Patents by Inventor Pertti Haapamaki

Pertti Haapamaki 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: 6789285
    Abstract: A method of improving the efficiency of the multistage washing of pulp, wherein the initial washing of a given batch of pulp is carried out using a gradually diluted, recovered filtrate fraction originating from the washing of the preceding batch of pulp as the washing liquid, prior to the final washing of the pulp batch. In the method, the recovered fraction filtrate is kept stored in such a way that the concentration gradient of dissolved substances is maintained until the fraction is used for washing the following batch of pulp. A further object of the invention is a pulp washing plant, wherein the method according to the invention is carried out in a laboratory-scale test washer and applied to industrial pulp washing plant solutions.
    Type: Grant
    Filed: January 17, 2002
    Date of Patent: September 14, 2004
    Assignee: Metso Paper Pori Oy
    Inventor: Pertti Haapamäki
  • Patent number: 5051195
    Abstract: Method and equipment for filtration of a suspension so that the suspension to be filtered is fed from a feed part (4) onto the filter face of a filter member (5), which moves relative the feed part. The pulp layer is formed on the outer face of the filter member and the filtrate flows into the interior of the filter member, and the pulp layer is removed from the filter member at the removing point. After the pulp removing point (17), before the feed point (4), one or several cleaning points (12) are provided wherein liquid is made to flow through the filter member (5) from the inner face of the filter member to the outer face. The flow rate of the liquid that flows through the cleaning point or points is adjusted higher than the rate of any liquid flow that may flow through the rest of the filter member from the inside-face side to the outside-face side.
    Type: Grant
    Filed: October 13, 1989
    Date of Patent: September 24, 1991
    Assignee: Sunds Defibrator Rauma Oy
    Inventors: Pertti Haapamaki, Aaro Ahlgren, Lassi Suoninen, Juho Eriksson
  • Patent number: 4664749
    Abstract: Method for the washing of chemical pulp (1) by means of a fourdrinier wire machine in two or more stages (6,10; 6',10'; 6", 10"; 6'", 10'") while the pulp web runs on the wire (3). The liquid contained in the pulp web is displaced by a washing liquid. The pulp web and the wire (3) run, during the washing, as submerged in the washing liquid while the washing liquid flows through the pulp web and the wire. One embodiment comprises passing the washing liquid upwardly through the pulp and then downwardly through the pulp.
    Type: Grant
    Filed: July 6, 1984
    Date of Patent: May 12, 1987
    Assignee: Rauma-Repola Oy
    Inventors: Pertti Haapamaki, Alpo Tuomi
  • Patent number: 4344321
    Abstract: An apparatus and method is disclosed for experimental displacement of liquids in slurries for measuring filtration rate, washing performance and displacement bleaching in pulp. An open top cylinder is movable to a vertical orientation and has a piston slidably positioned therein. The piston includes a porous face with communicating passages to its rear surface. Apparatus are provided for registering pressure in the cylinder as well as for providing regulated motion of the piston. Also, a valve is provided for admitting wash water to the lower part of the cylinder for back washing the filter cake.
    Type: Grant
    Filed: August 4, 1980
    Date of Patent: August 17, 1982
    Assignee: Rauma-Repola Oy
    Inventor: Pertti Haapamaki