Patents by Inventor David J. Roha

David J. Roha has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7819937
    Abstract: An agglomerate comprising alumina, carbon, and a binder for use in a vapor recovery reactor of a carbothermic alumina reduction furnace is disclosed. A method for using alumina-carbon agglomerates to capture aluminum vapor species and utilize waste heat from off-gases in a vapor recovery reactor to form a recyclable material is also disclosed.
    Type: Grant
    Filed: January 7, 2010
    Date of Patent: October 26, 2010
    Assignees: Alcoa Inc., Elkem AS
    Inventors: Richard J. Fruehan, David J. Roha, Anders Schei, Mark L. Weaver
  • Patent number: 7753988
    Abstract: An agglomerate comprising alumina, carbon, and a binder for use in a vapor recovery reactor of a carbothermic alumina reduction furnace is disclosed. A method for using alumina-carbon agglomerates to capture aluminum vapor species and utilize waste heat from off-gases in a vapor recovery reactor to form a recyclable material is also disclosed.
    Type: Grant
    Filed: July 9, 2007
    Date of Patent: July 13, 2010
    Assignees: Alcoa Inc., Elkem AS
    Inventors: Richard J. Fruehan, David J. Roha, Anders Schei, Mark L. Weaver
  • Publication number: 20100107815
    Abstract: An agglomerate comprising alumina, carbon, and a binder for use in a vapor recovery reactor of a carbothermic alumina reduction furnace is disclosed. A method for using alumina-carbon agglomerates to capture aluminum vapor species and utilize waste heat from off-gases in a vapor recovery reactor to form a recyclable material is also disclosed.
    Type: Application
    Filed: January 7, 2010
    Publication date: May 6, 2010
    Applicant: Alcoa Inc.
    Inventors: Richard J. Fruehan, David J. Roha, Anders Schei, Mark L. Weaver
  • Publication number: 20090013823
    Abstract: An agglomerate comprising alumina, carbon, and a binder for use in a vapor recovery reactor of a carbothermic alumina reduction furnace is disclosed. A method for using alumina-carbon agglomerates to capture aluminum vapor species and utilize waste heat from off-gases in a vapor recovery reactor to form a recyclable material is also disclosed.
    Type: Application
    Filed: July 9, 2007
    Publication date: January 15, 2009
    Applicant: Alcoa Inc.
    Inventors: Richard J. Fruehan, David J. Roha, Anders Schei, Mark L. Weaver
  • Patent number: 7267158
    Abstract: A method of producing aluminum castings which includes the steps of casting a molten alloy, contacting the surface of the molten alloy with a humidified atmosphere and solidifying the alloy. The method is particularly suited for aluminum-magnesium alloys such as AA 5XXX and 7XXX series alloys. In addition to reducing the thickness of the surface oxide layer formed during casting, the method also provides improved surface quality of cast products and reduces subsequent remedial re-work or scalping. An improved aluminum-magnesium cast alloy product is also disclosed.
    Type: Grant
    Filed: July 2, 2003
    Date of Patent: September 11, 2007
    Assignee: Alcoa Inc.
    Inventors: Paula L. Kolek, David H. DeYoung, David J. Roha, Patricia A. Stewart, Michael A. Easley, Jorge A. Ramos Cruz, Larry F. Wieserman
  • Publication number: 20040163967
    Abstract: Inert anodes useful in electrolytic aluminum production cells are disclosed. The inert anodes have sloped bottom surfaces with controlled bubble release angles. In one embodiment, the bottom surface is substantially conical with a bubble release angle of up to 30 degrees. The cross-sectional size of the inert anodes is also controlled in order to maximize efficiency of the cells. The inert anodes may be provided in arrays in aluminum production cells in order to achieve commercial cell currents.
    Type: Application
    Filed: February 20, 2003
    Publication date: August 26, 2004
    Inventors: Alfred F. LaCamera, Xinghua Liu, David J. Roha, James T. Burg, Robert L. Kozarek
  • 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