Copper Electrowinning using Segmented Intercell Bars for Improved Current Distribution

Abstract The most widely used technology for obtaining pure copper (>99.999% Cu) from copper oxide ores is LIX-SX-EW (Leaching – Solvent Extraction – Electrowinning). In the EW step, the maximum current that can be applied is partially limited by the possibility of the formation of short circuits. The Walker configuration, despite its apparent robustness and simplicity, exhibits high dispersion of the electrode currents. This paper reviews the current distribution phenomena and proposes a Whitehead based configuration implemented with a multicircuit intercell bar to force the current balance. This arrangement drives the current through more balanced resistance circuits despite intrinsic process parameter deviations. A more even current distribution produces cathodes capable of complying with tighter standards improving chemical and physical cathode quality parameters. Also, the proposed configuration can decrease the probability of short circuit formation allowing operation at higher current densities. Finally, use of the proposed electrical arrangement makes possible the continuous measurement of the flow of current in each electrode using current sensors. This allows for the early detection/correction of short circuits and continuous monitoring of the current distribution in the whole cellhouse.