Process for making wood chips
AssigneeStfi
InventorAndreas Uhmeier
Life of this patent
Estimating the term…
Abstract
A process and apparatus for manufacturing wood chips as raw material in the production of mechanical pulp in order to reduce energy consumption. The process includes irreversibly deforming a plurality of fibers of at least one piece of wood in a direction perpendicular to the longitudinal axis of the fibers. The wood fibers include summerwood fibers. The irreversible deformation is accomplished through mechanical treatment. The apparatus used includes one or several tools arranged so that the forces created during the process act in a direction substantially perpendicular to the longitudinal axis of the fibers so as to irreversibly deform the fibers across the grain.
Claims21
A process for producing wood chips for use as a raw material in the preparation of mechanical pulp, said method comprising the steps of:
- A) providing at least one cutting member including at least one cutting tool having a cutting edge for engaging at least one piece of wood;
- B) orienting said cutting edge parallel to a longitudinal axis of the fibres of said at least one piece of wood;
- and
- C) irreversibly deforming a plurality of said fibres of said at least one piece of wood in a direction perpendicular to the longitudinal axis of said fibres, said irreversibly deforming step including:
- 1) orienting said cutting tool relative to said at least one piece of wood such that a resulting chip angle of less than 60 degrees is formed during said process;
- 2) rotating said cutting member about an axis extending parallel to the longitudinal axis of said fibres;
- and
- 3) advancing said at least one cutting tool into said at least one piece of wood in a direction perpendicular to the longitudinal axis of said fibres so as to form the wood chips.
A process for producing wood chips as raw material for use in the production of mechanical pulp, said method including the steps of:
- A) providing a cutting tool having at least one cutting edge and means for receiving said at least one piece of wood;
- B) orienting said at least one cutting edge parallel to a longitudinal axis of the fibres of said at least one piece of wood;
- and
- c) irreversibly deforming a plurality of said fibres in a direction perpendicular to the longitudinal axis of said fibres, said irreversibly deforming step including:
- 1) rotating said cutting tool about an axis extending parallel to the longitudinal axis of said fibres;
- 2) advancing said cutting edge into said at least one piece of wood;
- and
- 3) creating strains in said at least one piece of wood that extend in a direction substantially perpendicular to said longitudinal axis of said fibres.
A process for producing wood chips for use as a raw material in the preparation of mechanical pulp, said method comprising irreversibly deforming a plurality of fibres of at least one piece of wood in a direction perpendicular to a longitudinal axis of said fibres.
An apparatus for irreversibly deforming wood fibres across the grain of a piece of wood, said apparatus comprising:
- means for receiving the piece of wood, a rotatable member having inner and outer surfaces and being capable of rotating relative to the piece of wood when operating, and a plurality of cutting tools positioned on one of said surfaces of said rotatable member for contacting the piece of wood, each said cutting tool including a cutting edge for positioning parallel to the length of the fibres of the piece of wood, said cutting edge of each cutting tool being oriented on said rotatable member so that a chip angle of between 0 and 30 degrees is formed and wood chips having thicknesses of between 0.2 mm and 2.0 mm are formed when said cutting tools are advanced into the piece of wood in a direction substantially perpendicular to the longitudinal axis of the wood fibres.
Dependencies are inferred from the claim text.