Patents by Inventor Hendrik Kruidhof

Hendrik Kruidhof 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: 6632360
    Abstract: A device for separating liquid and/or gas components from each other, which device includes a ceramic membrane comprising a porous layer of &ggr;-alumina which is present on top of a porous layer of supporting material, wherein an alkali-free, phosphorous material is provided between said supporting material and said layer of &ggr;-alumina, and wherein said material preferably consists of monoaluminium phosphate.
    Type: Grant
    Filed: May 11, 2001
    Date of Patent: October 14, 2003
    Assignee: Universiteit Twente
    Inventors: Arian Nijmeijer, Hendrik Kruidhof, Hendrik Verweij
  • Patent number: 5993503
    Abstract: The invention relates to a method for dephosphorizing manure, in particular pig manure, comprising of causing phosphate to dissolve, which phosphate is present at least partially in the form of phytate in the manure, separating the manure into a solid and a liquid fraction and removing the phosphate from the liquid fraction of the manure.Causing phosphate to dissolve can be achieved in different ways, for instance by storing the manure for a predetermined period of time under conditioned circumstances, or by sustaining a continuous movement of the manure at a temperature of at least 15.degree. C., preferably between 20 and 40.degree. C., to allow free escape therefrom of formed gases, or by the presence of means for complexing divalent ions, or by the enzymatic decomposition of phytate present in the manure. The phosphate is preferably removed from the liquid fraction by causing struvite to be precipitated therefrom.
    Type: Grant
    Filed: September 14, 1995
    Date of Patent: November 30, 1999
    Assignee: Ceres Milieu Holding B.V.
    Inventor: Hendrik Kruidhof