Patents Assigned to Sunds Defibrator Pori Oy
  • Production of prehydrolyzed pulp
    Patent number: 5589033
    Abstract: Processes for preparing pulp from lignin-containing cellulosic material are disclosed including a prehydrolysis step followed by neutralizing hydrolysate and the prehydrolyzed cellulosic material in the reactor with alkaline neutralizing liquor, removing the neutralized hydrolysate from the reactor and delignifying the neutralized prehydrolyzed cellulosic material with alkaline cooking liquor containing sodium sulfide and sodium hydroxide.
    Type: Grant
    Filed: May 13, 1994
    Date of Patent: December 31, 1996
    Assignee: Sunds Defibrator Pori OY
    Inventors: Panu Tikka, Kari Kovasin
  • Washer
    Patent number: 5460019
    Abstract: The invention concerns a drum washer. The washer has a shaft formed by two cones (46) placed with their bases against one another. The shaft can be used as a supporting structure for the drum. Vanes (48) can also be placed on it for assisting in collecting washing liquid falling from the upper part of the drum separately from the washing liquid ending up on the bottom of the drum. The washer is especially suitable for washing cellulose pulp.
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: October 24, 1995
    Assignee: Sunds Defibrator Pori Oy
    Inventors: Alpo Ojala, Seppo Rosnell
  • Drum washer
    Patent number: 5421176
    Abstract: The invention concerns a drum washer. The washer has two plates (14; 18) located after each other in parallel with the drum, and the pulp to be washed is conducted between these plates. Between the plates there is a gap (22) closed by a flap valve (25) by way of which gap washing liquid is conducted through the mat. The washer is especially suitable for washing cellulose pulp.
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: June 6, 1995
    Assignee: Sunds Defibrator Pori Oy
    Inventors: Alpo Ojala, Seppo Rosnell, Reima Karke