# US 5,699,573 A · Method and pulp washing machine for washing of pulp or any corresponding material > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,699,573 A - Document ID: US5699573A - Status: Granted - Kind: A - Application number: 08/433,326 - Filed: 1995-06-30 - Granted: 1997-12-23 - Earliest claimed: 1992-11-05 - Assignees: Finbark Oy - Inventors: Timo Tapio Saalasti - Web page: https://patentgrep.com/patent/US5699573A ## CPC - D21C 9/02: Washing {; Displacing cooking or pulp-treating liquors contained in the pulp by fluids, e.g. wash water or other pulp-treating agents} - D21C 9/06: in filters {; Washing of concentrated pulp, e.g. pulp mats, on filtering surfaces} - D21D 1/40: Washing the fibres - D21C: PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR - D21D: TREATMENT OF THE MATERIALS BEFORE PASSING TO THE PAPER-MAKING MACHINE ## Abstract In the pulp washing machine and method therefor, pulp to be washed is fed between the rotating drum and the pressing roll inside it, so that pulp passes along a spiral-formed track around the pressing roll, being thereby pressed several times. Washing liquid is fed to the pulp at one or several points along its track of movement, between the pressings and/or at the pressing position. Washing thus takes place partly as a diffusion and partly as a displacement washing process. Washing is efficient and reduces the breaking of pulp fibers down to a minimum. ## Claims ### Claim 1 A method for washing pulp or any corresponding material, comprising the steps of: transporting the material to be washed between a rotating drum (1) and a rotating pressing roll (2) inside the drum, in a direction along a longitudinal axis of the drum from one end thereof, at least one of the drum and the pressing roll being perforated, pressing the material to be washed a plurality of times between the drum and the pressing roll during the transporting step, and wetting the material to be washed with washing liquid at least at one position during the transporting step. ### Claim 2 (depends on 1) The method according to claim 1, wherein the wetting occurs at a plurality of positions along the longitudinal axis. ### Claim 3 (depends on 2) The method according to claim 2, wherein the wetting step includes supplying the washing liquid by liquid feeding means (3) arranged within the drum (1). ### Claim 4 (depends on 2) The method according to claim 2, wherein the wetting step includes supplying the washing liquid from outside the drum (1) which is perforated or from within the roll (2) which is perforated. ### Claim 5 (depends on 1) The method according to claim 1, wherein the wetting step includes supplying the washing liquid by liquid feeding means (3) arranged within the drum (1). ### Claim 6 (depends on 1) The method according to claim 1, wherein the wetting step includes supplying the washing liquid from outside the drum (1) which is perforated or from within the pressing roll (2) which is perforated. ### Claim 7 (depends on 1) The method according to claim 1, wherein the transporting step includes moving the material to be washed using a plurality of screw parts (4) disposed radially outward about an outer peripheral portion of the pressing roll (2). ### Claim 8 (depends on 7) The method according to claim 7, wherein the wetting step includes supplying the washing liquid from a liquid feeding means, wherein said plurality of screw parts are integral to said liquid feeding means. ### Claim 9 (depends on 1) The method according to claim 1, wherein the transporting step includes tilting the drum downwards in the direction of the transport of the material to be washed. ### Claim 10 A pulp washing machine for washing pulp or any corresponding material, comprising a rotatable drum (1), a rotatable pressing roll (2) rotatably fitted within the rotating drum (1), at least one of the drum (1) and the pressing roll (2) being perforated, means for feeding material to be washed into the space between the drum and the pressing roll from an inlet to an outlet end of the drum, means for moving the pressing roll (2) towards an inner surface of the drum so as to provide a pressing point for the material between the drum (1) and the pressing roll (2), means within the space between the drum and the pressing roll for advancing the material, when the drum and pressing roll rotate, along a spiral-formed track structure extending around the pressing roll (2), from the inlet end of the drum to an outlet end thereof, and liquid feeding means (3;12) for feeding washing liquid onto the material to be washed in at least one position along said spiral formed track thereof. ### Claim 11 (depends on 10) The machine according to claim 10, wherein the liquid feeding means is adapted to supply washing liquid at several positions on the track of the material to be washed. ### Claim 12 (depends on 11) The machine according to claim 11, wherein the liquid feeding means (3) includes an elongated hollow structure extending within inside the drum (1), above the pressing roll (2), said structure having one or more discharge openings within the drum. ### Claim 13 (depends on 10) The machine according to claim 10, wherein said structure includes a plurality of solid screw parts (4) for transporting the material to be washed in a direction along an axis of the drum. ### Claim 14 (depends on 10) The machine according to claim 10, wherein the drum (1) and the pressing roll (2) are angled with respect to a horizontal line such that the inlet end is higher than the outlet end. ### Claim 15 (depends on 10) The machine according to claim 10, wherein the drum (1) and the pressing roll are angled with respect to a horizontal line such that the inlet end is lower than the outlet end. ### Claim 16 (depends on 10) The machine according to claim 10, wherein the outlet end of the drum (1) includes a cover plate (8) for limiting outflow therethrough. ### Claim 17 (depends on 10) The machine according to claim 10, wherein the drum (1) is partly submerged into the washing liquid.