VERFAHREN UND VORRICHTUNG ZUR PAPIERHERSTELLUNG

• Main Authors: PAKKALA, ILKKA, SAVIA, RISTO, KOSKINEN, JORMA, LUND N, LEO, MARKKANEN, ESA
• Format: Patent
• Language: German
• Published: 30.12.2004
• Edition: 7
• Subjects: METHODS OF PRODUCING PAPER THEREON; PAPER-MAKING; PAPER-MAKING MACHINES; PRODUCTION OF CELLULOSE; TEXTILES

The invention relates to a method and an apparatus for pulp web formation. The method comprises feeding pulp, having a dry content of about 1,5 %, from a headbox (2) into a wedge-shaped converging space (5) defined by two wires (3, 4) or the like, said wires or the like being supported on chamber units (6, 7), including at a given time at least one water-receiving chamber (8), having its pressure adjustable in such a way that the pulp can be maintained at an overpressure in the space (5). The method comprises increasing the dry content of the pulp in the converging space (5) to a value which is at least about 10 % to about 12 %. According to the invention, the method comprises subjecting the pulp present between the wires (3, 4) or the like in the downstream section of the converging space, or in its substantially immediate vicinity, to a compression in perpendicular direction (z direction). In the method, the compression performed in the vicinity of the converging space (5) or its downstream section is used for increasing the dry content of the pulp to a value which is at least about 18 %, preferably to a value which is about 20 %.