EP 0513140 B1 19950927 - A PROCESS FOR THE BLEACHING OF CHEMICAL PULP.
Title (en)
A PROCESS FOR THE BLEACHING OF CHEMICAL PULP.
Title (de)
VERFAHREN ZUM BLEICHEN VON CHEMISCHEM PAPIERZELLSTOFF.
Title (fr)
PROCEDE DE BLANCHIMENT DE PULPE CHIMIQUE.
Publication
Application
Priority
- FI 9100033 W 19910201
- FI 900549 A 19900202
Abstract (en)
[origin: WO9111553A1] The invention relates to a process for the bleaching of chemical pulp, process which comprises one or several oxidation steps and one or several alkali treatment steps and in which the pulp is treated with an enzyme. The essential idea of the invention is that the pulp is treated with an enzyme in two or more different steps of the process, an oxidation and/or alkali treatment being most preferably carried out between the enzyme treatment steps. The oxidizing chemical used is most preferably oxygen, although peroxide and/or chlorine and/or chlorine dioxide can also be used in addition to or instead of it, and in the enzyme treatment steps, which preferably number 2-4, the same enzyme or alternatively two or more different enzymes may be used. By the enzyme treatment according to the invention, the amount of toxic organic compounds inthe bleaching effluent is decreased and at the same time the chemical oxygen consumption of the effluent is decreased.
IPC 1-7
IPC 8 full level
D21C 5/00 (2006.01); D21C 9/10 (2006.01); D21C 9/14 (2006.01); D21C 9/147 (2006.01); D21C 9/16 (2006.01)
CPC (source: EP)
D21C 5/005 (2013.01); D21C 9/1057 (2013.01); D21C 9/142 (2013.01); D21C 9/147 (2013.01); D21C 9/163 (2013.01)
Designated contracting state (EPC)
AT BE CH DE DK ES FR GB GR IT LI LU NL SE
DOCDB simple family (publication)
WO 9111553 A1 19910808; AT E128498 T1 19951015; CA 2075187 A1 19910803; DE 69113444 D1 19951102; EP 0513140 A1 19921119; EP 0513140 B1 19950927; EP 0513140 B2 19980318; ES 2079062 T3 19960101; ES 2079062 T5 19980716; FI 89814 B 19930813; FI 89814 C 19931125; FI 900549 A0 19900202; FI 900549 A 19910803; JP H05509362 A 19931222
DOCDB simple family (application)
FI 9100033 W 19910201; AT 91903684 T 19910201; CA 2075187 A 19910201; DE 69113444 T 19910201; EP 91903684 A 19910201; ES 91903684 T 19910201; FI 900549 A 19900202; JP 50375291 A 19910201