A method and a liquor filter, in which liquor filter sealing medium is fed via a sealing medium channel (3) into an innermost sealing zone formed by an innermost sealing member (1), an outer seal (2) and the space between them at a causticizing plant of a chemical pulp mill. The sealing medium used is an alkaline sealing liquid and/or gas, which does not substantially dilute the liquor being filtered. Advantageously the sealing medium is filtrate from the liquor filter and/or gas taken from the interior of the liquor filter.

A method and a liquor filter, in which liquor filter sealing medium is fed via a sealing medium channel (3) into an innermost sealing zone formed by an innermost sealing member (1), an outer seal (2) and the space between them at a causticizing plant of a chemical pulp mill. The sealing medium used is an alkaline sealing liquid and/or gas, which does not substantially dilute the liquor being filtered. Advantageously the sealing medium is filtrate from the liquor filter and/or gas taken from the interior of the liquor filter.

A method of and an arrangement for introducing fiber suspension or pulp from a pulp vessel to a washing and/or filtering apparatus is based on simultaneous division and degassing of pulp at immediately upstream of the washing and/or filtering apparatus.

A method of and an arrangement for introducing fiber suspension or pulp from a pulp vessel to a washing and/or filtering apparatus is based on simultaneous division and degassing of pulp at immediately upstream of the washing and/or filtering apparatus.

In a rotary drum for thickening pulp, the rotary drum may include drainage channels for delivering filtrate from a pulp mat on the rotary drum to a filtrate chamber at an end of the rotary drum, and includes a flat face valve and plenum chamber assembly in the filtrate chamber. The flat face valve can be juxtaposed against drainage outlets of the drainage channels, wherein the flat face valve does not block the drainage outlets during a majority of the rotation of the rotary drum. An opening on the flat face valve may extend through the front surface and be aligned with the drainage outlets to provide a fluid passage through the flat face valve and to a plenum chamber behind the flat face valve such that air in the filtrate is collected in the upper portion of the plenum chamber and removed from the rotary drum.

In a rotary drum for thickening pulp, the rotary drum may include drainage channels for delivering filtrate from a pulp mat on the rotary drum to a filtrate chamber at an end of the rotary drum, and includes a flat face valve and plenum chamber assembly in the filtrate chamber. The flat face valve can be juxtaposed against drainage outlets of the drainage channels, wherein the flat face valve does not block the drainage outlets during a majority of the rotation of the rotary drum. An opening on the flat face valve may extend through the front surface and be aligned with the drainage outlets to provide a fluid passage through the flat face valve and to a plenum chamber behind the flat face valve such that air in the filtrate is collected in the upper portion of the plenum chamber and removed from the rotary drum.

Apparatus for washing and/or dewatering cellulose pulp is disclosed including a movable permeable surface in a pulp transportation chamber having a chamber gap above the movable permeable surface, a pulp distributor for distributing pulp onto the movable permeable surface, a throttle having a throttle gap width and an adjustable throttle adjuster to remotely adjust the throttle gap width so that a volume of pulp flow into the pulp distributor is equal to or greater than the volume of pulp flow out of the distributor during operation.

Apparatus for washing and/or dewatering cellulose pulp is disclosed including a movable permeable surface in a pulp transportation chamber having a chamber gap above the movable permeable surface, a pulp distributor for distributing pulp onto the movable permeable surface, a throttle having a throttle gap width and an adjustable throttle adjuster to remotely adjust the throttle gap width so that a volume of pulp flow into the pulp distributor is equal to or greater than the volume of pulp flow out of the distributor during operation.

A rotary drum for thickening pulp from a slurry, the drum including drainage channels delivering filtrate from a pulp mat on an outer surface of the rotary drum to at least one filtrate chamber at an end of the rotary drum, a flat face valve and plenum chamber assembly in the filtrate chamber. The flat face valve juxtaposed against drainage outlets of the drainage channels, wherein the flat face valve does not block the drainage outlets during a majority of the rotation of the rotary drum. At least one opening on the flat face valve extending through the front surface and aligned with the drainage outlets to provide a fluid passage through the flat face valve and to a plenum chamber behind the flat face valve such that air in the filtrate is collected in the upper portion of the plenum chamber and removed from the rotary drum.

A rotary drum for thickening pulp from a slurry, the drum including drainage channels delivering filtrate from a pulp mat on an outer surface of the rotary drum to at least one filtrate chamber at an end of the rotary drum, a flat face valve and plenum chamber assembly in the filtrate chamber. The flat face valve juxtaposed against drainage outlets of the drainage channels, wherein the flat face valve does not block the drainage outlets during a majority of the rotation of the rotary drum. At least one opening on the flat face valve extending through the front surface and aligned with the drainage outlets to provide a fluid passage through the flat face valve and to a plenum chamber behind the flat face valve such that air in the filtrate is collected in the upper portion of the plenum chamber and removed from the rotary drum.