A new algorithm to determine optimum cut-off grades considering technical, economical, environmental and social aspects

Optimum cut-off grades with different types of objective functions are determined by optimization algorithms which recognized as the one of the basis of sustainable development indicators of mining. As different mineral processing methods are applied in mines, it is very essential to choose the most appropriate cut-off grades determination algorithm. The current paper is going to analyze the bioheap leaching method and their associated environmental considerations on optimum cut-off grades policy. Remarking the importance of capital costs, these costs are evaluated in the model. Since the recovery of processing methods are changed based upon copper content, the recovery is considered variable in determining optimum cut-off grades. Presented model is evaluated in Sungun Copper Mine where the hydrometallurgical tests confirm the possibility of using bioheap leaching method to extract copper from its sulfide ores. It is observed that using bio-heap leaching method for low grade copper ores is subjected not only to improve the NPV of copper mines but also to decrease the adverse environmental impacts and produce sustainable results from mining activities.