With Feeding And/or Withdrawal Means Patents (Class 204/245)
  • Patent number: 6372099
    Abstract: A cell for the electrowinning of aluminium comprising one or more anodes, each having a metal-based anode substrate, comprising a metal core covered with an metal layer, an oxygen barrier layer, one or more intermediate layers and an iron layer. The anode substrate is covered with an electrochemically active iron oxide-based outside layer, particularly a hematite-based layer, which remains dimensionally stable during operation in a cell by maintaining in the electrolyte a sufficient concentration of iron species. The cell operating temperature is sufficiently low so the required concentration of iron species in the electrolyte is limited by the reduced solubility of iron species in the electrolyte at the operating temperature, limiting the contamination of the product aluminium by iron to an acceptable level. The iron oxide-based layer is an applied coating or an oxidised surface of a substrate, the surface of which contains iron.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: April 16, 2002
    Assignee: Moltech Invent S.A.
    Inventors: Jean-Jacques Duruz, Vittorio de Nora
  • Patent number: 6368736
    Abstract: A reactant product valve for an electrolysis cell. The valve comprises first and second members disposed generally horizontally in the reactant product above the electrodes. The second member floats on liquid reactant product, sinks in liquid reactant and is movable between a closed position and open positions to control flow of reactant product through the valve. A plurality of apertures in the second member are offset horizontally from a plurality of apertures in the first member. The valve has at least one open position at which the second member is spaced from the first member so that the apertures in the first member communicate with the apertures in the second member, thereby allowing movement of reactant product through the valve. In the closed position the second member is adjacent the first member and the apertures do not communicate, thereby prohibiting movement of reactant product through the valve.
    Type: Grant
    Filed: July 23, 2000
    Date of Patent: April 9, 2002
    Inventor: Wayne Thomas Bliesner
  • Patent number: 6365018
    Abstract: A non-carbon, metal-based, high temperature resistant, electrically conductive and electrochemically active anode of an aluminum production cell has a metal-based substrate having an adherent coating applied prior to its immersion into the electrolyte and start up of the electrolysis. The coating is obtainable from one or more layers applied from: a liquid solution, a dispersion or suspension in a liquid or a paste, a pasty or non-pasty slurry, and combinations thereof with or without one or more further applied layers, with or without heat treatment between two consecutively applied layers when at least two layers are applied.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: April 2, 2002
    Assignee: Moltech Invent S.A.
    Inventor: Vittorio de Nora
  • Patent number: 6358393
    Abstract: A cell for the production of aluminium by the electrolysis of an aluminium compound dissolved in a molten electrolyte, in which an outer mechanical structure forming an outer shell (21) houses therein one or more inner electrically-conductive cathode holder shells or plates (31) which contain a cathode mass (32) and is/are connected electrically to the busbar. The cathode mass (32) has an aluminium-wettable top surface (37), preferably at a slope forming a drained cathode. The inner cathode holder shell or shells (31) is/are separated from the outer shell (21) by an electric and thermic insulation (40), the cathode holder shell(s) (31) also serving to distribute current uniformly to the cathode mass (32). The or each cathode (30) formed by the cathode holder shell (31) and cathode mass (32) is removable from the cell as a unit.
    Type: Grant
    Filed: March 30, 2000
    Date of Patent: March 19, 2002
    Assignee: Moltech Invent S.A.
    Inventors: Georges Berclaz, Vittorio de Nora
  • Publication number: 20020027069
    Abstract: A cell for the electrowinning of aluminum comprises at least one non-carbon metal-based anode (10) having an electrically conductive metallic structure (12, 13, 15) which is suspended substantially parallel to a facing cathode (20, 21, 22). Such metallic structure (12, 13, 15) comprises a series of parallel horizontal anode members (15), each having an electrochemically active surface (16) on which during electrolysis oxygen is anodically evolved. The electrochemically active surfaces (16) are in a generally coplanar arrangement to form the active anode surface. The anode members are spaced apart from one another by inter-member gaps forming flow-through openings (17) for the circulation of electrolyte (30) driven by the escape of anodically-evolved oxygen. The electrolyte (30) may circulate upwardly and/or downwardly in the flow-through openings (17) and possibly around the anode structure (12, 13, 15).
