Patents by Inventor Fredrick K. Lesan

Fredrick K. Lesan 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).

  • High recovery spiral wound membrane element
    Patent number: 4855058
    Abstract: This invention is a spiral wound membrane filtration element for reverse osmosis, ultrafiltration, microfiltration and filtration of gas mixtures and having a novel radial feed-concentrate flow path and axial permeate discharge allowing conversion of a feed mixture to be varied to any practical desired degree without regard to the membrane elements length while maitaining turbulent or chopped laminar hydrodynamic flow conditions where desired, and a method of using said membrane elements in a filtration process.
    Type: Grant
    Filed: May 2, 1988
    Date of Patent: August 8, 1989
    Assignee: Hydranautics
    Inventors: Eric C. Holland, Fredrick K. Lesan, Peter H. Knappe