Membrane technology for a sustainable copper mining industry: The Chilean paradigm

Mining is an economically-beneficial activity recognized as crucial in modern society since almost every aspect of our lives relies on minerals. However, intensive mining activities impose a severe strain on the water-energy nexus. In fact, mining ventures: i) need massive amount of water in various ore processing steps; ii) generate a huge amount of waste (tailings), generally transferred to tailing ponds or dams, that are a potential source of contamination and adverse ecological effects; iii) are energy-intensive practices in the extraction and transformation phases. These aspects confirm the urgent need of a paradigm shift towards a sustainable mining industry. Herein, we provide a comprehensive and critical survey on the opportunities offered by the integration of conventional and emerging membrane technologies for a sustainable development of copper mining industry, coherently with the Circular Economy paradigm. This work critically discusses the potential and challenges of conventional and innovative membrane processes for water management of the mining industry value chain, with specific focus on the remediation of waste aqueous streams and reuse of clean water. Beside the alleviation of the pressure on water bodies, attention is paid to the valorization by the recovery of valuable minerals and blue energy generation via advanced technologies such as highly selective membrane separation, membrane distillation/crystallization and reverse electrodialysis. Economic implications elucidated about the benefits from the recovered water and raw materials from mining waste. Due to its prominence and strategic relevance in global copper market, Chilean copper mining industry is here considered as case study.