EP 0840820 B1 19990428 - METHOD AND APPARATUS FOR BLEACHING PULP WITH A GASEOUS BLEACHING REAGENT
Title (en)
METHOD AND APPARATUS FOR BLEACHING PULP WITH A GASEOUS BLEACHING REAGENT
Title (de)
VERFAHREN UND VORRICHTUNG ZUM ZELLSTOFFBLEICHEN MIT EINEM GASFÖRMIGEN BLEICHMITTEL
Title (fr)
PROCEDE ET EQUIPEMENT DE BLANCHIMENT DE PATE A PAPIER AU MOYEN D'UN REACTIF DE BLANCHIMENT GAZEUX
Publication
Application
Priority
- US 9612902 W 19960716
- US 144795 P 19950726
Abstract (en)
[origin: WO9705327A1] A method and apparatus for bleaching pulp with a gaseous bleaching reagent. The pulp (18) is intensively mixed in the presence of the bleaching reagent within an upstream vessel comprising a fluffer/blower (12). Next, the pulp is agitated in the presence of the bleaching reagent within an intermediate vessel comprising an agitated mixer reactor (14). The pulp is then discharged to a downstream vessel, comprising a porous bed reactor (16), where it is further reacted with the bleaching reagent. The concentration of the gaseous bleaching reagent supplied to each vessel is separately controlled which, in combination with a controlled pulp residence time within at least the agitated mixer reactor and the porous bed reactor, results in an economy of energy utilization, a minimization of pulp particle damage due to mechanical mixing, and uniformity of pulp bleaching.
IPC 1-7
IPC 8 full level
D21C 9/10 (2006.01); D21C 9/153 (2006.01)
CPC (source: EP)
D21C 9/10 (2013.01); D21C 9/153 (2013.01)
Designated contracting state (EPC)
AT DE ES FI SE
DOCDB simple family (publication)
WO 9705327 A1 19970213; AT E179469 T1 19990515; BR 9609840 A 19990309; CA 2227690 A1 19970213; DE 69602269 D1 19990602; DE 69602269 T2 19990916; EP 0840820 A1 19980513; EP 0840820 B1 19990428; JP H10510599 A 19981013
DOCDB simple family (application)
US 9612902 W 19960716; AT 96928093 T 19960716; BR 9609840 A 19960716; CA 2227690 A 19960716; DE 69602269 T 19960716; EP 96928093 A 19960716; JP 50791897 A 19960716