CANADIAN METALLURGICAL QUARTERLY, vol.59, no.1, pp.116-124, 2020 (SCI-Expanded)
Many studies investigated the effects of grinding aids on mechanical and breakage properties of particles, as well as the flowability of ore-water slurries in wet grinding mills. Only recently, it was showed that grinding aids can promote grain-boundary fracturing. This paper aims to observe the effects of water pretreatment on chromite liberation, to underlie some reactions between water and chromite samples which promote the liberation of coarse chromite grains, i.e. the grain-boundary fracturing. For the purpose of this study, two different chromite ore samples were initially pretreated under water at different sets of pH, temperature and pretreatment time. Then, the untreated and pretreated samples were broken in a drop-weight tester (J/g). Finally, the grade-recovery plots in the selected progeny size fractions of the untreated and pretreated samples were compared. The results show that the hydrolysis of ore samples in 15 min of pretreatment improves the grain-boundary fracturing. The results also suggest that mineral carbonation may be beneficial for chromite liberation.