Global Patent Index - EP 0492364 B1

EP 0492364 B1 19950712 - Control system to monitor the production of pulp in a discontinuous digester.

Title (en)

Control system to monitor the production of pulp in a discontinuous digester.

Title (de)

Prozessleitsystem zur Steuerung der Herstellung von Zellstoff in einem diskontinuierlich arbeitenden Kocher.

Title (fr)

Système de commande pour diriger la production de pâte à papier dans un digesteur en discontinu.

Publication

EP 0492364 B1 19950712 (DE)

Application

EP 91121599 A 19911217

Priority

DE 4041456 A 19901221

Abstract (en)

[origin: EP0492364A1] The object of the invention is to control the digestion in such a way that a desired pulp quality is available, as far as possible, simultaneously with the reaching of a preset digestion end point. A process control system is used for this purpose. This comprises first means which, for homogenising the starting conditions, follow up, in accordance with a set value, the quotient of the mass of at least one constituent of the digesting fluid, relative to the dry mass of wood in the digester, especially by replenishing with or stripping out at least one digesting fluid component, or by controlled draining of digesting fluid. Second means subject the digester to a pressure pulse, whereas third means avoid major temperature differences in the digester by acting on the circulation stream of the digesting fluid. Further, fourth means effect a presetting of the digesting temperature with the aid of a simulated pulp quality figure. Finally, fifth means can be provided which, at an unchanged digesting temperature, effect a fine adjustment of the digestion end point required to reach the pulp quality. For this purpose, the actual state of the digesting fluid is measured, especially by an extinction measurement, and/or the actual value of a pulp quality figure is measured. <IMAGE>

IPC 1-7

D21C 7/12; D21C 3/22

IPC 8 full level

D21C 3/22 (2006.01); D21C 7/12 (2006.01)

CPC (source: EP)

D21C 3/228 (2013.01); D21C 7/12 (2013.01)

Designated contracting state (EPC)

AT CH DE FR GB LI SE

DOCDB simple family (publication)

EP 0492364 A1 19920701; EP 0492364 B1 19950712; AT E125011 T1 19950715; DE 59105982 D1 19950817; DE 9017325 U1 19920102

DOCDB simple family (application)

EP 91121599 A 19911217; AT 91121599 T 19911217; DE 59105982 T 19911217; DE 9017325 U 19901221