    Type: Application
    Filed: July 2, 2001
    Publication date: March 7, 2002
    Inventor: Vittorio de Nora
  • 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: 6319388
    Abstract: This method of managing the operation of a plant for the production of aluminium by igneous electrolysis, of the type having a set (2, 3) of two electrolysis tankrooms, each having a series of tanks, the tankrooms being mutually parallel and symmetrical with respect to a central passageway (4) in which the handling of the liquid-aluminium tapping ladle is carried out, consists in carrying out the various handling operations at each of the tanks, necessary for the operation of the plant, in a closed loop, the members (13, 13′, 13″, 13′″, 14, 14′, 14″, 14′″) needed for the operation being moved over all the tanks of the two tankrooms of continuous cycles. The invention also relates to the plant for implementing this method.
    Type: Grant
    Filed: December 7, 1999
    Date of Patent: November 20, 2001
    Assignee: ACIS
    Inventors: GĂ©rard Piron, Serge Huon
  • Patent number: 6306279
    Abstract: A device for adjusting the distance between the anode and the cathode of an electrolytic cell having a compartment, at least one anode partially disposed in a molten metal producing salt bath and a layer of molten metal above a cathode. The device includes a displacement device partially disposed within the layer of molten metal, and an actuator to move the displacement device generally vertically.
    Type: Grant
    Filed: April 7, 2000
    Date of Patent: October 23, 2001
    Assignee: Alcoa Inc.
    Inventor: Robert L. Kozarek
  • Publication number: 20010020590
    Abstract: A cell for the electrowinning of aluminium comprising one or more anodes (10), each having a metal-based anode substrate, for instance comprising a metal core (11) covered with an metal layer 12, an oxygen barrier layer (13), one or more intermediate layers (14; 14A, 14B) and an iron layer (15). The anode substrate is covered with an electrochemically active transition metal oxide layer, in particular an iron oxide-based outside layer (16) such as a hematite-based layer, which remains dimensionally stable during operation in a cell by maintaining in the electrolyte a sufficient concentration of iron species and dissolved alumina. The cell operating temperature is sufficiently low so species and dissolved alumina.
    Type: Application
    Filed: January 29, 2001
    Publication date: September 13, 2001
    Inventors: Jean-Jacques Duruz, Vittorio de Nora, Olivier Crottaz
  • Publication number: 20010017260
    Abstract: An apparatus for electrolytic production of magnesium includes a plurality of upright anode elements interspread with a plurality of cathode elements situated within at least one electrolysis compartment. At least one section, defined between two adjacent anodes and having an elongated loading inlet, is provided for receiving and melting of a substantially solid raw material. A gas discharging outlet is formed for discharging of chlorine gas developed at the plurality of anodes. A baffle is supported by the receiving anodes in the vicinity of the gas discharging outlet. The baffle prevents direct flow of a mixture of chlorine gas and fine dust particles resulted from loading of the solid raw material between the section and gas discharging outlet.
    Type: Application
    Filed: December 19, 2000
    Publication date: August 30, 2001
    Applicant: State Institute
    Inventors: Igor V. Zabelin, Georgy M. Shehovtsov, Vladimir N. Deviatkin, Irina L. Sikorskaya, Alexander M. Tatakin, Tatiana V. Zabelina
  • Patent number: 6258246
    Abstract: A drained cathode cell for the electrowinning of aluminium comprises a cell bottom (20) arranged to collect product aluminium and thermic insulating sidewalls (40) lined with a molten electrolyte resistant sidewall lining (50), in particular containing silicon carbide, silicon nitride or boron nitride. The thermic insulating sidewalls (40) inhibit formation of an electrolyte crust on the lining (50), whereby the lining (50) is exposed to molten electrolyte. The cell bottom (20) has a peripheral zone from which the insulating sidewalls (40) extend generally vertically to form, with the cell bottom, a trough for containing molten electrolyte and aluminium produced on at least one drained cathode (32). The peripheral zone of the cell bottom (20) is arranged to keep the product aluminium from contacting and reacting with the molten electrolyte resistant sidewall lining 50).
