METHOD FOR DEINKING OF WASTE PAPER

摘要

PROBLEM TO BE SOLVED: To provide a method for deinking old paper, capable of forming reclaimed pulp having fixed whiteness and completely eliminating or extremely reducing the use of a bleaching agent. SOLUTION: Old paper is deinked by a process for macerating the old paper in an alkali aqueous solution containing sodium sulfite and sodium carbonate and forming a fiber slurry having pH at least about 7.5, a process for separating ink from the paper fiber and a process for removing the separated ink from the slurry.