Patent ID: 8337669

Claim:
Apparatus for washing and dewatering pulp comprising first and second rotatable press rolls including permeable outer surfaces, and a casing comprising a vat in which said first and second rotatable press rolls are installed, said vat partially enclosing said permeable outer surfaces of each of said first and second rotatable press rolls and forming a gap between said vat and said permeable outer surfaces of said first and second rotatable press rolls, said first and second rotatable press rolls being juxtaposed with each other to provide a press nip therebetween for pressing said pulp therein, feed means for feeding said pulp to said gap in the direction of rotation of said first and second rotatable press rolls towards said press nip, said vat comprising at least one vat segment including a first side vat segment partially enclosing said permeable outer surface of said first rotatable press roll, a second side vat segment partially enclosing said permeable outer surface of said second rotatable press roll, and a central vat segment partially enclosing said permeable outer surface of said first and second rotatable press rolls between said press nip and said first and second side vat segments, thereby providing at least one compartment between said central vat segment and said casing, said casing comprising a first side casing member including said first side vat segment and a second side casing member including said second side vat segment, at least said first side casing member being pivotable about an axis of rotation and movable between a closed position and an open position providing access to said first rotatable press roll in said open position, and said first side casing member including at least one support member for supporting said central vat segment when said first side casing member is in said closed position, and pressure equalization means for equalizing the pressure between said at least one compartment and the pressure in said gap.