Treating Slag Or Dross Patents (Class 75/672)
  • Patent number: 11859906
    Abstract: A compressing element, devices for using such a compressing element and methods of use are provided, in which the compressing element has: a upper surface provided with an inlet and an outlet; a lower surface; an at least partially hollow interior provided between the upper surface and the lower surface, the hollow interior being connected to the inlet and the outlet; the hollow interior being provided with: one or more fluid flow constraining surfaces provided by one or more walls of the follow interior; and one or more fluid flow control elements provided in the hollow interior, the one or more fluid flow control elements being additional to the one or more fluid flow constraining surfaces provided by the one or more walls of the hollow interior. The arrangement of inlet, outlet, fluid flow constraining surfaces and fluid control elements provides for improved cooling of the compressing element, for instance when used to press molten metal processing by-products to extract molten metal.
    Type: Grant
    Filed: August 10, 2020
    Date of Patent: January 2, 2024
    Assignee: ALTEK EUROPE LIMITED
    Inventors: Alan Peel, Andrew Gibbs
  • Patent number: 9993796
    Abstract: Disclosed are a reactor and agitator useful in a high pressure process for making 1-chloro-3,3,3-trifluoropropene (1233zd) from the reaction of 1,1,1,3,3-pentachloropropane (240fa) and HF, wherein the agitator includes one or more of the following design improvements: (a) double mechanical seals with an inert barrier fluid or a single seal; (b) ceramics on the rotating faces of the seal; (c) ceramics on the static faces of seal; (d) wetted o-rings constructed of spring-energized Teflon and PTFE wedge or dynamic o-ring designs; and (e) wetted metal surfaces of the agitator constructed of a corrosion resistant alloy.
    Type: Grant
    Filed: March 26, 2015
    Date of Patent: June 12, 2018
    Assignee: Honeywell International Inc.
    Inventor: Stephen A. Cottrell
  • Patent number: 9260766
    Abstract: Embodiments of an aluminum dross cooling head are disclosed. The cooling cooperates with a material container encapsulate dross and reduce thermiting of the dross. In one embodiment, the cooling head also serves as a compression head when forced into the dross by a cooperating dross press assembly.
    Type: Grant
    Filed: October 4, 2013
    Date of Patent: February 16, 2016
    Assignee: ALTEK, L.L.C.
    Inventors: James Herbert, Jorge Fernandez, Andy Gibbs
  • Patent number: 8685138
    Abstract: A tilting rotary furnace with a door assembly that seals against a furnace vessel. The seal between the door and the furnace vessel allows for regulation of the internal environment of the furnace and control over thermitting of the aluminum. As a result, aluminum recovery may be carried out without the use of salt. A portion of the door may rotate with the furnace vessel and a portion of the door may remain rotationally stationary with respect to the furnace vessel and the rotating portion of the door.
    Type: Grant
    Filed: September 11, 2012
    Date of Patent: April 1, 2014
    Assignee: Altek L.L.C.
    Inventor: Erik D. Grimm
  • Patent number: 8641801
    Abstract: An aluminum dross cooling head cooperates with a material container to encapsulate dross and reduce thermiting of the dross. In one embodiment, the cooling head also serves as a compression head when forced into the dross by a cooperating dross press assembly.
    Type: Grant
    Filed: May 8, 2012
    Date of Patent: February 4, 2014
    Assignee: Altek, L.L.C.
    Inventors: James Herbert, Jorge Fernandez, Andy Gibbs
  • Publication number: 20130186236
    Abstract: A process and an apparatus are disclosed for improved recovery of metal from hot and cold dross, wherein a dross-treating furnace is provided with a filling material with capacity to store heat. This filling material is preheated to a desired temperature by injection of an oxidizing gas to burn non-recoverable metal remaining in the filling material after tapping of the recoverable metal contained in the dross and discharging of the treatment residue. When dross is treated in such furnace, the heat emanating by conduction from the filling material is sufficient to melt and separate the recoverable metal contained in the dross, without addition of an external heat source, such as fuel or gas burners, plasma torches or electric arcs and without use of any salt fluxes. Furthermore, the recovered metal being in the molten state can be fed to the molten metal holding furnace without cooling the melt.
    Type: Application
    Filed: October 18, 2012
    Publication date: July 25, 2013
    Applicant: PYROGENESIS CANADA INC.
    Inventor: Pyrogenesis Canada Inc.
  • Patent number: 8206486
    Abstract: Embodiments of an aluminum dross cooling head are disclosed. The cooling cooperates with a material container encapsulate dross and reduce thermiting of the dross. In one embodiment, the cooling head also serves as a compression head when forced into the dross by a cooperating dross press assembly.
