The effect of electrode shape on the voltage of hall/heroult cells—I. carbon anodes/wetted cathodes

✍ Scribed by Geoffrey A. Prentice; Paul J. Sides

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 558 KB
• Volume: 33
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(88)80083-5

✦ Synopsis

Two-dimensional profiles assumed by carbon anodes suspended over shaped, wetted cathodes in the Hall process for aluminum production and the cell voltage of each configuration were calculated. Cathodes shaped as square waves, sine waves and triangular waves were used. Designation of a region of lower conductivity adjacent to the anode simulated the presence ofcarbon dioxide bubbles. The profile of the anode did not penetrate the shape of the cathode. A dimensionless group characterizing the response of the anode profile to a wave sculpted into the cathode is SE -npFiavgb,, rl F ZsrcRT(b, + h,)

where s is the stoichiometric coefficient, p is the reaction order, A is the number of electrons transferred, b, is the amplitude of the cathode wave, ho is the minimum separation of anode from the cathode, and i, is the wavelength of the cathode wave. Cell voltages in all cases were greater than the voltage of a cell having the same amount of gas spread uniformly over a lIat plane. Voltage reduction can be achieved if the shape cut into the anode aids removal of gas from the interelectrode region.