Patents by Inventor Christopher C. Dell

Christopher C. Dell 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).

  • Countercurrent decantation
    Patent number: 4174281
    Abstract: In countercurrent decantation, upwardly flowing liquid is treated with downwardly falling solids in a progressive series of vertically stacked treatment cells. Solids fall through a valve from one cell to the next. The valve is a buoyant sphere which will sink, to open, under a weight of solids, but the valve is sufficiently buoyant to close when there is still enough solid queuing thereon to prevent liquid from passing through it.
    Type: Grant
    Filed: May 1, 1978
    Date of Patent: November 13, 1979
    Assignee: National Research Development Corporation
    Inventor: Christopher C. Dell
  • Froth flotation
    Patent number: 4165279
    Abstract: Apparatus for use in froth flotation comprising at least four parallel upright partition walls defining flotation columns within a receptacle. Below each partition wall is a froth generator driven by a shaft passing through the thickness of the partition wall. Rods of differential buoyancies divide each flotation column into flotation cells in such a way as to permit froth to pass upwardly from one cell to another in a controlled manner maintaining a predetermined froth thickness in each cell.
    Type: Grant
    Filed: December 27, 1977
    Date of Patent: August 21, 1979
    Assignee: National Research Development Corporation
    Inventor: Christopher C. Dell
  • Countercurrent decantation
    Patent number: RE31374
    Abstract: In countercurrent decantation, upwardly flowing liquid is treated with downwardly falling solids in a progressive series of vertically stacked treatment cells. Solids fall through a valve from one cell to the next. The valve is a buoyant sphere which will sink, to open, under a weight of solids, but the valve is sufficiently buoyant to close when there is still enough solid queuing thereon to prevent liquid from passing through it.
    Type: Grant
    Filed: July 10, 1981
    Date of Patent: September 6, 1983
    Assignee: National Research Development Corporation
    Inventor: Christopher C. Dell