Method of deinking recycled paper employing centrifigal cleaners

Abstract

A method of deinking recycled cellulosic paper including the steps of developing a pulp containing paper fibers and bundles of paper fibers in a pulping liquid and an agglomerating agent, subjecting the pulp to a screening treatment, storing the filtrate from the screening treatment, and which includes residual pulping chemicals, in a vessel for a time sufficient to effect a change in the geometry or other characteristic (other than size) of individual ones of the ink particles in the filtrate, and thereafter subjecting the pulp withdrawn from the vessel to a cyclone cleaner treatment to deplete the pulp of modified ink particles and develop a pulp containing paper fibers and substantially fewer ink particles relative to the quantity of ink particles present in the screen filtrate, and collecting the pulp of depleted ink particle content for use in a papermaking operation.

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