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: July 10, 2001
    Assignee: Moltech Invent S.A.
    Inventors: Jean-Jacques Duruz, Vittorio de Nora, Georges Berclaz
  • 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: 6197176
    Abstract: An apparatus for promoting reactions between particles suspended in a liquid is provided. The apparatus includes a treatment cell having an electrode array. The suspension of the particles is fed to the treatment cell by feeding means. The liquid is removed from the treatment cell by removing means. The feeding means is connected to the electrode array in the cell and adapted to generate a first non-uniform electrical field, at a first frequency, within the cell. The removing means is connected to the electrode array in the cell and adapted to generate, within the cell, a second non-uniform electrical field, at a second frequency which is different from the first frequency. The apparatus further includes means for simultaneously applying at least the first non-uniform electrical field, at the first frequency, and the second non-uniform electrical field, at the second frequency.
    Type: Grant
    Filed: May 15, 1998
    Date of Patent: March 6, 2001
    Assignee: BTG International Limited
    Inventors: Ronald Pethig, Julian Burt
  • Patent number: 6153066
    Abstract: The invention relates to a tool holder module intended to be used in lifting gear, characterized in that it is equipped with two independently motorized lifting member:a first member, which consists of a lifting system with cable(s) wrapped over electrically motorized drum(s) and returned at a sheaving system, said first member being intended to displace a load at a relatively high speed and over a relatively large distance;a second member, one of the constituent elements of which is secured to the end of the cable or cables of said first member after return at the sheaving system and is intended, in cooperation with this system, to displace a heavier load vertically at a lower speed and over a limited distance.
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: November 28, 2000
    Inventor: Gerard Piron
  • 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: 6093304
    Abstract: An electrolytic cell for the electrowinning of aluminium from alumina dissolved in a halide-containing molten electrolyte, has a cathode cell bottom made of a series of carbon cathode blocks (10) connected side-by-side by glue or ramming paste, each one provided with steel or other conductive bars (11) for the delivery of current and a series of anodes (15) facing the cathode cell bottom. The tops of the carbon blocks (10) forming the cathode cell bottom are shaped in such a way as to provide in the cell bottom a series of parallel channels (25) or grooves preferably coated with an aluminium-wettable refractory coating (35) covered in use by a pool (40) of molten aluminium or a layer of molten aluminium forming a drained surface. Movement of the aluminium pool (40) is decreased, cell operation improved and cell life extended.
    Type: Grant
    Filed: March 29, 1999
    Date of Patent: July 25, 2000
    Assignee: Moltech Invent S.A.
    Inventor: Vittorio de Nora
  • Patent number: 6090264
    Abstract: A tool holder module intended to be used in lifting gear, characterized in that it is equipped with two independently motorized lifting member: a first member, which consists of a lifting system with cable(s) wrapped over electrically motorized drum(s) and returned at a sheaving system, the first member being intended to displace a load at a relatively high speed and over a relatively large distance; a second member, one of the constituent elements of which is secured to the end of the cable or cables of the first member after return at the sheaving system and is intended, in cooperation with this system, to displace a heavier load vertically at a lower speed and over a limited distance.
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: July 18, 2000
    Inventor: Gerard Piron
  • 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: 6024847
    Abstract: Described is a method and apparatus for producing high purity titanium and high purity titanium so produced. The process contemplates producing titanium sponge in a container and performing titanium fused salt electrolysis in situ in the same container to produce high purity titanium crystal, and where especially low oxygen content is desired, to treat the high purity titanium crystal as produced with iodine.
