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
Application
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
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)
- [Y] CA 1186106 A 19850430 - BLACK CLAWSON CO, et al
- [Y] EP 0641883 A2 19950308 - BOC GROUP INC [US]
- [A] WO 8912716 A1 19891228 - FONGEN SIGURD [NO]
- [A] US 5352332 A 19941004 - MAPLES GERALD E [US], et al
- [A] WO 8806201 A1 19880825 - FONGEN SIGURD [NO]
Citation (third parties)
Third party :
- US 4834837 A 19890530 - LOQUENZ HEINZ [AT], et al
- US 4248662 A 19810203 - WALLICK SCOTT A
- US 4626319 A 19861202 - KRUEGER HORST [DE], et al
- US 4294654 A 19811013 - TURNER REX H
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