Process for making pulp from papercontaining material

摘要

In a waste paper recovery process dry chopped waste paper particles are esp. subject to dry fractionation prior to the admixture of process water. The dry fractionation separates particles into light (HF) and dark coloured (DF). The light fraction has a maximum of 3% soft and 0.5% hard foreign bodies. In a paper-making process waste paper (M) is chopped (1) to a maximum particle size of 200 mm from which foreign bodies are removed and the particles dry-graded. Water is admixed to particles, bringing dry matter content to between 4% and 35%. The solids are broken down (4) by specific energy of 5 kWh/ton and the dry matter content is reduced to below 6%. The solid matter is broken down by a cellulose separator working with a mixture of between 15% and 35% dry matter. The separator is a single-shaft unit (14) with 10 mm kneading blade separation moving at a relative speed of no more than 15 m/sec.