FLOTATION-DEINKING METHOD WITH IMPROVING YIELD FOR WASTE PAPER

摘要

A flotation de-inking method of waste paper with an improved yield is provided to perform the enzyme treatment of the first flotation reject powder. A hydrophobic material is concentrated after the floating process. The concentrated flotation reject is separated and discharged. One or more enzymes selected from a group consisting of esterase, lipase or cutinase are injected into the entire waste paper in a Froth-Flotation Cell and the only adsorbed material is selectively modified into hydrophilic material. The addition amount of the enzyme is 0.02-2 weight % relating to the dry weight of the entire waste paper. The hydrophobic material is the functional additive or cohesive foreign substance.