound of magnesium and a reducing agent with internal conductors extending through the composite mixture to provide low resistance current paths through the highly resistive mixture to the active anode surface. The mixture may be employed in a self-baking mode or be prebaked. Alternatively, the mixture may be in particulate form contained within a porous membrane. A bipolar arrangement may also be employed.
    Type: Grant
    Filed: December 22, 1981
    Date of Patent: October 11, 1983
    Assignee: Metallurgical, Inc.
    Inventors: Gary V. Upperman, James C. Withers
  • Patent number: 4405415
    Abstract: In a process for refining Al or Mg a stream of relatively impure molten metal is passed along one face of a grille separator having interstices of the order of 0.1-1 cm in width. The interstices are filled with a molten salt electrolyte adapted to transport ions of the selected metal (Al or Mg) to a body of refined metal on the opposite side of the separator. The relatively impure metal is made in the anode and the refined metal is the cathode. Refined metal is progressively withdrawn from the cathode. The grille separator may be arranged substantially vertical or substantially horizontal, usually with slight inclination. Passages are preferably provided in the separator to allow escape of gas generated at a metal/electrolyte interface.
    Type: Grant
    Filed: October 5, 1981
    Date of Patent: September 20, 1983
    Assignee: Alcan International Limited
    Inventors: Ernest W. Dewing, Adam J. Gesing
  • Patent number: 4402812
    Abstract: The disclosure provides an electrolytic cell sealed in gas-tight and liquid-tight fashion. The cell is comprised of a box-shaped cell tank open at its top and provided with at least one intake duct, at least one overflow duct and at least one discharge duct. A cover is placed on the cell tank and two opposed flanges receiving electrode supporting frames are secured to the inside of the cell tank near the upper end thereof. A chemically resistant and electrically insulating coating is applied to the inside of the cover and cell tank and a plurality of semi-circular recessed grooves spaced apart from each other are formed in the upper rim portion of at least one of the side walls of the cell tank, the recessed grooves receiving semi-circular current beams projecting outwardly.
    Type: Grant
    Filed: March 18, 1982
    Date of Patent: September 6, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Herbert Panter, Hermann Klein, Gerhard Nolte, Eberhard Preisler, Hans-Werner Stephan, Gunter Reichert
  • Patent number: 4401543
    Abstract: An improved electrolytic cell for magnesium chloride which essentially comprises:at least one pairs of anode and cathode arranged with a respective principal face thereof in a substantial verticality,at least one bipolar intermediate electrode placed in a row between the anode and cathode,an electrolytic chamber to contain such electrodes, anda metal collecting chamber which is attached to the electrolytic chamber but separated therefrom by a partition, characterized in that said intermediate electrodes essentially consists of a substantially flat graphite portion to provide an anodic face and an iron portion to provide a cathodic face, both materials being spaced from each other and jointed together with rods of iron, which are tightly secured to the graphite, to ensure an intimate electrical connection therebetween, and that a cavity thus formed between the two materials is arranged to fitly communicate at one end with a through hole in the partition to allow passage of electrolyte bath carrying magnesium m
    Type: Grant
    Filed: November 25, 1981
    Date of Patent: August 30, 1983
    Inventor: Hiroshi Ishizuka
  • Patent number: 4396482
    Abstract: An improved electrolytic cell is provided for production of a metal such as aluminum by electrolysis of a compound of the metal in a solvent or bath such as molten salt. Electrolysis is carried out by passing a current from an anode to a cathode between which the solvent bath is situated. The cathode comprises a base cathode and cathode extension surfaces comprising graphite and at least 90% refractory hard metal such as titanium diboride. The cathode extension surfaces are produced from a mixture comprising at least 90% refractory hard metal and a carbonaceous binder with little or substantially no particulate carbonaceous material and graphitizing said mixture above 2350.degree. C. to graphitize the carbonaceous material therein to exhibit the graphitic structure.
