Patents by Inventor Lennart Hagelquist

Lennart Hagelquist 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 of integrating bleaching and recovery in the production of pulp
    Patent number: 5540816
    Abstract: A method of integrating bleaching and recovery in connection with the production of chemical pulp that has been digested and preferably delignified with oxygen gas using processes that retain the viscosity and strength, to kappa number less than 16 without the use of chemicals containing chlorine, and using a bleaching sequence including at least one step with sequestering agent and/or acid, and a peroxide step.
    Type: Grant
    Filed: April 8, 1994
    Date of Patent: July 30, 1996
    Assignee: Kvaerner Pulping Technologies AB
    Inventors: Stig Andtbacka, Anders Bergqvist, Lennart Hagelquist, Daniel P.ang.lsson, Gunnar Wernqvist