Global Patent Index - EP 0874935 B1

EP 0874935 B1 20000510 - PROCESS FOR PRODUCING PULP FROM LIGNOCELLULOSIC PLANTS, AND PULP OBTAINED

Title (en)

PROCESS FOR PRODUCING PULP FROM LIGNOCELLULOSIC PLANTS, AND PULP OBTAINED

Title (de)

VERFAHREN ZUR HERSTELLUNG VON PAPIERZELLSTOFF AUS LIGNOCELLULOSISCHEN PFLANZEN SOWIE DANACH HERGESTELLTER PAPIERZELLSTOFF

Title (fr)

PROCEDE DE FABRICATION DE PATE A PAPIER A PARTIR DE PLANTES LIGNOCELLULOSIQUES ET PATE A PAPIER OBTENUE

Publication

EP 0874935 B1 20000510 (FR)

Application

EP 97900645 A 19970115

Priority

  • FR 9700065 W 19970115
  • FR 9600760 A 19960117

Abstract (en)

[origin: WO9726401A1] The invention relates to a process for producing pulp, from raw lignocellulosic material based on annual or perennial plants, or residues of such plants. The process comprises impregnating said raw material with an aqueous soda solution such that the weight proportion of soda is substantially comprises between 3.5 % and 10 % based on the dry material and that the weight ratio of hydration of the cellulosic material after impregnation is at least equal to 40 %, and subjecting the lignocellulosic material thus impregnated to vapocracking which consists in pressurising said material under saturated vapour conditions and producing a sudden expansion through a direct passage valve. The solid fraction which forms the pulp is then separated from the aqueous phase and the hydrosoluble products. The process yields good quality pulps characterized particularly by a braking length higher than 5500 meters, and having a high lignine ratio (KAPPA index comprises between 60 and 65).

IPC 1-7

D21B 1/36; D21B 1/02; D21C 5/00; D21C 1/06

IPC 8 full level

D21B 1/00 (2006.01); D21B 1/36 (2006.01); D21C 1/06 (2006.01); D21C 5/00 (2006.01)

CPC (source: EP)

D21B 1/00 (2013.01); D21B 1/36 (2013.01); D21C 1/06 (2013.01); D21C 5/00 (2013.01)

Designated contracting state (EPC)

AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

DOCDB simple family (publication)

WO 9726401 A1 19970724; AT E192798 T1 20000515; CA 2242232 A1 19970724; CN 1077630 C 20020109; CN 1214091 A 19990414; DE 69701960 D1 20000615; DE 69701960 T2 20010125; EP 0874935 A1 19981104; EP 0874935 B1 20000510; ES 2146456 T3 20000801; FR 2743579 A1 19970718; FR 2743579 B1 19980306

DOCDB simple family (application)

FR 9700065 W 19970115; AT 97900645 T 19970115; CA 2242232 A 19970115; CN 97193114 A 19970115; DE 69701960 T 19970115; EP 97900645 A 19970115; ES 97900645 T 19970115; FR 9600760 A 19960117