Global Patent Index - EP 0834601 B1

EP 0834601 B1 20000426 - Process for controlling the bath temperature in an aluminium electrolysis cell

Title (en)

Process for controlling the bath temperature in an aluminium electrolysis cell

Title (de)

Verfahren zur Temperaturregelung eines Bades in einer Aluminium-Elektrolysewanne

Title (fr)

Procédé de régulation de la température du bain d'une cuve d'électrolyse pour la production d'aluminium

Publication

EP 0834601 B1 20000426 (FR)

Application

EP 97420174 A 19970924

Priority

FR 9611962 A 19960925

Abstract (en)

[origin: EP0834601A1] Thermal regulation of individual electrolysis cells for the production of aluminium comprises directly measuring the temperature of the bath at regular time intervals and modifying the distance between the anode and the metal as a function of the measured values of the resistance R of the cell w.r.t. a consigned resistance (Ro). During each cycle of thermal regulation of duration (Tr) corresponding to a working sequence incorporated in the duration (T) of the work cycle of the cell the following steps are taken: (a) at least one measurement of the bath temperature (θ ) is effected; (b) from the n latest measures a corrected average temperature (θ mc) representative of the medium state of the cell assembly and free from the variations in the time and space due to the periodic operations of exploitation is determined; (c) an additional resistance (RTH) is determined, this may be positive or negative and comprises two terms: (i) a prior correction term (RTHa), calculated in a manner to neutralise by anticipation the irregular but known and quantified perturbations such as the addition of solids to the bath; and (ii) a posterior correction term (RTHb), calculated as a function of the corrected average temperature (θ mc) and a consigned temperature (θ o); and (d) the additional resistance (RTH) is then applied to the consigned resistance (Ro) of the cell in order to maintain or correct the temperature of the cell.

IPC 1-7

C25C 3/20

IPC 8 full level

C25C 3/20 (2006.01)

CPC (source: EP US)

C25C 3/20 (2013.01 - EP US)

Designated contracting state (EPC)

ES FR GB

DOCDB simple family (publication)

FR 2753727 A1 19980327; FR 2753727 B1 19981023; AU 3920097 A 19980402; AU 717983 B2 20000406; BR 9704860 A 19981229; BR 9704860 B1 20090113; CA 2215186 A1 19980325; CA 2215186 C 20030128; EG 20880 A 20000531; EP 0834601 A1 19980408; EP 0834601 B1 20000426; ES 2146967 T3 20000816; IN 192036 B 20040214; NO 317403 B1 20041025; NO 974304 D0 19970918; NO 974304 L 19980326; NZ 328743 A 19990128; US 5882499 A 19990316; ZA 978544 B 19980511

DOCDB simple family (application)

FR 9611962 A 19960925; AU 3920097 A 19970924; BR 9704860 A 19970924; CA 2215186 A 19970922; EG 97097 A 19970920; EP 97420174 A 19970924; ES 97420174 T 19970924; IN 1691CA1997 A 19970915; NO 974304 A 19970918; NZ 32874397 A 19970915; US 93305797 A 19970918; ZA 978544 A 19970923