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Abstract

The invention relates to a regulation method for an electrolytic cell for the production of aluminium by means of reduction of alumina dissolved in a molten cryolite bath and comprises the addition, in the electrolyte bath, during pre-determined time intervals p referred to as 'periods', of a determined quantity Q(p) of aluminium trifluoride (AlF.sub.3) determined by the following equation: Q(p)=Qint(p)-Qc1(p)+Qt(p), where Qint(p) is an integral (or 'self-adaptive') term which represents the total actual AlF.sub.3 requirements of the cell and which is calculated from a mean Qm(p) of the actual AlF.sub.3 supplies made during the last N periods, Qc1 is a compensating term corresponding to the so-called 'equivalent' quantity of AlF.sub.3 contained in the alumina added to the cell during the period p, and Qt(p) is a corrective term which is a typically increasing function of the difference between the measured bath temperature T(p) and the set-point temperature To. The method according to the invention makes it possible to regulate effectively the acidity of an electrolytic cell at intensities of up to 500 kA with an electrolyte bath having an AlF.sub.3 content greater than 11%.

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First Claim