Pre-mining Characterization of Ore Deposits: What Information Do We Need to Increase Sustainability of the Mining Process?

摘要

The efficiency of the metallurgical process can be increased by the incorporation of mineralogical data during the process. Moreover, mineralogy plays a key role in the efficiency of biomining operations and is necessary to predict the formation of acid mine drainage. Decision making in mining operations is currently mainly based on element concentrations (e.g. ore grade, cut-off, acid base accounting) assuming mineral associations of these elements (often with or without sufficient mineralogical data). This can lead to inefficiency of the mining process and environmental problems. Standard prediction methods for acid mine drainage are not accurate enough and there are no methods available, for example, to predict the stability of mine waste under reducing conditions as would apply to submarine tailings disposal (STD), a tailings management strategy that is seeing a revival in the mining industry. To overcome these problems, advanced methodologies have to be applied to characterize newr ore deposits before exploitation starts. This approach gives the opportunity to design optimized processes for efficient metal recovery of the different mineral assemblages in an ore deposit and at the same time to minimize the future environmental impact and costs for mine waste management. Additionally, the whole economic potential is evaluated including strategic elements such as rare earth elements (REE). The methodology should integrate high-resolution geochemistry by sequential extractions and quantitative mineralogy in combination with optimized kinetic testing (oxidizing or reducing conditions, depending on the final waste deposition environment). The resulting data set allows the identification of units with similar geochemical behaviors in the ore deposit and to predict the behavior of each economically or environmentally relevant element throughout the mining process and in the final deposition site.