EP 1155183 A1 20011121 - OXYGEN GAS BLEACHING OF PULP
Title (en)
OXYGEN GAS BLEACHING OF PULP
Title (de)
BLEICHEN VON ZELLSTOFF MITTELS SAUERSTOFF
Title (fr)
BLANCHIMENT DE PATE A L'OXYGENE
Publication
Application
Priority
- SE 9901761 W 19991004
- SE 9803474 A 19981008
Abstract (en)
[origin: WO0020678A1] The present invention relates to a method of oxygen gas delignifying lignocelllulosic pulp material in two stages, where a regulation occurs in that in the first reactor, the pressure in the top of the reactor as well as the level of pulp in the reactor are kept constant with the aid of two regulating valves (1 and 2). The first regulating valve (1) is placed in the top of the reactor and the second regulating valve (2) is placed immediately beneath the level of pulp. The first regulating valve (1) is controlled partly by the gas pressure and partly by the pressure difference measured between a first pressure sensor (3) located in the top of the reactor and a second pressure sensor (4) located in the upper part of the reactor and below the level of pulp. The second regulating valve (2) is controlled by the pressure in the top of the reactor such as to maintain the pressure at a desired level. The major part of the gas is discharged through the first regulating valve (1).
IPC 1-7
IPC 8 full level
D21C 9/10 (2006.01); D21C 9/147 (2006.01)
CPC (source: EP)
D21C 9/1052 (2013.01); D21C 9/147 (2013.01)
Citation (search report)
See references of WO 0020678A1
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
DOCDB simple family (publication)
WO 0020678 A1 20000413; BR 9914337 A 20010626; EP 1155183 A1 20011121; JP 2002526684 A 20020820; SE 9803474 D0 19981008; SE 9803474 L 20000409
DOCDB simple family (application)
SE 9901761 W 19991004; BR 9914337 A 19991004; EP 99956419 A 19991004; JP 2000574767 A 19991004; SE 9803474 A 19981008