METHOD AND DEVICE FOR DECOLORING SUSPENDED AND SEPARATED COLUMN OF PAPER

摘要

PURPOSE: To efficiently deink recovered paper pulp by treating a fibrous suspension from a flotation column under specified conditions. CONSTITUTION: The opened bottom end 32 of a first column 30 is disposed in a second column 33 to erect substantially vertically both columns. A fibrous suspension of about 2-8% concentration of finely pulverized solids is introduced to the top 31 of the first column to flow downwardly. Air from an air source 41 is accompanied by the suspension stream to form a foam bed moving downwardly and the interface 46 of the suspension/froth layers is formed in the second column. Ink particles are adhered to the air bubbles and moved to the froth layer side 47. The froth layer is withdrawn from the top 35 of the second column and the suspension is withdrawn from the bottom 36.