Estimating the Capital Costs of Electrowinning Processes
Caspar Stinn, Antoine Allanore
Abstract
Novel electrolysis processes remain strong technological contenders for advances in sustainable materials processing, in particular metals, yet will need to compete economically with currently-deployed production facilities. To evaluate the technoeconomic efficacy of new electrolytic metal extraction processes, an understanding of the capital and operating costs of electrowinning is necessary. Estimation of electrochemical operating costs has been afforded due attention, yet capital cost (CAPEX) trends are far less understood. Herein, we attempt to show that estimating the capital costs of electrowinning processes via conventional chemical engineering scaling laws is not possible. Instead, we propose a capital cost model for electrochemical processes based on relevant operating parameters such as current density, temperature, and voltage. The new model for capital cost describes within ±30 to 100% the capex for existing electrochemical processes, sufficient for order of magnitude and preliminary design capital cost estimation.