    Type: Grant
    Filed: October 1, 1981
    Date of Patent: August 2, 1983
    Assignee: Aluminum Company of America
    Inventors: Subodh K. Das, Perry A. Foster, Jr., Gregory J. Hildeman
  • Patent number: 4392925
    Abstract: The durability of oxide-ceramic anodes can be increased, if the aluminum surface which lies opposite the active anode surface and is in direct contact with the molten electrolyte, is smaller than the active anode surface. The separated aluminum is collected on the floor of the carbon lining and is sub-divided by an insulating material into pools, which are connected together by means of tubes or channels. The total of all the aluminum surfaces exposed to the melt amounts to 10-90% of the active anode surface.
    Type: Grant
    Filed: April 27, 1981
    Date of Patent: July 12, 1983
    Assignee: Swiss Aluminium Ltd.
    Inventors: Hanspeter Alder, Eugen Schalch
  • Patent number: 4389287
    Abstract: In an electrolysis cell, molten alkali hydroxide is decomposed into products which include alkali metal and water. The water dissolves in the electrolyte where it is decomposed by electrolysis or by reaction with alkali metal thereby reducing efficiency of the cell and yield of the alkali metal.According to the process of the invention, the electrolyte with water dissolved therein is drawn through openings in an anode, is depleted of the dissolved water by a dehydrating means which is separate from the cell, and the dehydrated electrolyte is returned to an anolyte portion of the operating electrolysis cell for further decomposition.According to the apparatus of the invention, the anode comprises a plurality of parallel elongated electrodes which alternate with parallel channels. The electrolyte flows from a return channel, over an electrode, and through a withdrawal channel for the depletion of water and return to operating portions of the electrolysis cell through the return channels.
    Type: Grant
    Filed: January 4, 1982
    Date of Patent: June 21, 1983
    Inventor: Stephen F. Skala
  • Patent number: 4377452
    Abstract: A process and an apparatus is disclosed for controlling the supply of alumina of a cell for the production of aluminum by electrolysis using the Hall-Heroult process wherein each alumina supply orifice of the cell comprises a movable plunger which is electrically insulated from the superstructure of the cell and of which at least the end is electrically conducting and a means for measuring the potential between the end of the movable plunger and a point of the cell which is taken as reference potential. The plunger is moved with an alternating, substantially vertical, upward and downward movement and in each downward movement means detects whether the plunger has come into contact with molten electrolyte or with solidified electrolyte.In the first case, when molten electrolyte is detected the plunger is raised while in the second case when solidified electrolyte is detected the electrical power supplied to the cell is increased in order to remelt the solidified electrolyte.
    Type: Grant
    Filed: May 27, 1981
    Date of Patent: March 22, 1983
    Assignee: Aluminium de Grece
    Inventor: Spyridon Casdas
  • Patent number: 4349231
    Abstract: The invention relates to a chisel alignment unit for a facility for breaking the crust of solidified electrolyte on an electrolytic cell, in particular on a cell for producing aluminum. A mechanically stable alignment box extends from the under side of the chisel in its non-working position to the piston rod. The chisel features at least one vertical alignment surface which is in contact with at least one alignment roll mounted on the alignment box by means of roller bearings. A wiper for removing electrolyte from the chisel is mounted below the alignment rolls and extends over the full width of the alignment surface or surfaces.
    Type: Grant
    Filed: September 5, 1980
    Date of Patent: September 14, 1982
    Assignee: Swiss Aluminium Ltd.
    Inventors: Edwin Gut, Erwin Arnold, Gottfried Maugweiler, Hans Friedli
  • Patent number: 4342637
    Abstract: An anode is provided for use in the electrolytic deposition of aluminum at low temperatures in which the anode is the sole source of aluminum and comprises a composite mixture of an aluminous material such as aluminum oxide and a reducing agent such as carbon. Conductor means of higher electrical conductivity than the anodic mixture are provided to conduct substantially the entire anodic current to the active anode surface thereby reducing the voltage drop through the highly resistive composite mixture. The conductors may be of aluminum and sized to melt back at substantially the same rate at which the mixture is consumed. The mixture may be employed in a self-baking mode or be pre-baked. Alternatively, the mixture may be in a particulate form and contained within a porous membrane which passes the electrolyte or other dissolved material while withholding undissolved impurities. The membrane may be used with a conductor to provide bipolar electrode faces.
