Verfahren zur Flotation von Störstoffen aus einer wässrigen Faserstoffsuspension

摘要

The flotation system has a number of upright flotation vessels (4) to remove impurities from watery fiber suspensions (S) derived from used paper for recycling, and especially to separate and remove ink. The suspensions are fed into the vessels in a lateral flow, to rise in a stream of bubbles. The bubbles collect ink particles, to be removed as a foam from the suspension surface. The vessels have a rectangular cross section with a long side (5) length (L) at least 1.5 times longer than the width (B) of the short side, and preferably at least twice or three times the length.