Conversion of used paper into papermaking pulp, for quality graphic papers, has a fine sorting for the suspension while the rejected matter is separated into long and short fiber fractions for further cleaning and processing

摘要

To process used paper materials, for recycling, the used paper (M) together with any stickies is formed into a suspension (S) with water (W). The suspension is given an initial cleaning (2) to be followed by a fine sorting stage (3). During fine sorting, the rejects (R3) are taken off continuously to give a clean usable material (A3). The rejected matter is passed through a fiber fraction unit (4) to be divided into a long fiber fraction (LF4), and a short fiber fraction (KF4) which can still contain some clinging impurities to be detached in a separation stage (6). The long fiber fraction is passed directly to a beating stage (5).