Method and apparatus for mechanical defibration of wood
AssigneeMetso Paper, Inc.
InventorTomas Björkqvist
Life of this patent
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Abstract
A system for mechanical defibration of wood kneads the wood by moving a defibration surface having contours at least partly in contact with the wood in a direction at a speed in relation to the wood and fibres are separated from the wood. The contours of the defibration surface are at regular intervals in the direction that the speed and the regular intervals determine a cycle time-length that is 1 to 3 times a relaxation time of the wood.
Claims9
A method for mechanical defibration of wood, the method comprising kneading wood, and separating fibres from the wood by means of the contours of the defibration surfaces,
- wherein a regular contour of the defibration surface and a correct speed of the surface in relation to the wood to be treated provide a regular cycle time-length which is 1 to 3 times the relaxation time of the wood under the defibration conditions.
In a system of wood and an apparatus for mechanical defibration of the wood, the improvements wherein:
- the apparatus comprises a defibration surface in contact with the wood and means moving the defibration surface in a direction of a wave pattern thereon, whereby kneading the wood and separating fibres from the wood;
- tops of the wave pattern are located at regular intervals in the direction;
- the wave pattern is of sine wave type at least at leading portions in the direction;
- and
- a distance between the tops and a speed of the moving are such that a cycle time-length of the tops is 1 to 3 times the relaxation time of the wood.
In a system of wood and means for mechanical defibration of the wood wherein the wood is kneaded by moving a defibration surface having contours at least partly in contact with the wood in a direction at a speed in relation to the wood and fibres are separated from the wood, the improvements wherein:
- the contours of the defibration surface are at regular intervals in the direction;
- and
- the speed and the regular intervals determine a cycle time-length that is 1 to 3 times a relaxation time of the wood.
Dependencies are inferred from the claim text.