Review of closed water loops with ore sorting and tailings valorisation for a more sustainable mining industry

Conservation and management of freshwater resources has become a major challenge of this century. In mining, one should be able to control the quantity of water intake, as well as the volume and quality of effluents. When the water loops in mining industry are closed, new methods for water quality control and optimisation at each process step are required, which facilitates also the recovery of additional valuable elements. The tightly closed water cycles necessitate that the tailings are filtered and stacked dry. Geopolymerisation of remaining tailings has the potential to be used for water and oxygen tight covers on the deposited tailings and for mine back-fill use. Detection of ore types and their classification or sorting by their geo-metallurgical properties before and in mill feed have a significant effect on metals recovery and on the process water quality in flotation. The main objective of this paper is to review the progress made towards a new paradigm shift at mine sites to recycle water and valorise tailings for an improved environmental and economic result, and for increased social acceptance of mine operations.