Modelling the effect of solution composition and temperature on the conductivity of zinc electrowinning electrolytes

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A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
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Metals, Volume 11, issue 11
Zinc electrowinning is an energy-intensive step of hydrometallurgical zinc production in which ohmic drop contributes the second highest overpotential in the process. As the ohmic drop is a result of electrolyte conductivity, three conductivity models (Aalto-I, Aalto-II and Aalto-III) were formulated in this study based on the synthetic industrial electrolyte conditions of Zn (50–70 g/dm3), H2SO4 (150–200 g/dm3), Mn (0–8 g/dm3), Mg (0–4 g/dm3), and temperature, T (30–40◦C). These studies indicate that electrolyte conductivity increases with temperature and H2SO4 concentration, whereas metal ions have negative effects on conductivity. In addition, the interaction effects of temperature and the concentrations of metal ions on solution conductivity were tested by comparing the performance of the linear model (Aalto-I) and interrelated models (Aalto-II and Aalto-III) to determine their significance in the electrowinning process. Statistical analysis shows that Aalto-I has the highest accuracy of all the models developed and investigated in this study. From the industrial validation, Aalto-I also demonstrates a high level of correlation in comparison to the other models presented in this study. Further comparison of model Aalto-I with the existing published models from previous studies shows that model Aalto-I substantially improves the accuracy of the zinc conductivity empirical model.
Funding Information: Acknowledgments: Grateful thanks to Boliden Odda Zinc Smelter for allowing field measurements to be undertaken at their plant. The RawMatTERS Finland Infrastructure (RAMI) funded by Academy of Finland and based at Aalto University is also acknowledged. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Conductivity model, Energy consumption, Industrial validation, Zinc electrowinning
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Wang , Z , Aji , A T , Wilson , B P , Jørstad , S , Møll , M & Lundström , M 2021 , ' Modelling the effect of solution composition and temperature on the conductivity of zinc electrowinning electrolytes ' , Metals , vol. 11 , no. 11 , 1824 .