Fractional Crystallization Patents (Class 75/679)
  • Patent number: 8313554
    Abstract: A method for the separation of a dispersion of molten aluminium and solid inclusions formed from a melt of aluminium containing one or more foreign chemical elements. Molten aluminium surrounding the solid inclusions is at least essentially replaced by a molten salt.
    Type: Grant
    Filed: June 20, 2007
    Date of Patent: November 20, 2012
    Assignee: Aleris Switzerland GmbH
    Inventors: Paul Alexander De Vries, Huibrecht Adriaan Wouters, Marcellus Albertus Hogenboom
  • Patent number: 8202347
    Abstract: A manufacturing process for a remelt block containing aluminum designed for making aluminum alloy for the aircraft industry in which scrap containing mainly aluminum alloys used in the aircraft industry is supplied during a supply stage, the scrap is melted in a smelting furnace in order to obtain an initial molten metal bath during a smelting stage, the initial molten metal bath is subjected to purification by fractional crystallization in order to obtain a solidified mass and a bath of residual liquid during a segregation stage, and the solidified mass is recovered in order to obtain a remelt block during a recovery stage. The invention is particularly useful for the recycling of aluminum alloys used in the aircraft industry as it makes it possible to purify scrap of series 2XXX or series 7XXX alloys for iron and silicon, without eliminating additive elements such as zinc, copper and magnesium.
    Type: Grant
    Filed: June 18, 2007
    Date of Patent: June 19, 2012
    Assignee: Constellium France
    Inventors: Jean-Francois Verdier, Jean-Remi Butruille, Michel Leroy, Didier Valax
  • Patent number: 7955414
    Abstract: A method and device for the purification and separation of purified metal from a metal mother liquid having a specific density and comprising one or more foreign element(s). The method includes: providing in a column device a starting material including metal crystals and a metal mother liquid including at least one foreign element; applying a temperature difference between a relatively hot zone at the upper end of the column and a relatively cool zone at the lower end of the column; a separation step wherein at least a part of the metal crystals is separated from the metal mother liquid by rising of the metal crystals to the upper surface of the metal mother liquid; and a further separation step wherein purified metal floating on the upper surface of the metal mother liquid is discharged from the column device.
    Type: Grant
    Filed: July 5, 2007
    Date of Patent: June 7, 2011
    Assignee: Aleris Switzerland GmbH
    Inventors: Huibrecht Adriaan Wouters, Andreas Ten Cate, Elisabeth Maria Beunder, Willem Boender, Marcellus Albertus Hogenboom, René Kieft, Joost Christiaan Storm
  • Patent number: 7892318
    Abstract: Method for purifying molten metal having a specific density and including one or more foreign elements to be removed, by (a) cooling the molten metal to a eutectic temperature to simultaneously form purified metal crystals and crystals including at least one foreign element, and (b) separating at least some of the purified metal crystals from the crystals including at least one foreign element by adjusting the molten metal specific density within a range delimited by a lower value being specific density of the purified metal crystals and an upper limit being specific density of the crystals including the at least one foreign element. The molten metal specific density is adjusted to this range by addition of a metal to alter the molten metal specific density and maintained within this range during separation. The method is advantageously applicable for purification of aluminium melts from recycle aluminium and aluminium scraps.
    Type: Grant
    Filed: June 8, 2007
    Date of Patent: February 22, 2011
    Assignee: Aleris Switzerland GmbH c/o K+P Treuhandgesellschaft
    Inventors: Huibrecht Adriaan Wouters, Andreas Ten Cate, Elisabeth Maria Beunder, Willem Boender, Marcellus Albertus Hogenboom, René Kieft, Joost Christiaan Storm
  • Publication number: 20100024602
    Abstract: Method for purifying molten metal having a specific density and including one or more foreign elements to be removed, by (a) cooling the molten metal to a eutectic temperature to simultaneously form purified metal crystals and crystals including at least one foreign element, and (b) separating at least some of the purified metal crystals from the crystals including at least one foreign element by adjusting the molten metal specific density within a range delimited by a lower value being specific density of the purified metal crystals and an upper limit being specific density of the crystals including the at least one foreign element. The molten metal specific density is adjusted to this range by addition of a metal to alter the molten metal specific density and maintained within this range during separation. The method is advantageously applicable for purification of aluminium melts from recycle aluminium and aluminium scraps.
    Type: Application
    Filed: June 8, 2007
    Publication date: February 4, 2010
    Applicant: ALERIS SWITZWERLAND GMBH
    Inventors: Huibrecht Adriaan Wouters, Andreas Ten Cate, Elisabeth Maria Beunder, Willem Boender, Marcellus Albertus Hogenboom, Rene Kieft, Joost Christiaan Storm
  • Patent number: 7648559
    Abstract: The invention relates to a method for fractional crystallization of an at most partially solidified molten metal, in which a layer of at most partially solidified molten metal having an upper surface and a lower surface is divided into a series of compartments communicating with each other, in which the metal is stirred in at least some of the compartments, and in which crystals formed and/or existing in the layer of metal are selectively transported in a predetermined direction and molten metal is selectively transported in the opposite direction.
