Evaluation of mine waste characterization to identify opportunities for optimizing project economics using fragmentation analysis

Abstract

ABSTRACT As metal mineral resources get depleted over time, there is a need to recover metals from ores of lower grades and waste. Mining wastes are largely characterized using physical and mineralogical heterogeneity properties. There is variation in the geochemical properties with different grain sizes, thus, different metal recovery potential. The research evaluated mine waste characterization and identified opportunities for optimizing project economics using fragmentation analysis. This study linked petrographic, compositional and quantitative mineralogical analyses with fragmentation data resulting from conventional mechanical communition of mined-out waste rock. The results improve the understanding of what grain sizes are optimal for metal recovery from the waste rock and established that environmental threats can be mitigated by removing fines from waste. The economic metals including Ni and Cu sulphides are predominantly held in pentlandite and chalcopyrite within the rocks. Maximum liberation and metal recovery are in the finer grains.