Patents by Inventor Erik I. Sandvik

Erik I. Sandvik 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).

  • Oil recovery using stabilized saline heat-treated heteropolysaccharide solutions
    Patent number: 4425246
    Abstract: A process for recovering crude oil from a subterranean formation using aqueous saline heteropolysaccharide solutions containing at least 0.5 wt. % of inorganic salts which are stabilized against viscosity loss on heat treatment. The stabilization process comprises preparing an aqueous solution containing heteropolysaccharide and inorganic salts, removing oxygen from the saline solution, heating to a temperature of at least 100.degree. C. in an inert atmosphere, then removing cell debris. The solutions also have improved filterability and are free of cell debris.
    Type: Grant
    Filed: September 18, 1981
    Date of Patent: January 10, 1984
    Assignee: Exxon Research & Engineering Co.
    Inventors: George M. Holzwarth, Lars A. Naslund, Erik I. Sandvik