    Type: Grant
    Filed: June 27, 2003
    Date of Patent: January 19, 2010
    Assignee: Aleris Switzerland GmbH c/o K+P Treuhangesellschaft
    Inventors: Paul Alexander De Vries, Huibrecht Adriaan Wouters
  • Patent number: 7537639
    Abstract: Method of cooling an at most partially solidified molten metal during fractional crystallization wherein metal crystals formed have a purer composition than that of the molten metal. Salt in solid form is used to cool the at most partially solidified molten metal.
    Type: Grant
    Filed: November 10, 2004
    Date of Patent: May 26, 2009
    Assignee: Aleris Switzerland GmbH
    Inventors: Paul Alexander De Vries, Huibrecht Adriaan Wouters, Martinus Leonardus Rutten, Volker Gerhard Aurich, Johannes Hendrikus Ten Have
  • Patent number: 7531023
    Abstract: The invention relates to a method for the purification of a molten metal containing one or more foreign elements. The molten metal is cooled to a eutectic temperature to simultaneously form purified metal crystals and crystals containing at least one foreign element, and at least some of the crystals containing at least one foreign element are separated from the purified metal crystals by using a solid-solid separation technique.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: May 12, 2009
    Assignee: Aleris Switzerland GmbH
    Inventor: Paul Alexander De Vries
  • Patent number: 7419530
    Abstract: The invention relates to a method for fractional crystallization of an at most partially solidified molten metal. According to the invention a layer of at most partially solidified molten metal to be crystallized is cooled by a layer of cooling liquid, which is present above and/or below the layer of at most partially solidified molten metal so as to crystallize the molten metal.
    Type: Grant
    Filed: June 27, 2003
    Date of Patent: September 2, 2008
    Assignee: Aleris Switzerland GmbH c/o K+P Treuhangesellschaft
    Inventors: Paul Alexander De Vries, Huibrecht Adriaan Wouters
  • Patent number: 6406515
    Abstract: An aluminum bloom more than 99.95% pure is obtained by segregation of aluminum from an impure parent liquor. Heat supplied to the parent liquor during growth of the bloom is adjusted as a function of the height of the bloom.
    Type: Grant
    Filed: July 5, 2001
    Date of Patent: June 18, 2002
    Assignee: Aluminium Pechiney
    Inventor: Michel Leroy
  • Patent number: 6398845
    Abstract: A method for purifying aluminum to provided which comprises the steps of maintaining aluminum as a starting material in a molten condition in N+1 vessels; wherein N+1 vessels for molten aluminum and N cooling bodies are provided which are immersed in molten aluminum in the vessels and upon which highly purified aluminum is crystallized on the surfaces thereof. The N+1 vessels are arranged sequentially from 1-st to (N+1)-th and the N cooling bodies are sequentially arranged from 1-st to N-th, respectively, and the vessels and cooling bodies are moved relative to each other.
    Type: Grant
    Filed: May 30, 2000
    Date of Patent: June 4, 2002
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Hiroshi Tabuchi, Ichiro Tanaka, Akihiko Takahashi, Hidemitsu Shimizu
  • Patent number: 6156095
    Abstract: The present invention provides a method for producing high purity aluminum by immersing a cooling body in molten aluminum, and forming and growing crystals of the high purity aluminum on the cooling body by rotating the cooling body and introducing bubbles of a gas into the rotating molten aluminum by the rotation of the cooling body.
    Type: Grant
    Filed: August 6, 1998
    Date of Patent: December 5, 2000
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Ichiro Tanaka, Hiroshi Tabuchi, Akihiko Takahashi
  • Patent number: 6156092
    Abstract: The present invention provides a method for producing high purity aluminum by immersing a cooling body in molten aluminum, and forming and growing crystals of the high purity aluminum on the cooling body by rotating the molten aluminum around the cooling body and introducing bubbles of a gas into the rotating molten aluminum.
    Type: Grant
    Filed: August 6, 1998
    Date of Patent: December 5, 2000
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Ichiro Tanaka, Hiroshi Tabuchi, Akihiko Takahashi
  • Patent number: 5573574
    Abstract: A process for obtaining aluminum of purity above 99.998%. A liquid aluminum raw material is subjected to a fractional crystallization to obtain prepurified aluminum crystals in a yield of between 50 and 80% and a liquid aluminum portion of lesser purity. The prepurified aluminum crystals are subjected to a three-layer electrolysis process in which the uppermost layer comprises a cathodic purified aluminum layer. The aluminum of purity above 99.998% is removed from the uppermost layer at a yield of above 90%, the aluminum having a total rare earth content of less than 100 ppb and a total content of U+Th of less than 20 ppb.
    Type: Grant
    Filed: June 13, 1995
    Date of Patent: November 12, 1996
    Assignee: Aluminium Pechiney
    Inventor: Michel Leroy
  • Patent number: 5110352
    Abstract: An aluminum material for use as an electronic material is produced by a method comprising the steps of melting aluminum inevitably containing U and Th to obtain molten aluminum, holding the molten aluminum heated at a temperature above the solidification temperature thereof, and immersing a hollow rotary cooling member in the molten aluminum and rotating the cooling member in the molten aluminum while maintaining the surface of the cooling member at a temperature lower than the solidification temperature by supplying a cooling fluid to the interior of the cooling member to cause aluminum to crystallize out on the surface of the cooling member with reduced U and Th contents.
    Type: Grant
    Filed: May 24, 1991
    Date of Patent: May 5, 1992
    Assignee: Showa Aluminum Corporation
    Inventors: Kazuo Toyoda, Masao Maeda