    Type: Grant
    Filed: May 21, 2010
    Date of Patent: June 26, 2012
    Assignee: Altek, L.L.C
    Inventors: James Herbert, Jorge Fernandez, Andy Gibbs
  • Patent number: 8119060
    Abstract: A solder recovery device includes a melter which melts solder dross stored in a melting crucible, an agitation unit which agitates the melted solder dross, so as to separate the melted solder dross up and down into an oxidized residue and a recycled solder in the melting crucible, and a suction unit which sucks the oxidized residue generated by the agitation, the suction unit sucking the oxidized residue in an upper portion of the melting crucible to be removed.
    Type: Grant
    Filed: January 21, 2010
    Date of Patent: February 21, 2012
    Assignee: Ricoh Company, Ltd.
    Inventor: Takehiro Inuma
  • Patent number: 7829460
    Abstract: By forming an aluminum nitride layer by a self-limiting process sequence, the interface characteristics of a copper-based metallization layer may be significantly enhanced while nevertheless maintaining the overall permittivity of the layer stack at a lower level.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: November 9, 2010
    Assignee: GLOBALFOUNDRIES, Inc.
    Inventors: Christof Streck, Volker Kahlert
  • Patent number: 7655067
    Abstract: The invention relates to a method for processing aluminum in a furnace consisting in introducing an aluminum-containing material and possibly one or several types of salt into the furnace, melting said material by heating with the aid of at least one burner supplied with a combustive material and fuel in such a way that a molten aluminum possibly covered with a slag containing, in particular alumina and at least one salt is produced and in measuring a carbon monoxide and/or hydrogen concentration in the furnace atmosphere or in a smoke at the exit of the furnace. Oxygen content in the combustive material supplying at least one burner is greater than 10% by volume, preferably greater than 21% by volume.
    Type: Grant
    Filed: February 7, 2005
    Date of Patent: February 2, 2010
    Assignee: L'Air Liquide-Societe Anonyme a Directoire et Conseil de Surveillande pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Nicolas Lucas, Bernard Zamuner
  • Patent number: 6767382
    Abstract: An apparatus for separating molten aluminium from a mixture of molten aluminium and aluminium dross includes a table for supporting an insulated crucible containing the mixture of molten aluminium and aluminium dross. A rotatable frame supports a plurality of tines which can be lowered into the mixture in the crucible for stirring the mixture. Vibration means are provided enabling simultaneous vibration of the crucible and stirring of the mixture. The tines cuts through the dross in a shearing action gently rolling the dross, mixing and tumbling it and causing the droplets of aluminium to coalesce. The aluminium droplets and particles in the dross coalesce to form larger droplets and gradually sink to the base of the crucible. A screening means is disposed to substantially surround the crucible when it is supported by the table, which includes a door to both allow and prevent access to the crucible.
    Type: Grant
    Filed: July 2, 2003
    Date of Patent: July 27, 2004
    Assignee: Mawar Malaysian Limited
    Inventors: Andreas Stratigos, Brendan O'Neill
  • Patent number: 6572675
    Abstract: A furnace system for recovering a non-ferrous metal from a charge of material containing the metal. The furnace system having a furnace chamber having walls defining a refractory chamber, the refractory chamber receiving the charge of material and the metal contained in the charge of material being heated into a flowable mode in the refractory chamber. The furnace system having at least one paddle radially projecting from an interior surface of the furnace chamber toward a longitudinal axis of the furnace chamber. Other features of the invention include a door having a closed position adjacent an inlet passage to the furnace chamber, the door having rollers and a suspension. Other features of the invention include a motor and a control unit which monitors torque to rotate the furnace chamber as an indication of viscosity of the charge of material. Methods of operating a furnace system for recovering non-ferrous metal from a charge of material containing the metal are also discussed.
    Type: Grant
    Filed: August 6, 2001
    Date of Patent: June 3, 2003
    Assignee: MDY L.L.C.
    Inventor: Moshe Yerushalmi
  • Patent number: 6454832
    Abstract: A manufacturing process for an intermediate product made of a predetermined 7000 series alloy having a target content of at least one first anti-recrystallizing element Z1 selected from the group consisting of Zr and Cr. This process enables effective recycling of scrap, particularly machining scrap made of 7000 series alloys, in the manufacture of intermediated products with high added value.