    Type: Grant
    Filed: February 2, 1998
    Date of Patent: February 15, 2000
    Assignee: The Alta Group, Inc.
    Inventors: Harry Rosenberg, Nigel Winters, Yun Xu
  • Patent number: 5961812
    Abstract: A process for changing spent anodes while recovering the majority of the gaseous compounds evolved by the spent anodes and by the bath crust removed from the electrolytic pots during the cooling phase uses an effluent-collection device for electrolytic pots. A device for collecting gaseous effluents from pots for the production of aluminum by igneous electrolysis allows the recovery of the gaseous compounds evolved by the spent anodes and by the crust which they contain during the replacement and cooling of these anodes and this crust. The device preferably includes a degassing and cooling container located at one of the ends of the hooding device of the pots. The container can be made to communicate with the suction produced by the gas collection device.
    Type: Grant
    Filed: October 23, 1997
    Date of Patent: October 5, 1999
    Assignee: Aluminium Pechiney
    Inventors: Gilbert Bouzat, Pierre Personnet
  • Patent number: 5956842
    Abstract: An apparatus for breaking the anode butt (15) and stripping the thimbles (13) from the yoke stubs (12) of an anode. The apparatus includes a support frame (20), a fixed plate assembly (21) secured to the supporting frame (20) and a ram assembly (22) extendible towards the fixed plate assembly (21). The fixed plate assembly (21) comprises a substantially rigid fixed plate (23) having recesses (24a) to receive the yoke (11) and yoke stubs (12). The recesses (24a) are shaped such that the thimbles (13) on the yoke stubs (12) of the anode butt (15) abut against the fixed plate assembly (21) during the extension of the ram assembly (22) to contact and break the anode butt. The fixed plate assembly (21) may be provided with a stub locating mechanism which locates the stubs in position and abuts against the thimbles (13) on the stubs (12) during the extension of the ram assembly (22). The stub locating mechanism also abuts against and is supported by the substantially rigid fixed plate (23).
    Type: Grant
    Filed: October 31, 1997
    Date of Patent: September 28, 1999
    Assignee: Comalco Aluminium Limited
    Inventor: Karl Stewart
  • Patent number: 5948963
    Abstract: Disclosed is a gas sensor comprising a sensor element for measuring a predetermined gas component contained in an introduced measurement gas, and a protective cover arranged to surround a forward end of the sensor element; the gas sensor including the sensor element having a gas-introducing port which is disposed at a forward end surface thereof for introducing the measurement gas thereinto; and the protective cover comprising an inner protective cover and an outer protective cover. The inner protective cover is provided with an opening section which makes communication with the gas-introducing port. An inner protective cover space, which is formed between the inner protective cover and the sensor element, is isolated from a communication passage which makes communication from the opening section of the inner protective cover to the gas-introducing port of the sensor element so that the measurement gas principally diffuses and flows from the opening section into the gas-introducing port of the sensor element.
    Type: Grant
    Filed: May 15, 1998
    Date of Patent: September 7, 1999
    Assignee: NGK Insulators, Ltd.
    Inventors: Nobuhide Kato, Nobukazu Ikoma, Yasuhiko Hamada
  • Patent number: 5928489
    Abstract: A low temperature method and apparatus for removing halides from relatively low temperature gas mixtures (below about 150.degree. C.) using an electrochemical cell provided with inert electrodes and an electrolyte which will provide anions compatible with the halide anions formed at the anode. The electrolyte is elected to provide inert stable cations at the temperatures encountered. The gas mixture is passed by the cathode where the halides are converted to X.sup.-. The anions migrate to the anode where they are converted to a stable gaseous form at much greater concentration levels. Current flow may be effected by utilizing an external source of electrical energy or by passing a reducing gas such as hydrogen past the anode.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: July 27, 1999
    Assignee: Georgia Tech Research Corp.
