Global Patent Index - EP 1528149 A1

EP 1528149 A1 20050504 - Low consistency oxygen delignification process

Title (en)

Low consistency oxygen delignification process

Title (de)

Verfahren zur Niederkonsistenz-Sauerstoffdelignifizierung

Title (fr)

Procédé pour la délignification à l'oxygène à faible consistance

Publication

EP 1528149 A1 20050504 (EN)

Application

EP 04256503 A 20041022

Priority

  • US 51494603 P 20031028
  • US 89810104 A 20040723

Abstract (en)

A method for delignifying softwood or hardwood pulp taken from a fiber line of a pulp and papermaking system comprises adding oxygen to the pulp slurry and mixing the slurry under conditions of temperature and pressure whereby the oxygen reacts with lignin present in the pulp. The delignification is performed on pulp having a low consistency, i.e. containing less than 8% by weight of cellulosic material. The pulp for delignification is preferably taken from a point upstream of knotters in the papermaking system but downstream of brown stock washers so as to make effective use the residual alkali and heat content in the incoming black liquor.

IPC 1-7

D21C 9/147

IPC 8 full level

D21C 9/147 (2006.01); E21B 29/08 (2006.01); E21B 34/10 (2006.01)

CPC (source: EP US)

D21C 9/147 (2013.01 - EP US)

Citation (search report)

Citation (third parties)

Third party :

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR

DOCDB simple family (publication)

EP 1528149 A1 20050504; AU 2004222766 A1 20050512; CA 2484557 A1 20050428; US 2005087315 A1 20050428

DOCDB simple family (application)

EP 04256503 A 20041022; AU 2004222766 A 20041020; CA 2484557 A 20041013; US 89810104 A 20040723