Patent ID: 7077931
Filing Date: 2006-07-18
Classification: D21C

Abstract:
1. A method of bleaching cellulose pulp in a bleaching line, comprising: providing the bleaching line having a first and a second bleaching step, as seen in a direction of flow of the cellulose pulp, the bleaching steps having a first wash apparatus and a second wash apparatus for the cellulose pulp arranged downstream of the first and the second bleaching step, respectively, directly connecting first, second, third and fourth branch conduits to a main conduit with the first branch conduit arranged first, as seen in a direction of a flow in the main conduit, and the second to fourth branch conduits in succession thereafter so that the first, second, third and fourth branch conduits are in direct fluid communication with one another via the main conduit, supplying a wash liquor in the main conduit that is arranged in parallel to the bleaching line, leading the wash liquor in the main conduit counter-currently to the flow of the cellulose pulp, diverting wash liquor, flowing in the main conduit, to the second wash apparatus of the second bleaching step, via the first branch conduit connected to the main conduit, leading a first portion of a wash filtrate from the second wash apparatus of the second bleaching step to the main conduit via the second branch conduit connected to the main conduit, diverting wash liquor, flowing in the main conduit, to the first wash apparatus of the first bleaching step via the third branch conduit connected to the main conduit, and leading a second portion of the wash filtrate from the first wash apparatus of the first bleaching step via the fourth branch conduit connected to the main conduit.