Patents by Inventor Freerk J. Fontein

Freerk J. Fontein 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: 4202762
    Abstract: Waste water containing suspended biologically active sludge and circulating in an endless path in a vessel is aerated by withdrawing a stream of the water and recycling it to the vessel in the form of a plurality of downwardly directed jets which penetrate the water surface and thereby entrain air in the water. The jets are directed onto the water surface at an angle of less than 60.degree. and the horizontal component of the motion of the jets is substantially parallel to the recirculation path of the main body of water at the point of impact. The jets are divided regularly over the water surface of the vessel and the energy being imparted to the total number of water jets being at least 2 W per m.sup.3 of water contained in the vessel.
    Type: Grant
    Filed: December 15, 1978
    Date of Patent: May 13, 1980
    Assignee: Stamicarbon, B.V.
    Inventors: Freerk J. Fontein, Hubertus F. Jennekens
  • Patent number: 4189384
    Abstract: A method and apparatus for aerating a body of waste water in which air is supplied to a bell chamber disposed below the surface of the water and in which a stream of water is withdrawn from the body and jetted through the air space in the chamber so as to penetrate the water residing below the chamber and thereby drive air into the water.
    Type: Grant
    Filed: April 24, 1975
    Date of Patent: February 19, 1980
    Assignee: Stamicarbon, B.V.
    Inventors: Freerk J. Fontein, Hubertus F. Jennekens
  • Patent number: 4034861
    Abstract: A process and apparatus for recovering useable materials from discarded scrap material, such as junked automobiles, is disclosed in which non-ferrous metals are separated from non-metals in a hydrocyclone using water as the aqueous separating medium. A particulate scrap/water suspension is injected into the cylindrical area of the hydrocyclone and a predominently non-metal-containing portion is removed from an overflow area of the cyclone while the non-ferrous metal containing portion is removed from the apex area of the cyclone. If required, the scrap material is preferably pulverized prior to treatment and is subjected to a ferrometallic separation operation if such metals are present.
    Type: Grant
    Filed: December 12, 1975
    Date of Patent: July 12, 1977
    Assignee: Stamicarbon B.V.
    Inventors: Freerk J. Fontein, Hubert H. Dreissen