    Type: Grant
    Filed: November 13, 2000
    Date of Patent: September 24, 2002
    Assignee: Pechiney Rhenalu
    Inventors: Jean-Francois Verdier, Michel Leroy, Laurent Calaque
  • Patent number: 6296817
    Abstract: Disclosed is the recycling of aluminum dross. Aluminum dross is crushed into particles which are size-classified on the basis of 1 mm. The aluminum dross particles equal to or smaller than 1 mm in size are leached with an aqueous sodium hydroxide solution to give a leachate which contains sodium aluminate as a result of the reaction the aluminum metal of the aluminum dross particles with sodium hydroxide. The aluminum dross particles greater than 1 mm in size are remelted to recover aluminum metal. In the leachate, a small quantity of aluminum hydroxide is seeded, followed by hydrolyzing the sodium aluminate to obtain aluminum hydroxide. Meanwhile, the leachate is filtered to obtain a residue. This residue is subjected to washing, drying and roasting. The mixing of the roasted residue with aggregate and alumina cement gives alumina castable refractories.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: October 2, 2001
    Inventors: Hyung-Kyu Park, Hoo-In Lee, Eui-Pak Yoon
  • Patent number: 6293990
    Abstract: A manufacturing process for an intermediate product made of a predetermined 7000 series alloy having a target content of at least one first anti-recrystallizing element Z1 selected from the group consisting of Zr and Cr. The product is produced by the steps of: a) supplying machining scrap including at least one second 7000 series alloy having a target content of at least one second anti-recrystallizing element Z2 selected from the group consisting of Zr and Cr, in an amount greater than a maximum accepted content of Z2 in the predetermined alloy; b) conducting at least one refining step of said scrap to reduce the amount of Z2 to a value below the maximum accepted content of Z2 in the predetermined alloy; c) producing a batch of liquid metal having nominal composition, in part or in whole, from the refined scrap; and d) forming the product by casting the liquid metal.
    Type: Grant
    Filed: January 10, 2000
    Date of Patent: September 25, 2001
    Assignee: Pechiney Rhenalu
    Inventors: Jean-Francois Verdier, Michel Leroy, Laurent Calaque
  • Patent number: 6217631
    Abstract: A method of heating a body of molten metal passing through a treatment bay. The method comprises providing a body of molten metal in a treatment bay and providing a baffle heater in the treatment bay to contact the molten metal. The baffle heater is comprised of a member fabricated from a material substantially inert to the molten metal, the member containing at least one heating element receptacle. An electric heating element is positioned in the receptacle for heating the member, the element protected from the molten metal by the material constituting the member.
    Type: Grant
    Filed: March 27, 1999
    Date of Patent: April 17, 2001
    Inventor: C. Edward Eckert
  • Patent number: 6159269
    Abstract: A process and an apparatus are disclosed for improved recovery of metal from dross, wherein a dross treating furnace is provided with a refractory wall or lining with good capacity to store and conduct heat. This furnace is preheated to a desired temperature by injection of oxygen to burn non-recoverable metal remaining in the residue after tapping of the recoverable metal contained in the dross. When dross is treated in such preheated furnace, the heat emanating by conduction from the furnace wall is sufficient to melt and separate the recoverable metal contained in the dross, without addition of an external heat source, such as fuel or gas burners, plasma torches or electric arcs.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: December 12, 2000
    Assignee: Pyrogenesis Inc.
    Inventors: Michel G. Drouet, Peter G. Tsantrizos
  • Patent number: 5900039
    Abstract: Process for obtaining a metallic phase from a dispersed mixture composed of one of (a) at least one metal selected from the group consisting of a light metal or an alloy of the at least one metal, and mixtures thereof, and (b) at least one non-metallic phase composed of at least one member selected from the group consisting of at least one oxide, an oxide compound, and other compounds of the at least one metal at higher temperatures. The process includes introducing the dispersed mixture into a metallurgical vessel; at least one of heating and adjusting a temperature of the dispersed mixture to between 20 and 250.degree. C. above the liquidus temperature of the metallic phase; rotating the metallurgical vessel to homogenize the dispersed mixture and to produce a pourable dispersed mixture; uniformly distributing the pourable dispersed mixture around a rotational axis of the metallurgical vessel; and increasing a radial acceleration of the pourable dispersed mixture of at least 1 g.
    Type: Grant
    Filed: January 27, 1997
    Date of Patent: May 4, 1999
    Inventor: Bernd Kos
  • Patent number: 5788918
    Abstract: A dross press is enclosed within a cabinet which is normally maintained at a negative pressure relative to ambient air pressure. The cabinet is provided with locked doors to prevent egress of explosive gases or pieces of metal. The cabinet is also equipped with safety vents at a high level to prevent destruction of the cabinet by internal explosions. The cabinet also is provided with a fan for extracting fumes therefrom. The fan is connected to a purifier to treat the extracted fumes and air inlet holes in the press head so that the fan may draw air through the head for cooling.