    Type: Grant
    Filed: February 6, 1980
    Date of Patent: August 3, 1982
    Assignee: Metallurgical, Inc.
    Inventors: James C. Withers, Gary V. Upperman
  • Patent number: 4338177
    Abstract: A cell for the electrolytic deposition of aluminum at low temperatures and low electrical potential in which the anode is the sole source of aluminum and comprises a composite mixture of an aluminous material such as aluminum oxide and a reducing agent. Conductor means of higher electrical conductivity than the mixture are provided to conduct substantially the entire anodic current to the active anode surface thereby reducing the voltage drop through the highly resistive composite mixture. The mixture may be employed in a self-baking mode or be prebaked. Alternatively, the mixture may be in a particulate form and contained within a porous membrane which passes the electrolyte or other dissolved material while withholding undissolved impurities. The cell may have bipolar electrodes and may be used in combined winning and refining configurations.
    Type: Grant
    Filed: July 30, 1979
    Date of Patent: July 6, 1982
    Assignee: Metallurgical, Inc.
    Inventors: James C. Withers, Gary V. Upperman
  • Patent number: 4332660
    Abstract: The invention relates to a storage bunker for a facility which breaks open the solidified crust on an electrolytic cell. The bunker is subdivided into a large container for alumina and a small container for additives. Below the containers are provided a closing-off plate, a dosing facility and a common outlet pipe leading to the break in the crust. When additives are required, these can be fed directly to the small container via the pipe line for supplying alumina. These are then fed to the cell in measured amounts, if desired, mixed with alumina.
    Type: Grant
    Filed: September 5, 1980
    Date of Patent: June 1, 1982
    Assignee: Swiss Aluminium Ltd.
    Inventors: Hans Friedli, Erwin Arnold
  • Patent number: 4328085
    Abstract: The invention relates to a device for point feeding an electrolytic cell, in particular a cell for producing aluminum. A point feeder unit comprising a raw materials feeding device and a crust breaking facility releasably mounted on a storage bunker is mounted on a beam, can be freely displaced along and/or across the cell and can be removed in the vertical direction with a crane.
    Type: Grant
    Filed: September 5, 1980
    Date of Patent: May 4, 1982
    Assignee: Swiss Aluminium Ltd.
    Inventors: Hans Friedli, Edwin Gut, Peter Aeschbach
  • Patent number: 4321115
    Abstract: A device for feeding measured amounts of alumina to the break in the crust on an electrolytic cell is such that in a stationary channel there is a transporting facility which is connected to a power drive facility and to an alumina silo. The channel is a feed pipe for a piston arrangement which is situated under an inlet opening from the silo and features at least one opening or chamber as a space for a limited amount of alumina to be fed to the cell. This space is delimited by a blocking piston and a feed piston. The width of this space can however be varied and, if desired, can correspond to the width of the inlet opening and an outlet opening which is laterally displaced with respect to the inlet.If more feeding chambers are desired, these are formed by a plurality of blocking pistons and feeding pistons. The piston arrangement is connected via rods to a, preferably pneumatic, power drive and can be moved back and forwards.
    Type: Grant
    Filed: February 25, 1980
    Date of Patent: March 23, 1982
    Assignee: Swiss Aluminium Ltd.
