Mass balance and techno-economic study of a complete treatment chain of bio-oxidation for the extraction and recovery of precious metals from gold ore

Abstract

A techno-economic feasibility study of a complete chain of bio-oxidation treatment for the extraction of gold ore with refractory character was carried out. Several basic parameters were considered, including operating and technical parameters, capitalization parameters, direct and indirect costs of the operation, and basic market parameters. The data generated were used to develop a preliminary techno-economic model. SuperPro Designer software was used to identify the industrialization potential of the project. With an estimated total capital investment (TCI) of 220 M$ and an estimated operating cost of 58.27 M$/a, we estimate that a total revenue of 78.48 M$/a is achievable. Other economic data were also estimated such as a gross margin of 25.75 %, a return on investment (ROI) of 15.82 %, a payback period of 6.32 years, and an internal rate of return (IRR) of 9.55 %. All this project was shown to have a net present value (NPV) of 34.40 M$ and an interest rate of 7 % per year, which is considered a profit. The process was shown to be most sensitive to the change in gold price.