    Type: Grant
    Filed: June 27, 1997
    Date of Patent: August 4, 1998
    Inventor: Alan Bramley
  • Patent number: 5716426
    Abstract: The processing of aluminium dross containing Al and Al.sub.2 O.sub.3 originating from aluminium production, comprises the steps of separating aluminium from the dross to produce a dross residue and reacting the dross residue at a temperature above 1360.degree. C. with a calcium-oxygen compound to form calcium aluminate as an at least partially melted material. To obtain a product specially suitable for use in steel-making, the calcium aluminate is rapidly cooled to form a glassy solid product. The two steps may be performed in the same vessel, which has a suitable refractory lining.
    Type: Grant
    Filed: March 22, 1996
    Date of Patent: February 10, 1998
    Assignee: Hoogovens Staal B. V.
    Inventors: Christiaan M. J. M. Beelen, Willem Van Der Knoop
  • Patent number: 5669957
    Abstract: A dross compression apparatus and method utilizes a dross compression head and a skim box or collector having mating ribs. The ribs may be any type of projection or shape of the head and skim box sufficient to form grooves in both sides of the dross which divide or substantially divide the dross. Improved plating of the aluminum metal and separation of the aluminum layers from the aluminum oxide are achieved by using pressures in the range of 50 to 70 pounds per square inch. The ribs by their cutting action through the dross enable the achieving of these pressures with lower rated hydraulic presses. Two specific embodiments are disclosed, one utilizing an elongated substantially hemispheric shaped head and the other utilizing a substantially hemispheric shaped head. In both embodiments, the head and receptacle or skim box are of substantially conforming shapes.
    Type: Grant
    Filed: June 12, 1996
    Date of Patent: September 23, 1997
    Assignee: Altek International, Inc.
    Inventor: David J. Roth
  • Patent number: 5613996
    Abstract: A process for treatment of aluminum dross residue (NMP) having available aluminum nitride (AlN) and/or free aluminum (Al) and/or aluminum chlorides (AlCl.sub.3) having a particle size within the range of 0.3 to 300 microns, i.e., "fines" to produce a high alumina lightweight aggregate is described. The process is characterized in that the NMP is fed into a rotating sealed kiln and heated to a temperature in the range of 2000.degree. to 4000.degree. F. while feeding oxygen or a mixture of oxygen and water into the kiln with less than about 20% of the total heat energy input for heating the NMP to a temperature between 2000.degree. and 4000.degree. F. being supplied from an external source. The process does not require prior agglomerization of the fines.
    Type: Grant
    Filed: May 8, 1995
    Date of Patent: March 25, 1997
    Assignee: Plasma Processing Corporation
    Inventor: Richard D. Lindsay
  • Patent number: 5599379
    Abstract: Method and apparatus for recovering free aluminum from a metal bearing dross containing free aluminum metal and oxides of the metal. Hot dross is collected from a hot dross source into a vessel, and the vessel is placed into a sealable storage container. The storage container is insulated to maintain heat generated by the hot dross within the interior of the storage container to maintain the dross at or near its temperature when first placed in the storage container. An inert gas is then introduced into the container to purge the container of all gasses other than the inert gas. The inert gas reduces thermiting of the hot dross and limits the cooling of the hot dross in order to maintain the hot dross at an elevated temperature while the hot dross remains in the storage container. The dross is then removed from the vessel and introduced dross into a dross processing device such as a furnace.
    Type: Grant
    Filed: March 29, 1995
    Date of Patent: February 4, 1997
    Inventors: Han Spoel, William A. Zebedee
  • Patent number: 5563903
    Abstract: An aluminum melting method wherein an atmosphere above the aluminum charge is comprised of two strata, a lower strata covering the aluminum charge comprised of a non-oxidizing gas and an upper strata comprised of combustion gases from one or more burners. Heat from the burner or burners radiatively heats and melts the aluminum while the lower strata protects the aluminum from oxidative effects which would result if the aluminum surface were contacted with the combustion gases, thus serving to reduce dross formation.
    Type: Grant
    Filed: June 13, 1995
    Date of Patent: October 8, 1996
    Assignee: Praxair Technology, Inc.
    Inventors: Fatemeh F. Jebrail, Arthur W. Francis, Jr., Hisashi Kobayashi
  • Patent number: 5540752
    Abstract: A process and apparatus are disclosed for recovering a non-ferrous metal, preferably aluminum and aluminum alloys, in molten coherent form from a charge of material to be processed containing the metal. The charge is introduced into a sealable furnace which is then sealed. The charge is agitated. A control parameter indicative of conditions inside said furnace is monitored and compared to a pre-determined first condition for the parameter. A heat source is operated to heat the charge until the control parameter reaches the first condition. The operation of the heat source is then stopped. A controlled amount of oxidizing agent and an inert carrier is then introduced into the furnace. The control parameter is monitored and compared to a predetermined second condition for the parameter. The flow of the oxidizing agent and the carrier is controlled to maintain the control parameter at about the second condition. The molten metal is subsequently removed from the furnace.