    Inventor: Jack Winnick
  • Patent number: 5914023
    Abstract: An actuator assembly comprises a piston within an actuating cylinder, and a valve for controlling the flow of actuating fluid to the first side of the piston. When the valve is actuated the flow of fluid to the first side of the piston is stopped and the pressure of the actuating fluid on the piston is sufficient to maintain the piston in a predetermined position along the stroke path. Also disclosed is a method of actuating the crust breaker of a smelter pot using the apparatus described. Fluid leakage through the piston rod sealing assembly is reduced; the volume of compressed air used by the smelter is reduced; and the working life of the actuator is improved.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: June 22, 1999
    Assignees: Terry Fluid Controls Pty Ltd, Comalco Aluminium Limited
    Inventors: Ronald Keith Roy, Peter Jones
  • Patent number: 5914440
    Abstract: The present invention is concerned with a system for the filtration of molten material. The system is particularly useful for removing MgO impurities present in molten magnesium chloride electrolyte. The invention also comprises a method for removing solid particles from molten materials. Preferred molten materials include magnesium, aluminum, magnesium chloride electrolyte and aluminum electrolyte. The concentration of solid remaining in the molten material is less than 0.05 wt %.
    Type: Grant
    Filed: March 18, 1997
    Date of Patent: June 22, 1999
    Assignee: Noranda Inc.
    Inventors: Cesur Celik, Pasquale Ficara, Daniel Laroche
  • Patent number: 5904821
    Abstract: An electrolytic cell is provided that increases current efficiency in the fused alkali chloride salt electrolysis process for producing chlorine and sodium or lithium by improved design of the cell's product collector, diaphragm and graphite anode.
    Type: Grant
    Filed: July 25, 1997
    Date of Patent: May 18, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Howard M. Blank, Oswald Robert Bergmann, Walter John Simmons
  • Patent number: 5888360
    Abstract: An electrolytic cell for the electrowinning of aluminum from alumina dissolved in a halide-containing molten electrolyte, has a cathode cell bottom made of a series of carbon cathode blocks (10) connected side-by-side by glue or ramming paste, each one provided with steel or other conductive bars (11) for the delivery of current and a series of anodes (15) facing the cathode cell bottom. The tops of the carbon blocks (10) forming the cathode cell bottom are shaped in such a way as to provide in the cell bottom a series of parallel channels (25) or grooves preferably coated with an aluminum-wettable refractory coating (35) covered in use by a pool (40) of molten aluminum or a layer of molten aluminum forming a drained surface. Movement of the aluminum pool (40) is decreased, cell operation improved and cell life extended.
    Type: Grant
    Filed: October 31, 1997
    Date of Patent: March 30, 1999
    Assignee: Moltech Invent S.A.
    Inventor: Vittorio de Nora
  • Patent number: 5876585
    Abstract: Roller clamps provide an economical and effective means to achieve steady and uniform current distribution through the anodes and cathode of an Hall-Heroult electrolytic cell during the pre-heat cycle. The roller clamps, which replace conventional bar clamps that are used in normal operation, have rollers adapted to bias anode support rods against electrical contacts on an anode bus bar with sufficient pressure to maintain desired electrical contact between the anode and contact; and to permit the anode supports to move to accommodate thermal expansion or deflections of cell components as the cell is heated.