    Inventors: Hans J. Rebmann, Theo Mueller
  • Patent number: 4308116
    Abstract: Magnesium is electrolytically produced from a salt melt comprising magnesium chloride by the use of an electrolyzer having at least one electrolysis compartment and at least one metal separating compartment separated from the electrolysis compartment by a partition wall. Magnesium chloride is fed in solid form in a direction counter current to the flow of chlorine gas liberated during electrolysis to a melting room or chamber in the electrolysis compartment arranged such that contact between the magnesium chloride and the anodes of the electrolyzer is avoided. Flow patterns are produced in the melt to ensure that sludge forming impurities in the fed magnesium chloride are continuously removed from the electrolysis compartment to the metal separating compartment.
    Type: Grant
    Filed: June 16, 1980
    Date of Patent: December 29, 1981
    Assignee: Norsk Hydro a.s.
    Inventors: Knut A. Andreassen, Oystein Boyum, Henry K. Johnsen, Leiv B. Ognedal, Peder R. Solheim
  • Patent number: 4305671
    Abstract: An apparatus for agitating the contents of an electrolytic sodium cell receiver, which apparatus comprises(a) an agitator having a blade portion and a shank portion, the blade portion being fitted within the receiver housing and having three blades extending horizontally and laterally and spaced at about 120.degree. intervals, and the shank portion extending upward out of the receiver housing, and(b) means for imparting reciprocating rotary motion to the agitator.
    Type: Grant
    Filed: January 14, 1980
    Date of Patent: December 15, 1981
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Francis J. Ross
  • Patent number: 4302302
    Abstract: A method of feeding alumina to a Soderberg type aluminium electrolytic cell characterized by forming a box body having an opening in the upper part and an opened lower end on the side of the anode of said electrolytic cell with an anode casing, a dam plate located outside said cathode casing and above a freeze of said electrolytic cell and two side plates covering spaces between said anode casing and said dam plate, charging alumina from said opening so that said alumina is stored in said box body and simultaneously flows out from the lower end of said dam plate to accumulate on said freeze, forming a slope in response to its angle of repose, and thereby, when said freeze is broken, the accumulated alumina is charged into the electrolytic bath of said electrolytic cell and simultaneously the alumina stored in said box body flows out spontaneously to form a new slope of accumulated alumina, and an apparatus for the same.
    Type: Grant
    Filed: May 9, 1980
    Date of Patent: November 24, 1981
    Assignee: Mitsubishi Light Metal Ind., Ltd.
    Inventor: Toshiaki Kaifuchi
  • Patent number: 4276145
    Abstract: A Castner type electrolysis cell, operating to produce alkali metal from molten alkali hydroxide, forms water at its anode which dissolves in surrounding anolyte. Normally, the water is itself electrolyzed and consumes as much electrical current at the Castner cell operating voltage as does production of the alkali metal. Since water has substantially lower decompositon voltage than alkali metal, electrolysis of water in the Castner cell represents unrecoverable energy loss.This invention improves energy efficiency of alkali hydroxide electrolysis by electrolyzing the formed water at a lower voltage to produce hydrogen and oxygen and by reacting the hydrogen and oxygen electrochemically to recover a portion of the electrical energy used for the electrolysis of water. An anolyte electrolytic dehydrator, which is a cell designed for electrolysis of water in molten alkali hydroxide, receives anolyte from the Castner cell and dehydrates the anolyte by electrolysis for return to the Castner cell.
    Type: Grant
    Filed: January 31, 1980
    Date of Patent: June 30, 1981
    Inventor: Stephen F. Skala
  • Patent number: 4265726
    Abstract: To prevent transport of deleterious oxygen and moisture to liquid electrolyte in an aluminum electroplating vessel, workpieces move towards the vessel through an antechamber containing inert gas under pressure and comprising a plenum chamber opening downwardly into a lock chamber containing aprotic liquid. They move down into the liquid, then up out of it, into and through an inverted-U-shaped passageway containing higher pressure inert gas and which communicates with the lock chamber below the surface of the liquid therein and communicates with the electrolysis vessel above the surface of the electrolyte. At each connection between parts, where atmospheric oxygen might move towards the electrolyte, there are double mechanical seals defining a substantially annular chamber filled with aprotic liquid that forms a gas barrier, and such liquid is, where possible, shielded by inert gas.
