Metod för tillverkning av mekanisk eller kemi-mekanisk massa och en anordning för tillverkning av densamma

摘要

The present invention relates to a method for manufacturing mechanical or chemi-mechanical pulp by disintegrating and treating wood material. The wood material is defibrated in a first step with a low energy input compared to conventional processes. Then the reject is screened from the defibrated wood material. The reject is then refined separately and mixed again with the rest defibrated material to a final pulp product. The invention also relates to an apparatus for manufacturing mechanical or chemi-mechanical pulp by disintegrating and treating wood based material. The apparatus comprises a defibration device (1) with a low energy input, a screening device (2) separating reject from the main part of the defibrated wood material, a reject refining device (4) and a device for (6) mixing the refined reject with the rest of the wood based material.One object of the invention is to carry out the disintegration and the refining of the pulp in such a manner, that the total energy consumption is substantially reduced relative to common practice.It is a further object of the invention to provide a method and apparatus by which it is easy to control through choice of energy inputs the characteristics of the end product by controlling the properties of the defibrated wood material through the process.