    Type: Grant
    Filed: May 28, 1997
    Date of Patent: March 2, 1999
    Inventor: Rodney J. Schenk
  • 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: 5779875
    Abstract: The method includes the following step of forming at least one material input zone on the surface of an electrolyte, disposing a working tool in the input zone to push the material into the melt of the electrolyte, imparting mechanical oscillations and translatory motions to the working tool in the direction towards the electrolyte and back therefrom with the length of said motions being within the range of values from about 10.0 to about 120.0 sec. The method further includes transporting material into the input zone and forming some layer in the material input zone, and after accumulation of a sufficient amount of the material, the latter enters into contact with the working tool. The aforesaid steps increase the capacity of the material input zone and reduce power expenditures on the input of material into the electrolyte.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: July 14, 1998
    Assignee: Jury Alexeevich Budaev
    Inventors: Jury Alexeevich Budaev, Viktor Konstantinovich Kazantsev, Jury Petrovich Shelkovnikov, Igor Samsonovich Grinberg, Sergey Kokhanovsky, Vladimir Iliich Skornyakov, Petr Ivanovich Elagin, Leonid Viktorovich Ragozin
  • Patent number: 5759382
    Abstract: In an electrolysis cell wherein powdered material are added to a bath of molten electrolyte, the anode is provided with a duct through which the powdered material may be fed to the electrolyte. Simultaneously, a gas which is preferably inert, is also fed together with the powdered material through the duct, and both are injected beneath the surface of the electrolyte.
    Type: Grant
    Filed: September 20, 1996
    Date of Patent: June 2, 1998
    Assignee: Canadian Liquid Air Ltd/Air Liquide Canada LTEE
    Inventors: Torstein Utigard, Alejandro Bustos, Torbjorn Dahl
  • Patent number: 5730855
    Abstract: An anode positioning hoist supported on an overhead crane used in a smelting apparatus including a cathode with an upwardly facing surface and an anode with a downwardly facing surface. The anode positioning hoist includes a pair of channel members defining opposed vertical channels and a cylinder/piston assembly including a cylinder located between the channel members and a piston rod extending downwardly from the cylinder. A carrier is fixed to the piston rod for movement therewith and includes rollers guided in the channels. A connector assembly is mounted on the carrier to releasably secure the anode to the carrier. A control system including a counterbalance valve mounted on the cylinder and a pressure switch operates to cause extension of the piston rod until the downwardly facing surface of the anode engages the upwardly facing surface of the cathode. The control system thereafter causes retraction of the piston rod a predetermined distance to provide a desired anode-cathode gap.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: March 24, 1998
    Assignee: Harnischfeger Corporation
    Inventors: Roger D. Luebke, Randy H. Khoury
  • 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: 5667648
    Abstract: A closure is made of a flexible fabric material designed to withstand a temperature in the range of 1800.degree. F. as is present within a pot employed to conduct the Hall-Heroult process for deriving aluminum from alumina. The closure, in a preferred embodiment, includes an elongated hook allowing it to be hung over the opening of the pot and also includes a gripping handle allowing the closure to be manipulated. A peripheral bulbous seal enhances the sealing effect about the opening in the pot.
    Type: Grant
    Filed: March 18, 1996
    Date of Patent: September 16, 1997
    Assignees: Michael J. McDonald, Ben N. McDonald
    Inventor: James Barrett McDonald
  • Patent number: 5660710
    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 salt 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 31, 1996
    Date of Patent: August 26, 1997
    Inventor: Olivo Sivilotti
  • Patent number: 5618405
    Abstract: A method and apparatus for removing halides from high temperature gas mixtures (150.degree.-1000.degree. C.) using an electrochemical cell provided with inert electrodes and an electrolyte which will provide anions compatible with the halide anions formed at the anode. The electrolyte is elected to provide inert stable cations at the temperatures encountered. The gas mixture is passed by the cathode where the halides are converted to X.sup.-. The anions migrate to the anode where they are converted to a stable gaseous form at much greater concentration levels. Current flow may be effected by utilizing an external source of electrical energy or by passing a reducing gas such as hydrogen past the anode.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: April 8, 1997
    Assignee: Georgia Tech Research Corporation
    Inventor: Jack Winnick
  • Patent number: 5618403
    Abstract: A cell for the electrowinning of aluminium by the electrolysis of alumina dissolved in a molten fluoride-based electrolyte comprises a cathode composed of a carbon body having an aluminium resistant aluminium-wettable surface layer containing particulate titanium or other refractory hard metal boride and a bonding material providing a porous layer which contains cathodic molten aluminium. Molten cathodic aluminium external to the aluminium-resistant and aluminium-wettable surface contains refractory hard metal and boron in a total concentration sufficient or just below that sufficient to inhibit dissolution into the molten aluminium of the refractory hard metal boride. Alumina is fed to the cell whereby the required amount of titanium in the aluminium results from the alumina feed while, when boron is not present in a sufficient amount, boron is added to bring the total titanium and boron content to or just below the equilibrium solubility product.
