Patents by Inventor Alf Aspvik

Alf Aspvik 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).

  • Method and apparatus for optimizing the liquor-to-wood ratio during the production of paper pulp
    Patent number: 5679217
    Abstract: Provided is a method and apparatus which decreases a liquor--to--wood ratio at the top of a continuous digester while increasing a liquor--to--wood ratio in the upstream pre-impregnation vessel. A substantially wood-chip free liquor portion is drawn from the top of the digester through a heater to the bottom of the pre-impregnation vessel through a return conduit. A stream is drawn off the return conduit, upstream of the heater, for transfer to the top of the vessel without mixing with wool chips.
    Type: Grant
    Filed: February 3, 1995
    Date of Patent: October 21, 1997
    Assignee: Kvaerner Pulping AB
    Inventors: Peter Outzen, Staffan Berg, Alf Aspvik