Global Patent Index - EP 0211945 A4

EP 0211945 A4 19870706 - METHOD AND APPARATUS FOR ALKALINE DELIGNIFICATION OF LIGNOCELLULOSIC FIBROUS MATERIALS.

Title (en)

METHOD AND APPARATUS FOR ALKALINE DELIGNIFICATION OF LIGNOCELLULOSIC FIBROUS MATERIALS.

Title (de)

VERFAHREN UND VORRICHTUNG ZUR ALKALISCHEN DELIGNIFIZIERUNG VON LIGNOZELLULOSE-FASERMATERIAL.

Title (fr)

PROCEDE ET APPAREIL DE DELIGNIFICATION ALCALINE DE MATERIAUX FIBREUX LIGNOCELLULOSIQUES.

Publication

EP 0211945 A4 19870706 (EN)

Application

EP 86901622 A 19860212

Priority

US 70157185 A 19850214

Abstract (en)

[origin: WO8604938A1] A process for the pretreatment of lignocellulosic fibrous materials prior to delignification. The process in one of its embodiments is comprised of the following steps: (1) contacting the pulp material with treated filtrate and alkali for a short reaction period of about 1 to 2 minutes at 40<o>C; (2) withdrawing part of the liquid phase by filtration; (3) displacing substantially all of the remaining liquid phase with treated filtrate, and (4) allowing the pulp to react under conditions normally used for alkaline extraction or oxygen delignification. The treated filtrate is obtained by subjecting the liquor removed from the pulp at steps 2 and 3 to temperatures of 50 to 60<o>C for periods of about 5 to 10 minutes. Alternatively, step 3 can be eliminated.

IPC 1-7

D21C 9/06; D21C 9/10; D21C 9/147; D21C 9/18

IPC 8 full level

D21C 9/10 (2006.01)

CPC (source: EP)

D21C 9/1026 (2013.01)

Citation (search report)

  • [X] US 3652388 A 19720328 - CROON INGEMAR LISS-ALBIN, et al
  • [X] US 4160693 A 19790710 - LINDAHL JONAS A I, et al
  • [A] US 4444621 A 19840424 - LINDAHL JONAS A I [SE]
  • [A] ABSTRACT BULLETIN OF THE INSTITUTE OF PAPER CHEMISTRY, vol. 51, no. 4, October 1980, page 474, abstract no. 4327, Appleton, Wisconsin, US; & JP-A-54 134 103 (SANYO KOKUSAKU PULP CO. LTD) 18-10-1979
  • See references of WO 8604938A1

Designated contracting state (EPC)

AT BE CH DE FR GB IT LI LU NL SE

DOCDB simple family (publication)

WO 8604938 A1 19860828; BR 8605554 A 19870422; CA 1275759 C 19901106; EP 0211945 A1 19870304; EP 0211945 A4 19870706; FI 864154 A0 19861014; FI 864154 A 19861014; JP S62501921 A 19870730

DOCDB simple family (application)

US 8600308 W 19860212; BR 8605554 A 19860212; CA 501953 A 19860214; EP 86901622 A 19860212; FI 864154 A 19861014; JP 50137086 A 19860212