    Type: Grant
    Filed: February 24, 1994
    Date of Patent: July 30, 1996
    Inventor: Han Spoel
  • Patent number: 5527380
    Abstract: A method for recovering non-ferrous metal from a dross that includes the non-ferrous metal includes introducing the dross into a rotary furnace or rotatable converter. The furnace or converter has a refractory lining. Oxygen and a fossil fuel are supplied to an oxy-fuel burner. The oxygen is supplied as a combustion gas including at least eighty percent oxygen. The oxygen and fossil fuel are combusted to generate an initial combustion energy. The dross is heated to a temperature above a melting point of the non-ferrous metal by supplying the initial combustion energy to the furnace or converter. The heating takes place in the absence of a protective salt layer. The non-ferrous metal and a non-metallic residue are recovered from the furnace or converter.
    Type: Grant
    Filed: October 19, 1994
    Date of Patent: June 18, 1996
    Assignees: AGA Aktiebolag, Hoogovens Aluminium Huttenwerk GmbH
    Inventors: Henrik Gripenberg, Hans-Walter Grab, Michael Mullerthann
  • Patent number: 5525141
    Abstract: Process and apparatus for the treatment of light metals. The present invention pertains to a process for the treatment of mixtures of at least one light metal and at least one nonmetallic phase, formed of at least one oxide of a light metal, particularly of slag and waste metals for a subsequent process for the separation of the metallic phase as well as an apparatus for carrying out the process or the preparation of the mixture for disintegration, wherein the mixture, slag or waste metals and, if necessary, additions for the formation of a charge, are loaded into a treatment container or receptacle, overheated a maximum of 380.degree. C. and the phases, via motion, are dispersed and/or held in dispersement, whereafter the homogenized charge, set up with the parameters for the subsequent process, is removed and subjected to separation.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: June 11, 1996
    Inventors: Bernd Kos, Harald Marhold
  • Patent number: 5500033
    Abstract: A method of heating a melt containing an oxidizable substance in which a fuel is burned with an oxidant by projecting fuel oxidant jets over the melt. The fuel and the oxidant jets have a fuel jet momentum and an oxidant jet momentum, respectively. The oxidant jet produces a top oxidation layer on the top surface of the melt and such top oxidation layer has a thickness. The oxidant jet momentum is adjusted to be below a threshold momentum at which the top oxidation layer is forces aside by the oxidant jet to expose fresh melt that potentially can be oxidized and can increase the thickness of the top oxidation layer. The fuel-jet momentum is adjusted so that it is greater than the oxidant jet momentum to draw the oxidant jet towards the fuel jet and thereby forms a desired combustible mixture in a mixing layer.
    Type: Grant
    Filed: February 27, 1995
    Date of Patent: March 19, 1996
    Assignee: The BOC Group, Inc.
    Inventor: Loo T. Yap
  • Patent number: 5470376
    Abstract: A process of recovering a non-ferrous metal from a dross containing the same. The process involves introducing into a rotary furnace the dross and a fluoride compound which becomes substantially molten above the melting point of the metal, heating the dross and fluoride compound to a maximum temperature above the melting point of the metal, using a heating device which substantially maintains a non-oxiding atmosphere in the furnace, rotating the furnace until the dross reaches the maximum temperature, removing the molten metal thereby separated from a solid dross residue and removing the solid dross residue from the furnace. The fluoride compound, which may be, for example, cryolite, recovered cryolite, AlF.sub.3 or NaF, or a mixture thereof, is such that it remains in the dross during the process and does not make the dross become sticky.
    Type: Grant
    Filed: July 15, 1994
    Date of Patent: November 28, 1995
    Assignee: Alcan International Limited
    Inventors: Ghyslain Dube, Marko Litalien, Roger Pelletier, Zhou Wang
  • Patent number: 5447548
    Abstract: A process for recovering free aluminum and aluminum compounds such as aluminum oxide from aluminum dross and aluminum scrap in a furnace heated with a plasma arc torch followed by oxygen injection after significant aluminum separation has occurred is described. The injected oxygen reacts with aluminum nitrides and unrecoverable aluminum in the dross to provide processing energy. High aluminum recovery is obtained with greatly reduced cycle times at lower overall operating costs.
    Type: Grant
    Filed: May 2, 1994
    Date of Patent: September 5, 1995
    Assignee: Plasma Processing Corporation
    Inventor: Richard D. Lindsay
  • Patent number: 5439501
    Abstract: A method of processing hot dross resulting from an aluminum smelting process is carried out as follows. First, the hot dross is filled in a hollow container which has a porous bottom plate closing a bottom opening of the container. A solid plate is placed on the filled hot dross. Then, an impact load is applied successively on the hot dross via the solid plate by an appropriate hammer mechanism. By the application of successive impact load, the air and aluminum content in a molten state are expelled from the dross and discharged through the porous bottom plate. The resultant solidified dross contains metal aluminum content without oxidized or nitrided, and therefore is suitable for use as a deoxidant utilized in deoxidizing process of oxidation smelting of steel.
