Patents by Inventor David W. Horsfall

David W. Horsfall 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).

  • Dense medium separation
    Patent number: 4169786
    Abstract: In a dense medium separation process a product of a separation step containing separated material and magnetic dense medium particles is passed through a sieve bend and the undersize only is treated for the magnetic recovery of the dense medium particles.
    Type: Grant
    Filed: November 17, 1977
    Date of Patent: October 2, 1979
    Inventor: David W. Horsfall
  • Dense medium separation
    Patent number: 4140628
    Abstract: A method for recovering magnetic dense medium particles from a suspension containing these particles and other less dense particles includes the steps of subjecting the suspension to at least a single stage high relative density separation to form a first fraction containing substantially only dense medium particles and a second fraction containing the bulk of the other particles and some dense medium particles, and subjecting the second fraction to a magnetic separation for recovery of the remaining dense medium particles. Each stage of the high relative density separation is effected in a cyclone. The suspension may be the overflow or the underflow from a dense medium process for the beneficiation of coal fines.
    Type: Grant
    Filed: June 28, 1977
    Date of Patent: February 20, 1979
    Inventor: David W. Horsfall