    Type: Grant
    Filed: August 7, 1995
    Date of Patent: April 8, 1997
    Assignee: Moltech Invent S.A.
    Inventors: Vittorio de Nora, Jean-Jacques Duruz
  • Patent number: 5549799
    Abstract: An anode positioning hoist supported on an overhead crane used in a smelting apparatus including a cathode with an upwardly facing surface and an anode with a downwardly facing surface. The anode positioning hoist includes a pair of channel members defining opposed vertical channels and a cylinder/piston assembly including a cylinder located between the channel members and a piston rod extending downwardly from the cylinder. A carrier is fixed to the piston rod for movement therewith and includes rollers guided in the channels. A connector assembly is mounted on the carrier to releasably secure the anode to the carrier. A control system including a counterbalance valve mounted on the cylinder and a pressure switch operates to cause extension of the piston rod until the downwardly facing surface of the anode engages the upwardly facing surface of the cathode. The control system thereafter causes retraction of the piston rod a predetermined distance to provide a desired anode-cathode gap.
    Type: Grant
    Filed: December 31, 1992
    Date of Patent: August 27, 1996
    Assignee: Harnischfeger Corporation
    Inventors: Roger D. Luebke, Randy H. Khoury
  • Patent number: 5498320
    Abstract: In aluminum smelting by electrolysis, a double salt of KAlSO.sub.4, as a feedstock, is heated with a eutectic electrolyte, such as K.sub.2 SO.sub.4, at 800.degree. C. for twenty minutes to produce an out-gas of SO.sub.3 and a liquid electrolyte of K.sub.2 SO.sub.4 with fine-particles of Al.sub.2 O.sub.3 in suspension having a mean size of six to eight microns. This is pumped into a cell with an electrolyte comprised of K.sub.2 SO.sub.4 with fine-particles of Al.sub.2 O.sub.3 in suspension, an anode and a porous cathode of open-cell ceramic foam material. The cell is maintained at 750.degree. C. and four volts of electricity applied between the anode and the cathode causes oxygen to bubble at the anode and liquid aluminum to form in the porous cathode.
    Type: Grant
    Filed: December 15, 1994
    Date of Patent: March 12, 1996
    Assignee: Solv-Ex Corporation
    Inventor: John S. Rendall
  • Patent number: 5476574
    Abstract: A continuous feeder for feeding alumina to an aluminum reduction cell is positioned over a discharge outlet (114) of an alumina hopper. The feeder includes a flow control valve member (140) which is connected to a positioning means (132) by rod (142). The flow control valve member (140) includes a tapered section such that varying the vertical position of member (140) varies the clearance between the member (140) and an outlet orifice, which allows control over the flow rate of alumina from the hopper. The alumina flow control means is preferably mounted within an elongate tubular member (130), which is further mounted inside a housing (120). Housing (120) allows for removal of the flow control means for maintenance without having to first empty the hopper.
    Type: Grant
    Filed: September 29, 1994
    Date of Patent: December 19, 1995
    Assignee: Comalco Aluminium Limited
    Inventors: Barry J. Welch, David J. Stretch, Jennifer M. Purdie
  • Patent number: 5472578
    Abstract: A cell for the production of aluminium by the electrolysis of a molten electrolyte, in particular the electrolysis of alumina dissolved in a molten halide electrolyte such as cryolite, comprises anodes immersed in the molten electrolyte above a cell bottom whereon molten product aluminium is collected in a pool containing bodies of aluminium-resistant material. Under the anodes is at least one grid (10) of side-by-side upright or inclined walls (11,12) of aluminium-resistant material whose bottom ends stand on a ceramic-coated carbon cell bottom covered by the pool of molten aluminium. The bottom ends of the grid walls form a base which is large compared to the height of the walls, each grid (10) standing on the cell bottom and being removable from the cell. These grids reduce movements in the aluminium pool and their top parts may act as a drained cathode.
