Global Patent Index - EP 1061173 A1

EP 1061173 A1 20001220 - Oxygen delignification of lignocellulosic material

Title (en)

Oxygen delignification of lignocellulosic material

Title (de)

Delignifizierung von lignocellulosischem Material mittels Sauerstoff

Title (fr)

Délignification de matériaux lignocellulosiques avec de l'oxygène

Publication

EP 1061173 A1 20001220 (EN)

Application

EP 00111891 A 20000613

Priority

US 33098399 A 19990614

Abstract (en)

The invention configures a process for delignifying pulp wherein one stage of a two stage oxygen delignification plant is obviated. In particular, a pulp soak stage enables a pulp stream to be mixed with an alkali feed and held in residence for a sufficient period of time to allow an alkali hydrolysis leaching of colored materials from the pulp and a swelling of the pulp fibers. Next, the pulp stream is combined with an oxygen feed and is processed through a mixer. The output of the mixer is fed to a pressurized reactor where oxygen reacts with lignin of the pulp fibers. The swelled pulp fibers facilitate the oxygen reaction with lignin and removal of additional colored materials. <IMAGE>

IPC 1-7

D21C 9/10; D21C 9/147

IPC 8 full level

D21C 9/10 (2006.01); D21C 9/147 (2006.01)

CPC (source: EP KR)

D21C 9/1005 (2013.01 - EP); D21C 9/147 (2013.01 - EP KR)

Citation (search report)

  • [X] US 4806203 A 19890221 - ELTON EDWARD F [US]
  • [X] US 5085734 A 19920204 - GRIGGS BRUCE F [US]
  • [A] WO 9727358 A2 19970731 - BELOIT TECHNOLOGIES INC [US]
  • [X] VILPPONEN A ET AL: "DELIGNIFICATION BY HOT ALKALI EXTRACTION", TAPPI JOURNAL,US,TECHNICAL ASSOCIATION OF THE PULP & PAPER INDUSTRY. ATLANTA, vol. 76, no. 2, 1 February 1993 (1993-02-01), pages 134 - 138, XP000345097, ISSN: 0734-1415

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)

EP 1061173 A1 20001220; BR 0002634 A 20010102; CA 2311718 A1 20001214; CN 1277283 A 20001220; JP 2001003287 A 20010109; KR 100538083 B1 20051222; KR 20010049536 A 20010615; NO 20003014 D0 20000613; NO 20003014 L 20001215

DOCDB simple family (application)

EP 00111891 A 20000613; BR 0002634 A 20000613; CA 2311718 A 20000613; CN 00121746 A 20000613; JP 2000176554 A 20000613; KR 20000032341 A 20000613; NO 20003014 A 20000613