    Type: Grant
    Filed: January 7, 1980
    Date of Patent: May 5, 1981
    Assignee: Montblanc-Simplo GmbH
    Inventors: Gunther Herrnring, Klaus P. Nussen
  • Patent number: 4257855
    Abstract: An electrolytic cell for the production of aluminum metal comprises a permanent hollow anode structure of substantially corrosion-resistant material, with numerous perforations in the base of said structure, a packed bed of consumable carbon pieces supported by said base within the hollow space of said structure, means for heating said base so as to form a molten cryolite bath upon cell start-up, means for controllably cooling the walls of said anode structure to form a protective layer of frozen cryolite over said walls at the air-cryolite interfaces, means for adding fresh pieces of said consumable carbon to replenish said packed bed when a substantial portion thereof has been consumed, and means for adjusting the depth of immersion of said packed bed within said molten cryolite bath so as to reduce voltage and energy requirements or increase the rate of aluminum production.
    Type: Grant
    Filed: July 14, 1978
    Date of Patent: March 24, 1981
    Inventor: Solomon Zaromb
  • Patent number: 4219401
    Abstract: Feed cathode for an electrolytic cell with a feed conduit suited to pass a metal compound therethrough from a source to an electrolyte in the cell. The feed cathode includes a member surrounding and substantially entirely enclosing at least an outlet of the conduit. The member is at least partially formed of an electrically conductive foraminous body suited to pass the electrolyte and ions of a multivalent metal compound therethrough. Preferably, the foraminous body has an electrical coefficient of greater than zero to about 1 and a flow coefficient of from about 0.1 to about 300.
    Type: Grant
    Filed: August 7, 1978
    Date of Patent: August 26, 1980
    Assignee: The D-H Titanium Company
    Inventor: David R. Johnson
  • Patent number: 4210513
    Abstract: A pneumatic anode positioning apparatus is disclosed for positioning any number of a plurality of anodes relative to a cathode in an electrolytic cell. This apparatus comprises a means for determining the desired anode position for each of the anodes and converting the amount of movement necessary to attain such position to a number of increments of predetermined displacement.
    Type: Grant
    Filed: November 2, 1978
    Date of Patent: July 1, 1980
    Assignee: Aluminum Company of America
    Inventors: Thomas A. Mutschler, Gary J. Zimmerman
  • Patent number: 4198282
    Abstract: A replaceable cathode unit, suitable as a module for the building up of stable, non-deformable cathode systems in electrolyzers for the production of magnesium by melted salt electrolysis, is the form of a straight, longitudinal main cathode with active cathode side surfaces and two shorter transverse cathodes arranged approximately at right angles in relation to the main cathode. One transverse cathode is at the front end of the main cathode, and the other transverse cathode is at the back end of the main cathode.
    Type: Grant
    Filed: May 22, 1978
    Date of Patent: April 15, 1980
    Assignee: Norsk Hydro A.S
    Inventors: Knut A. Andreassen, Henry K. Johnsen, Peder R. Solheim, Sigbjorn Kleveland
  • Patent number: 4179346
    Abstract: Metal such as aluminum is produced electrolytically from metal chlorides or other halides dissolved in a molten solvent bath of higher decomposition potential in a cell including one or more carbonaceous or graphite cathode surfaces spaced from opposed anodes, particularly a bipolar cell, with bath flow through the spaces between the anodes and cathodes. The wetting characteristics of the graphite cathode with respect to the metal deposited there by electrolysis are selectively balanced with the bath flow over the cathode and with the anode-to-cathode distance. Cathode surface wear rate is substantially reduced if the surface is wettable by the metal in regions of low bath flow velocity or regions of greater anode-cathode distance. The wear rate is also reduced by using a non-wettable cathode surface in regions of higher bath flow velocity or regions of closer anode-cathode distance.
