Patents by Inventor Tor Lindstad

Tor Lindstad 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).

  • Method for recovering aluminum vapor and aluminum suboxide from off-gases during production of aluminum by carbothermic reduction of alumina
    Patent number: 6530970
    Abstract: A method for aluminum recovery during the carbothermic production of aluminum in a smelting furnace (1,2) is disclosed, where during carbothermic reduction of alumina, aluminum and aluminum suboxide vapors are produced (3, 4), which are reacting with carbon. Reactive carbon is generated in situ by the cracking of hydrocarbon compounds (6) in a separate closed reactor vessel (5) at a temperature greater than about 1955° C. Solid aluminum carbide that formed during the reaction can then be recycled by a conduit (8) to the primary reactor for reduction to aluminum, and reactor gas (10) can be fed to a cooler (9).
    Type: Grant
    Filed: May 21, 2001
    Date of Patent: March 11, 2003
    Assignees: Alcoa Inc., Elkem ASA
    Inventor: Tor Lindstad
  • Method for recovering aluminum vapor and aluminum suboxide from off-gases during production of aluminum by carbothermic reduction of alumina
    Publication number: 20020170387
    Abstract: A method for aluminum recovery during the carbothermic production of aluminum in a smelting furnace (1,2) is disclosed, where during carbothermic reduction of alumina, aluminum and aluminum suboxide vapors are produced (3, 4), which are reacting with carbon. Reactive carbon is generated in situ by the cracking of hydrocarbon compounds (6) in a separate closed reactor vessel (5) at a temperature greater than about 1955° C. Solid aluminum carbide that formed during the reaction can then be recycled by a conduit (8) to the primary reactor for reduction to aluminum, and reactor gas (10) can be fed to a cooler (9).
    Type: Application
    Filed: May 21, 2001
    Publication date: November 21, 2002
    Inventor: Tor Lindstad
  • Thermal treatment of leaching residue from hydrometallurgical zinc production
    Patent number: 4072503
    Abstract: Pyrometallurgical process for recovering lead, zinc and precious metals from leaching residues and precipitates occuring during the hydrometallurgical production of zinc, comprising a weak oxydizing and reducing treatment of the starting material.
    Type: Grant
    Filed: March 19, 1975
    Date of Patent: February 7, 1978
    Assignee: Det Norske Zinkkompani A/S
    Inventors: Stig A. Peterson, Tor Lindstad, Froystein Dyvik, Georg Steintveit