    Type: Grant
    Filed: September 16, 1994
    Date of Patent: December 5, 1995
    Assignee: Moltech Invent S.A.
    Inventor: Vittorio de Nora
  • Patent number: 5456808
    Abstract: A support structure for supporting continuous prebaked anodes in an aluminium smelting cell comprises a pair of side plates (3) and a pair of end plates (4) connected together to form an enclosed superstructure. The supporting structure includes at least one pair of spaced cross-plates (8, 9) that are configured to provide wedging surfaces which act to support an anode (14) therebetween. Electrical current is fed to the anodes via the cross-plates. Respective pairs of cross-plates supporting adjacent anodes may be spaced to define heat exchange passages which can be used to control the temperature of the support structure. A method for operating an aluminium smelting cell at variable amperage by positive and controlled extraction of heat from the cell is also described.
    Type: Grant
    Filed: April 22, 1994
    Date of Patent: October 10, 1995
    Assignee: Comalco Aluminium Limited
    Inventor: Drago D. Juric
  • Patent number: 5443707
    Abstract: An apparatus for electroplating a semiconductor substrate with a metallic film having a uniform thickness. Such a metallic film with a uniform thickness is formed by adjusting the arrangement of the anode so that the intensity distribution of the electric field generating on the main surface to be plated is made substantially uniform. The diameter of the anode is equal to or smaller than one-half that of the main surface of the semiconductor substrate so that the intensity distribution of the electric field on the main surface is substantially uniform. Further, the anode is formed into a mesh which amounts to an area factor equal to or smaller than 50%, which permits the fluctuation of the flux distribution of the plating solution to be neglected.
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: August 22, 1995
    Assignee: NEC Corporation
    Inventor: Hiroyuki Mori
  • Patent number: 5439563
    Abstract: A process for electrolytically producing magnesium metal from MgCl.sub.2 dissolved in an electrolyte, by conversion to the product metal and chlorine gas, wherein the MgCl.sub.2 content of the electrolyte is replenished by supplying thereto a feed having as components one or more magnesium chloride ammoniates for decomposition by the heat of the electrolyte into MgCl.sub.2 and ammonia gas. The feed, which may also include uncombined MgCl.sub.2, is delivered to the electrolyte at a location at which the generated ammonia does not come into reactive contact with the chlorine gas. The temperature of the electrolyte as well as its MgCl.sub.2 content can be controlled by selection of feed components, relative proportions, and rate of supply. The ammoniate content of the feed can be produced by reaction of ammonia with magnesium chloride hydrates, using the ammonia gas generated by the decomposition.
    Type: Grant
    Filed: August 25, 1993
    Date of Patent: August 8, 1995
    Assignee: Alcan International Limited
    Inventor: Olivo G. Sivilotti
  • Patent number: 5435897
    Abstract: Automatized equipment for the replacement of the anodes in the cells for aluminum production, comprising two modular structures suspended from saddles sliding on a bridge crane provided in the cell room, the first structure being provided with devices for crust breaking, the removal and laying of worn anodes on a platform translable on a special vehicle placed on a side of the cells, and then for hooking new anodes placed on the same platform and positioning them into the hollow space of the removed worn anodes and the second structure being provided with a device for cleaning the hollow space, and for collecting and transferring slags into a special container placed at the opposite side of the cells on a special vehicle, as well as of means for covering with alumina and/or other powdery materials the new repositioned anodes.
    Type: Grant
    Filed: February 1, 1994
    Date of Patent: July 25, 1995
    Assignee: Techmo Car S.p.A.
    Inventor: Gianfranco Zannini