    Type: Grant
    Filed: November 12, 1993
    Date of Patent: August 8, 1995
    Assignees: Yamaichi Metal Co., Ltd., Yamaichi System Produce Co. Ltd.
    Inventors: Katsuzo Watanabe, Yoshihito Taki
  • Patent number: 5421856
    Abstract: Dross formation in the aluminum melting and/or refining is avoided partially or totally by the method of this invention. The method is useful in unmodified open top furnaces. The elimination or reduction of dross formation is carried out throughout the body of molten aluminum by the installation of gas injection devices to extend through the refractory lining in the bottom of the furnace. For longer life without clogging metal cased refractories of the directional porosity type are used for gas injection. Mixtures of inert and hydrocarbon gases are used with respective proportions chosen to match the design parameters of different types of furnaces. In operation the dross is eliminated by reactions of the injected gases with the impurities of the molten aluminum batch at its hottest temperatures in the body of the aluminum mass to thereby reduce dross generally caused by oxidation of the molten aluminum within the molten mass.
    Type: Grant
    Filed: March 28, 1994
    Date of Patent: June 6, 1995
    Inventor: Arturo Lazcano-Navarro
  • Patent number: 5421850
    Abstract: A method and apparatus for treating non-ferrous metal drosses in order to recover the free metal contained therein. The dross is heated by a plasma torch in a rotary furnace, preferably to a temperature above 800.degree. C. The plasma heating and rotary motion make it possible to recover metal from the dross without employing the conventional salt bath. This means that the gases exiting the furnace can be treated more easily to remove pollutants and the solid residues can be discarded without risk of causing environmental pollution. By controlling the speed of rotation of the furnace, large dross lumps can be accommodated and so the conventional grinding and screening procedure of the dross can advantageously be eliminated.
    Type: Grant
    Filed: April 28, 1993
    Date of Patent: June 6, 1995
    Assignee: Alcan International Limited
    Inventors: Ghyslain Dube, Jean-Paul Huni, Serge Lavoie, Wesley D. Stevens
  • Patent number: 5407459
    Abstract: The present invention is concerned with a process for the preparation of sintered calcium aluminates that can generally be used as a protective cover for liquid metals, and particularly steel, and the process comprising the steps of mixing calcium oxide, or its precursor, particles and aluminum dross residue, such as NOVAL.TM.; calcining the resulting mixture; maintaining a calcining temperature of 1200.degree. C. or higher for approximately 5 minutes or more which is sufficient to form a friable sintered product rich in calcium aluminates; and recovering the sintered product after cooling. Optionally, calcium fluoride, or other fluoride can be added to the starting mixture, if it is not already contained in the dross residue.
    Type: Grant
    Filed: September 23, 1993
    Date of Patent: April 18, 1995
    Assignees: Alcan International Limited, Les Sables Olimag Inc.
    Inventors: Raymond Breault, Sylvain P. Tremblay, Yvan Huard, Gilles Mathieu
  • Patent number: 5405427
    Abstract: Disclosed is an improved flux comprising 32 to 61 wt. % sodium chloride, 2 to 15 wt. % magnesium chloride, 2 to 12 wt. % carbon, the remainder potassium chloride.
    Type: Grant
    Filed: May 18, 1994
    Date of Patent: April 11, 1995
    Inventor: C. Edward Eckert
  • Patent number: 5401294
    Abstract: The invention concerns a process for de-metallization of metal-containing residues, dross, slags and the like that accumulate during thermal processes in metallurgical and scrap metal reclamation processes which consists of that the metal/non-metal phase mixture is fed into a centrifuge mold at a temperature within the mentioned temperature range or after having been fed into it is brought to the temperature mentioned, there in a first process phase, while maintaining the temperature within the mentioned range, it is subjected to radial acceleration for a specified time until a required degree of de-metallization is achieved and that in a second phase of the process by maintaining the radial acceleration by means of rotation at least the metallic phase, separated and removed from the phase mixture and arranged on the outside periphery is brought to solidification or setting by lowering its temperature, after which the metal phase when reaching the handling temperature is removed as at least one body whose out
    Type: Grant
    Filed: April 29, 1993
    Date of Patent: March 28, 1995
    Inventors: Bernd Kos, Harald Marhold
  • Patent number: 5397104
    Abstract: A dross compression apparatus utilizes a substantially hemispheric shaped receptacle in a dross collector and a complementing compression head which is provided with ribs to form grooves in the material formed between the head and the receptacle. The material formed between the head and the receptacle is substantially a shell comprised of an inner layer of aluminum oxide and outer layers of aluminum. The grooves in the shell enable the material to be more easily processed as the shell is readily broken for crushing. The compression head may be applied more than once to the aluminum dross and may be rotated between applications causing multiple grooves and increased decanting of aluminum. The compression head is provided with a water cooling system which more rapidly cools the aluminum dross and reduces the thermite reaction. The cast steel compression head reduces the air flow to the cooling dross thereby reducing the amount of oxygen available, oxidation and the thermite reaction.
