Patents by Inventor Alfred E. Backstrom

Alfred E. Backstrom 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: 4035282
    Abstract: An improved method for recovery of bitumen form bituminous froth is disclosed having particular application in hot water separation of tar sands wherein comminuted tar sand is slurried in hot water, subject to gravity separation to isolate a bituminous froth, containing water and mineral matter, and the bituminous froth is diluted with a liquid hydrocarbon solvent and subject to a two-stage centrifugation to recover the substanitally water and mineral-free bitumen. In this improved process, the dilution of bituminous froth with liquid hydrocarbon solvent is staged such that no more than about 90% of the total hydrocarbon solvent is added to the bituminous froth prior to the first centrifuging stage and the remaining hydrocarbon solvent is added prior to the second centrifuging stage.
    Type: Grant
    Filed: August 20, 1975
    Date of Patent: July 12, 1977
    Assignees: Shell Canada Limited, Shell Explorer Limited
    Inventors: Frederick C. Stuchberry, Alfred E. Backstrom