INK REMOVAL FROM WASTE INKED PAPER

摘要

1482458 Deinking paper NATIONAL RESEARCH COUNCIL OF CANADA and ONTARIO PAPER CO Ltd 25 Oct 1974 [25 Oct 1973] 46272/74 Headings B2H and B2P [Also in Division D2] A method of deinking waste inked paper comprises (a) freeing the ink particles adhering to the paper fibres; (b) agitating the resulting mixture with solid particles at least 0.03 mm in diameter and, having hydrophobic surfaces with a strong affinity for the ink particles; (c) separating the resulting inkcoated particles from the paper fibres otherwise than by froth flotation and (d) recovering the cleaned paper stock. The ink particles may be freed from the paper fibres by treating an aqueous pulp of the waste paper with an appropriate surfactant e.g. a soap and a caustic alkali. The alkali may be added as peroxide. Sodium silicate with or without soap or alkali may also be used. The waste paper may be wax, polyolefin or other vinyl polymer, rubber, pitch, gum, sulphur or modified silica particles. The surface of the particles may be coated with a hydrophobic adhesive substance e.g. sticky oils, waxes, gums, or the solids may be plasticised to increase adhesion. A magnetic component may be incorporated in the particles to permit magnetic separation of the ink-loaded particles from the paper fibres. The particles may be separated by other means e.g. by filtration, screening, centrifuging or settling. The ink may be removed from the particles, and the latter reused.