    Type: Grant
    Filed: November 22, 1993
    Date of Patent: March 14, 1995
    Assignee: Altek International
    Inventor: David Roth
  • Patent number: 5330618
    Abstract: A process and system for treating aluminum salt cake containing water soluble halide salts by contacting the salt cake with water to dissolve water soluble halide salts forming a saturated brine solution. Transporting a portion of about 25% of the saturated brine solution to a reactor and introducing into the saturated brine solution at least an equal volume of a water-miscible low-boiling organic material such as acetone to precipitate a portion of the dissolved halide salts forming a three-phase mixture of an aqueous-organic-salt solution phase and a precipitated salt phase and an organic rich phase. The precipitated salt phase is separated from the other phases and the organic rich phase is recycled to the reactor. The remainder of the saturated brine solution is sent to a multiple effect evaporator having a plurality of stages with the last stage thereof producing low grade steam which is used to boil off the organic portion of the solution which is recycled.
    Type: Grant
    Filed: December 10, 1992
    Date of Patent: July 19, 1994
    Assignee: University of Chicago
    Inventors: Edward J. Daniels, Bassam J. Jody, Patrick V. Bonsignore
  • Patent number: 5308375
    Abstract: A process for recovering free aluminum and aluminum compounds such as aluminum oxide from aluminum dross and aluminum scrap in a furnace heated with a plasma arc torch followed by oxygen injection after significant aluminum separation has occurred is described. The injected oxygen reacts with aluminum nitrides and unrecoverable aluminum in the dross to provide processing energy. High aluminum recovery is obtained with greatly reduced cycle times at lower overall operating costs.
    Type: Grant
    Filed: June 22, 1992
    Date of Patent: May 3, 1994
    Assignee: Plasma Processing Corporation
    Inventor: Richard D. Lindsay
  • Patent number: 5290535
    Abstract: Saltcake generated by the aluminum industry is completely recycled through a process that simultaneously liberates the contained aluminum metal and dissolves the soluble salt fluxes to recover aluminum metal, aluminum oxide and salt fluxes by temperature controlled wet milling, rapid solids-brine separation and solar pond evaporation of the resulting clear brine. The temperature of the feedwater is 70.degree. F. or less to retard the exothermic reaction of aluminum metal with water, thereby minimizing the loss of metal to oxidation and the evolution of undesirable gases. Low temperature is maintained by using process water at or below the desired temperature, by forcibly cooling the mill with ambient air, and by controlling transit time through the mill to avoid excessive grinding of the aluminum metal. Minimizing the production of fine aluminum particles reduces the total surface area of aluminum metal available for exothermic reacton with the water.
    Type: Grant
    Filed: April 9, 1993
    Date of Patent: March 1, 1994
    Assignee: IMSALCO
    Inventors: Dale A. Zuck, Gene J. Kulik, Henry C. Johns
  • Patent number: 5286274
    Abstract: This is a method for treatment of spent potlining from aluminium reduction cells including the refractory material in order to transfer the spent potlining to a form in which it can be used as a filler or as a raw material. The spent potlining is crushed and supplied to a closed electrothermic smelting furnace optionally together with a SiO.sub.2 source, wherein the spent potlining is melted at a temperature between 1300.degree. and 1750.degree. C. An oxidation agent is supplied to the furnace in order to oxidize carbon and other oxidizable components contained in the spent potlining such as metals, carbides and nitrides. Further, a source of calcium oxide is supplied to the smelting furnace in an amount necessary to react with all fluoride present to form CaF.sub.2 and to form a calcium aluminate or calcium aluminate silicate slag containing CaF.sub.
    Type: Grant
    Filed: November 3, 1992
    Date of Patent: February 15, 1994
    Assignee: Elkem Technology a/s
    Inventors: Jon G. Lindkvist, Terje Johnsen
  • Patent number: 5259867
    Abstract: In a metallurgical process, a unique materials conservation and environmental process for treating cross materials at the site of a melting chamber by applying a preselected fines suppressing agent to stages of the dross materials promptly after removal from the melting chamber.
