Patent ID: 7294227
Filing Date: 2007-11-13
Classification: D21C

Abstract:
1. A method of treatment of pulp, comprising dewatering pulp to a fiber concentration of at least 20% dryness, shredding said dewatered pulp in a closed pulp-shredding vessel, transporting said shredded pulp from said pulp-shredding vessel through an outlet pipe to a gastight conduit of a reactor vessel by a transport screw which communicates with an interior of said outlet pipe and an interior of said reactor vessel, bleaching said shredded pulp in said reactor vessel through reaction with ozone gas, transporting said shredded pulp by said transport screw through said outlet pipe such that an upper gas space is formed in said outlet pipe between said pulp-shredding vessel and said gastight conduit, restraining a gas flow through said upper gas space between said pulp-shredding vessel and said gastight conduit, and maintaining a gas pressure in said pulp-shredding vessel lower than a gas pressure in said reactor vessel.