Patent ID: 6053439
Filing Date: 2000-04-25
Classification: D21B,D21D,Y02W

Abstract:
The method of treating waxed fiber paper product having a high wax content substantially in excess of 1% by weight providing a paper board finish which has an acceptably small wax content, such as about 1% by weight or less, comprising the steps of pulping such waxed paper fiber product with added water at an elevated temperature in excess of the melting point of the wax forming a heated pulp suspension comprising a pulp fraction in an emulsion of water and molten wax, diluting said pulp suspension with heated dilution water to a low consistency of about 1% or less, apparatus having therein a screen and defining a high pressure screen inlet side and a low pressure screen outlet side and having perforations therein of a sufficiently small size as to prevent a major portion of the fibers in poised suspension from passing therethrough and extending from said high pressure inlet side to said low pressure outlet side and further having moving pressure impulse foils in close proximity to said high pressure inlet side, applying said low consistency suspension under pressure to said screen high pressure inlet side and simultaneously causing said foils to move along said screen inlet side at a rate sufficient to maintain fibers in said suspension in a fluidized state and prevent blocking of said screen perforations by said fibers, and extracting a major portion of such water and wax emulsion from said suspension through said screen perforations.