    Type: Grant
    Filed: February 26, 1979
    Date of Patent: December 18, 1979
    Assignee: Aluminum Company of America
    Inventors: Subodh K. Das, Paul J. Boget
  • Patent number: 4172018
    Abstract: A process and electrolytic cell are described for the production of aluminum whereby the feeding of the cell with fresh alumina, including the breaking of the crust of solidified electrolyte, is carried out in at least one space running transverse to the longitudinal axis of the cell.
    Type: Grant
    Filed: June 19, 1978
    Date of Patent: October 23, 1979
    Assignee: Swiss Aluminium Ltd.
    Inventors: Hermann Moix, Alfred Sturm
  • Patent number: 4154661
    Abstract: An electrolytic cell in which a terminal cathode and a bipolar electrode located immediately adjacent the cathode are spaced apart a distance greater than the height at which molten metal produced on the cathode will accumulate before the metal begins to run off the cathode. In this manner, shorting together of the cathode and the adjacent bipolar electrode by the accumulation of molten metal is avoided under both operating and standby conditions. Under standby conditions, using the heat produced by the resistance of the anode and cathode of the cell to the flow of electrical current directed therethrough, metal tends to accumulate on at least a portion of the cathode because of a potential (voltage) difference existing between a portion of the anode and a portion of the cathode.
    Type: Grant
    Filed: May 26, 1978
    Date of Patent: May 15, 1979
    Assignee: Aluminum Company of America
    Inventors: Wayne W. Hyland, Robert F. Robl, Jr., Alfred F. LaCamera
  • Patent number: 4148706
    Abstract: An apparatus for filling an anode paste in an anode hole formed when an anode contact stud is pulled out from the anode of a vertical Soderberg aluminum electrolytic cell comprises horizontally moveable anode paste charging arm with an anode paste conveying means and a hopper for storing the anode paste and feeding the paste to the anode paste charging arm when required, the arm and the hopper being provided at a support movable along the electrolytic cell.
    Type: Grant
    Filed: February 2, 1978
    Date of Patent: April 10, 1979
    Assignee: Sumitomo Aluminium Smelting Co., Ltd.
    Inventors: Tadaaki Ohiwa, Yosio Kawase
  • Patent number: 4126525
    Abstract: In a method of continuously feeding alumina to an aluminum electrolytic cell in which aluminum is prepared by the electrolysis of alumina, the feed of alumina is controlled by starting it when occurrence of an anode effect is detected or anticipated, and the feed is switched between high speed, low speed and interruption during each one of a series of cycles of operation.
    Type: Grant
    Filed: September 1, 1977
    Date of Patent: November 21, 1978
    Assignee: Mitsubishi Keikinzoku Kogyo Kabushiki Kaisha
    Inventors: Kiyoaki Wakaizumi, Toshiki Matsunaga, Yuji Mino
  • Patent number: 4119505
    Abstract: The invention relates to a process and apparatus for ridding the worn anode butts of electrolysis bath crusts which adhere to them.The apparatus essentially comprises a jack supporting a pneumatic drill equipped with a percussion tool. The jack is supported by a movable and orientatable arm.Application to the recovery of worn anodes from igneous electrolysis cells for the manufacture of aluminium.
    Type: Grant
    Filed: April 6, 1977
    Date of Patent: October 10, 1978
    Assignee: Aluminium Pechiney
    Inventors: Pierre Baillot, Pierre Berthet
  • Patent number: 4119504
    Abstract: A method of preventing the conduction of electricity along a film of molten salt on a surface. An electrically insulating material which is not wet by the molten salt is interposed in the film. The material is in the form of a protrusion on the surface.
    Type: Grant
    Filed: May 17, 1977
    Date of Patent: October 10, 1978
    Assignee: Aluminum Company of America
    Inventor: Robert L. Hargis
  • Patent number: 4118304
    Abstract: In an electrolytic alumina reduction cell having a cathode formed by carbon blocks at the bottom and a side wall made of carbon substrate, a heat insulating substrate is interposed at the boundary between the cathode at the bottom and the side wall so as to prevent heat transfer from the bottom to the side wall. The stable solid bath is formed on the inner side wall of the electrolytic cell whereby the heat radiation from the electrolytic cell can be reduced and the heat energy can be saved.
