Assessment of technologies and water circularity in mining processes: An innovative methodological approach

The rapid expansion of mining operations has accelerated water resource depletion and increased energy consumption. To tackle these issues, the circular economy provides a framework for managing resource use and reducing environmental impacts. This study introduces an innovative method for assessing circularity in mineral processing, supported by a case study that demonstrates the methodology. The approach is based on circularity indices and employs Monte Carlo simulations to account for epistemic uncertainties that are typical in this field. If the results are not sufficiently robust, global sensitivity analysis is utilized to pinpoint critical variables that require refinement to enhance the outcomes. Additionally, multicriteria decision analysis methods are applied to further the study. In a case study focused on copper concentration through flotation, optimizing water recovery methods significantly improved water circularity metrics. Furthermore, dewatering technologies increased the system's circularity by 28%, with similar improvements across different setups, reducing water extraction by approximately 42% and lowering water loss from 0.56 in the base case to 0.29, a 48.6% decrease. This highlights the effectiveness of dewatering technologies in circular resource management. Then, by applying multicriteria decision-making methods and giving more weight to general indicators related to the water–energy nexus, paste tailings thickening technology was identified as the best option for improving circularity and advancing sustainability. This methodology provides a solid foundation for assessing the transition from a recirculation-based economy to a truly circular model, offering global applicability for comparing technologies, companies, and other relevant factors in mineral processing. • A method to assess water circularity in mineral processing using indicators is outlined • The indicators are categorized based on both circularity and sustainability goals • The method was validated by applying uncertainty and global sensitivity analyses • The method is useful for shifting from a recirculation-based economy to a circular model • A case study effectively showcases the numerous benefits of the methodology