Abstract: An apparatus for fiberizing and screening of fibrous material, which comprises of a rotating drum (1) the drum wall (2) of which consists of a non-perforated (7) and a perforated (8) part. The non-perforated part in the inlet end of the drum is separated from the perforated part in the outlet end of the drum by means of a partition wall (9) having an opening (10). The height (h) of the partition wall varies so that a periodical overflow is achieved when the drum rotates.

Abstract: A process for washing fibre stock. The fibre stock is described is passed along a passage 14 from a stock inlet 15 to a stock outlet 16. The passage is defined by a portion of the inner surface of a substantially horizontal cylindrical screen 4, preferably a wire gauze. Washing liquid such as water is introduced into the passage, preferably by means of apertures 9 in a longitudinally extending hollow member 8. Effluent liquid passes through the screen, for extraction e.g. through outlets 24 and 25.To enable the washing of stock of high consistency e.g. up to 8%, while avoiding plugging of the screen 4, the arrangement is such that the stock only partially fills the cylindrical screen and is subjected to a tumbling action by the rotary movement of the cylindrical screen as the stock moves along the passage 14 to the stock outlet 16. The hollow member 8 is displaced downwardly from the axis of the cylindrical screen, so as to be positioned within the tumbling stock.

Abstract: A process and apparatus for washing fibre stock. The fibre stock is passed along a passage 14 from a stock inlet 15 to a stock outlet 16. The passage is defined by a portion of the inner surface of a substantially horizontal cylindrical screen 4, preferably a wire gauze. Washing liquid such as water is introduced into the passage, preferably by means of apertures 9 in a longitudinally extending hollow member 8. Effluent liquid passes through the screen, for extraction e.g. through outlets 24 and 25. To enable the washing of stock of high consistency e.g. up to 8%, while avoiding plugging of the screen 4, the arrangement is such that the stock only partially fills the cylindrical screen and is subjected to a tumbling action by the rotary movement of the cylindrical screen as the stock moves along the passage 14 to the stock outlet 16. The hollow member 8 is displaced downwardly from the axis of the cylindrical screen, so as to be positioned within the tumbling stock.

Abstract: The disclosure describes a method and a device for pumping fiber suspensions of high consistency. Shear forces disrupting fiber flocs are induced near the front edge of the vanes of the impeller in a centrifugal pump which fluidize the fiber suspension hereby converting it into an easily pumpable state. This is effected by an inlet part having recesses and/or lobes in its inner surface in front of the impeller which cooperate with a rotor having an outer surface in which there are recesses and/or lobes disposed into the inlet part.