    Type: Grant
    Filed: June 1, 1992
    Date of Patent: November 9, 1993
    Inventor: Willem J. Hagendoorn
  • Patent number: 5242486
    Abstract: The invention relates to a coolant of aluminium dross, which used in separating and recovering metallic aluminium involved in the dross which is formed when aluminium and aluminium alloys are molten. The coolant consists of 4-60% by weight of a crabonaceous material wherein the particles whose size is 2-7 mm in diameter are not less than 50% by weight, and 4-60% by weight of at least one of obsidian, perlite, vermiculite and natural pumice whose particle size is 2-7 mm in diameter. Alternately, the coolant consists of 20-50% by weight of the carbonaceous material wherein the particles whose size 2-7 mm in diameter are not less than 50% by weight, 20-50% by weight of at least of obsidian, perlite, vermiculite and natural pumice whose particle size is 2-7 mm in diameter, and not more than 30% by weight of at least one of SiC or metal oxides such as of Al, Si Zr, Cr and Zn. Preferably, said carbonaceous material is at least one of coke and charcoal.
    Type: Grant
    Filed: April 1, 1992
    Date of Patent: September 7, 1993
    Assignee: Epoleon Corporation
    Inventors: Shinobu Fukushige, Masayoshi Sakashita, Tadashi Mantani
  • Patent number: 5135565
    Abstract: A process and apparatus for recovering aluminum from a solid dross containing the same comprising: (a) continuously introducing the dross and lime flux into an inert gas DC transferred arc plasma torch furnace, (b) heating the mixture to above the slag melting point to form two immiscible layers, and (c) periodically removing the upper aluminum layer and the lower residual slag layer.
    Type: Grant
    Filed: April 16, 1991
    Date of Patent: August 4, 1992
    Assignee: The BOC Group, Inc.
    Inventor: Theodore Gens
  • Patent number: 5032177
    Abstract: By means of an electromagnetic stirrer there is produced in the melt within the melt chamber of the melting furnace a turbulent flow or pair of turbulent flows working in opposite directions and each having a substantially vertical turbulent flow axis. By means of this turbulent flow the upwardly floating slag is forced towards the outermost turbulent flow lines or regions and into an auxiliary chamber formed between a slag barricade and the furnace door. The melt can flow back from the auxiliary chamber into the melt chamber. The slag collected in the auxiliary chamber can be removed in predeterminate time intervals from the auxiliary chamber by means of a slag removal sliding or pusher element and disposed in an environmentally protective fashion in a slag container moved into position at the opened furnace door.
    Type: Grant
    Filed: July 19, 1990
    Date of Patent: July 16, 1991
    Assignee: Gautschi Electro-Fours SA
    Inventors: Hans-Otto Jochem, Franz Engelberg
  • Patent number: 5013356
    Abstract: The present invention relates to a process and a plant for the processing of saline slag from the melting of aluminium scrap and waste with a saline flux in which the salts constituting the flux are recovered and other components of the slag are separated. The harmful or toxic gases developed during this processing are subjected to combustion to produce flue gases dispersible in the atmosphere with recovery of combustion heat, preferably used over in processing the slag.
    Type: Grant
    Filed: January 16, 1990
    Date of Patent: May 7, 1991
    Assignee: Engitec Impianti S.p.A.
    Inventors: Marco Olper, Tullio Corsini, Pierluigi Fracchia
  • Patent number: 4983216
    Abstract: Disclosed is a method of melting aluminum scrap and removing skim therefrom having reduced amounts of aluminum contained therein. Melted scrap and salt is added to a body of molten aluminum in a skim removal bay and a layer containing salt and skim is collected on the surface of the body, the layer containing high levels of molten aluminum in lower regions of said layer. The layer is treated so that upper regions thereof contain reduced amounts of aluminum, the treating aiding molten aluminum in the layer to return to the body. A portion of the treated layer is removed from upper regions thereof, the portion comprised of salt, skim and aluminum.
    Type: Grant
    Filed: February 12, 1990
    Date of Patent: January 8, 1991
    Assignee: Aluminum Company of America
    Inventors: Jan H. L. Van Linden, Michael J. Kionosz, James R. Bowser
  • Patent number: 4927459
    Abstract: Spent potlinings from aluminum reduction cells are fed to an aluminum reclamation furnace as a partial replacement for or supplement to the molten salt flux used in the reclamation process. This rids the spent potlinings of materials which would leach into soil or groundwater if the potlinings were otherwise disposed of at dumpsites, rendering them suitable for dumping with no hazard to the environment. Benefits to the reclamation process may be had at the same by substituting the less expensive potlinings for the salt flux materials and by using the fuel potential of the potlinings to reduce the external fuel requirement.
    Type: Grant
    Filed: March 17, 1989
    Date of Patent: May 22, 1990
    Assignee: Imco Recycling Inc.
    Inventors: Owen M. Gardner, Ralph L. Cheek