    Type: Grant
    Filed: August 16, 1977
    Date of Patent: October 3, 1978
    Assignee: Mitsubishi Light Metal Industries Limited
    Inventor: Youji Arita
  • Patent number: 4113584
    Abstract: Feed cathode for an electrolytic cell with a feed conduit suited to pass a metal compound therethrough from a source to an electrolyte in the cell. The feed cathode includes a member surrounding and substantially entirely enclosing at least an outlet of the conduit. The member is at least partially formed of an electrically conductive foraminous body suited to pass the electrolyte and ions of a multivalent metal compound therethrough. Preferably, the foraminous body has an electrical coefficient of greater than zero to about 1 and a flow coefficient of from about 0.1 to about 300.
    Type: Grant
    Filed: September 13, 1976
    Date of Patent: September 12, 1978
    Assignee: The Dow Chemical Company
    Inventor: David R. Johnson
  • Patent number: 4092228
    Abstract: The operating characteristics of a Downs-type electrolytic cell are improved by incorporating a sealed weir between the riser/cooler and the molten metal receiver and by providing means for venting inert gas from the receiver through the vapor space of the riser/cooler.
    Type: Grant
    Filed: March 7, 1977
    Date of Patent: May 30, 1978
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Francis Joseph Ross
  • Patent number: 4089769
    Abstract: The invention is for placement in a molten salt electrolysis cell and a jacket means on the cell for providing a chamber for containment of a coolant. The cell and the jacket means have an orifice extending from the exterior of the jacket means into the interior of the cell. The invention, a tapping apparatus, includes a tapping tube in the orifice extending into the interior of the cell, and a packing tube and packing in the orifice and surrounding the tapping tube, with the improvement including the extending of the packing tube and packing past the jacket means.
    Type: Grant
    Filed: May 17, 1977
    Date of Patent: May 16, 1978
    Assignee: Aluminum Company of America
    Inventor: Charles E. Jennings
  • Patent number: 4089770
    Abstract: An electrolytic cell for the electrochemical separation of selected metals from electrodissociatable compounds thereof in the molten state utilizing as electrode separator a plurality of solid electrolyte tubes which, under the influence of an electrical potential, are permeable to the flow of selected cations, but impermeable to fluids and the flow of anions and other cations.
    Type: Grant
    Filed: July 11, 1977
    Date of Patent: May 16, 1978
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Charles H. Lemke
  • Patent number: 4081335
    Abstract: A process of electro-plating elongate articles of passive metal with a thin, homogeneous coating of a noble metal. The article is passed through an electrolyte bath comprising a salt melt of alkali metals or alkaline earth metals containing a cyano radical. The articles are guided through the bath by guides of a material selected from oxides of aluminum, silicon, yttrium, or zirconium; nitrides of silicon, borium, or titanium; or carbides of silicon or titanium. The entire process is carried out in an inert atmosphere.
    Type: Grant
    Filed: October 20, 1975
    Date of Patent: March 28, 1978
    Inventors: Friedrich Von Stutterheim, Jorg Wurm
  • Patent number: 4076602
    Abstract: A method of producing magnesium and chlorine including the steps of injecting concentrated magnesium chloride containing brine into a hot gas spray drier wherein most of the water is evaporated to produce cell feed in the form of a powder of high porosity discrete particles of impure MgCl.sub.2, the impure particles being purified by in situ reaction within an electrolytic cell by depositing the particles onto an area of the surface of molten electrolyte whereby a portion of the entrained impurities are vaporized and withdrawn and circulating the electrolyte through the interelectrode space where the remaining impurities are chlorinated by chlorine gas produced at the anode, the circulation being at a rate to entrain most of the magnesium oxide particles in suspension for reaction with chlorine gas generated at the anode element. The molten magnesium produced at the cathode is withdrawn in the usual manner.
