Patent ID: 8092653

Claim:
A press roll having a first end and a second end for washing pulp comprising a central drum, at least one perforated roll plate providing a mantle covering said central drum, a plurality of first chambers extending longitudinally along said press roll between said central drum and said at least one perforated roll plate, a plurality of second chambers extending longitudinally along said press roll between said central drum and said at least one perforated roll plate, said pluralities of first and second chambers being paired with each other around a periphery of said press roll, each of said plurality of first chambers including an inlet defining a substantially radial flow path thereinto, an outlet at said first end of said press roll, and a substantially continuous first flow channel between said inlet and said outlet, each of said plurality of second chambers including an inlet defining a substantially tangential flow path thereinto, an outlet at said second end of said press roll, and a substantially continuous second flow channel extending between said inlet and said outlet, said plurality of first chambers being closed at said second end preventing liquid from being discharged therefrom, and said plurality of second chambers being closed at said first end preventing liquid from being discharged therefrom, whereby the direction of said flow within said substantially continuous first flow channel is opposite to the direction of said flow within said substantially continuous second flow channel.