Process for the breaking and cleaning of contaminant-containing raw paper stocks, in particular of recovered paper

US6651679B2 · kind B2 · utility

Assignee

• Voith Paper Patent GmbH · DE

Inventors

• Michael Danger · Salem, DE
• Peter Respondek · Meinerzhagen, DE
• Reimund Rienecker · Heidenheim, DE
• Samuel Schabel · Ravensburg, DE

Key dates

• Filing date: Dec 14, 2001
• Grant date: Nov 25, 2003
• Expiry date: Feb 8, 2022

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02W30/64
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

Process for the disintegration and cleaning of contaminant-containing raw paper stocks. The process includes producing a contaminant-containing suspension, feeding the contaminant-containing suspension to a closed coarse screen, drawing of a cleaned flow fraction from the closed coarse screen, and drawing off an overflow fraction containing an increased amount of contaminants from the coarse screen during at least about 80% of an operating time. The process also includes adjusting a volumetric mass flow of the overflow fraction to at least about 15% and maximally about 50% of a volumetric mass flow of an inflow into the coarse screen, and feeding the overflow fraction to a screening device, in which contaminants collected are sluiced out discontinuously as a further overflow fraction, thereby forming a further cleaned flow fraction.