    Type: Grant
    Filed: April 14, 1975
    Date of Patent: February 28, 1978
    Inventor: Roger M. Wheeler
  • Patent number: 4058448
    Abstract: The electrolyzer has a refractory-lined hollow shell divided into a group of electrolytic cells and a magnesium collecting cell by a vertical separator plate that is shorter than the shell. Steel cathodes shaped as frames embrace a graphite anodes arranged in groups. To convey magnesium from the electrolytic cells into a magnesium collecting cell, at least two passageways are provided, each of them being substantially at right angles to the graphite anodes and to the separator plate. The separator plate has through perforations situated below the electrolyte level. Each of the passageways is confined between the wall of the electrolyzer shell and the portion of the cathode that faces towards the magnesium collecting cell. The width of each of the magnesium conveyance passageways is a maximum of three times the width of the gap across the adjacent graphite anode and steel cathode in each electrolytic cell.
    Type: Grant
    Filed: June 23, 1976
    Date of Patent: November 15, 1977
    Inventors: Konstantin Dmitrievich Muzhzhavlev, Sergei Petrovich Kosarev, Vladimir Ivanovich Schegolev, Andrei Borisovich Ivanov, Oleg Nikolaevich Romanenko, Vladimir Dmitrievich Yazev, Alexei Vasilievich Vasiliev
  • Patent number: 4053384
    Abstract: Mechanism for changing anode blocks in electric furnaces for making aluminum and performing related tasks including charging the furnaces with alumina is disclosed. The mechanism includes a rotatable operator's cab carrying remotely controlled tools and alumina charging reservoirs. Both the cab and the reservoirs are translatable on the main support so as to align properly with any furnace of plural rows of furnaces.
    Type: Grant
    Filed: October 10, 1975
    Date of Patent: October 11, 1977
    Inventor: Frederik W. Siegmund
  • Patent number: 4053383
    Abstract: Apparatus for electrodepositing aluminum in which an electroplating trough, which contains aprotic oxygen-free and water-free organo-aluminum electrolyte, is closed off in an airtight manner and is accessible only via a lock chamber disposed thereabove and which uses, for inserting and removing the work pieces, a detachable coupling rod carrying a frame with the articles to be electroplated permitting a strongly adhering aluminum layer to be deposited onto work pieces of any design desired with the exclusion of air.
    Type: Grant
    Filed: August 12, 1976
    Date of Patent: October 11, 1977
    Assignee: Siemens Aktiengesellschaft
    Inventors: Richard Dotzer, Klaus Stoger, Josef Stadter
  • Patent number: 4049529
    Abstract: An apparatus is arranged over the bath of an electrolytic furnace containing molten aluminium.The apparatus has beams with tools which can be raised and lowered in a reciprocal manner to break-up the crust which forms on the top of the molten aluminium. Reservoirs containing alumina are also carried by the beams and serve to selectively charge quantities of alumina into the bath. Probes or lances are extendible and retractible in relation to the beams and serve to inject air into the molten aluminium.
    Type: Grant
    Filed: July 9, 1976
    Date of Patent: September 20, 1977
    Assignee: Gewerkschaft Eisenhutte Westfalia
    Inventor: Franz Golla
  • Patent number: RE30330
    Abstract: A process for purifying aluminum alloys comprises providing molten aluminum alloy in a container having a porous wall therein capable of containing molten aluminum in the container and being permeable by the molten electrolyte. Aluminum is electrolytically transported through the porous wall to a cathode thereby substantially separating the aluminum from alloying constituents.
    Type: Grant
    Filed: May 17, 1979
    Date of Patent: July 8, 1980
    Assignee: Aluminum Company of America
    Inventors: Subodh K. Das, C. Norman Cochran, Richard A. Milito, Robert M. Mazgaj, Walter W. Hill