LAUSR

A sulfide copper ore was crushed to 100% passing 3.36mm, and then the crushed product was ground by bed breakage in a piston- die cell or ball mill grinding to 100% passing 250μm. The particles size analysis results of the grinding products showed that the bed breakage compares to ball mill produced a finer product. Liberation analysis of the products in eight size fractions showed chalcopyrite in the ball mill product was more liberated compared to the bed breakage product. The overall percentage of chalcopyrite liberation in the ball mill product was 1.82% higher than the bed breakage product. Using the analysis of scanning electron (SEM) images, the shape properties of particles in the breakage products were examined. It was found that particles were produced from the bed breakage have circularity and roundness more than particles produced from the ball mill and the ball mill particles are more elongated. Micro-flotation tests results showed the Cu recovery and separation efficiency for the ball mill product were respectively 11% and 15% higher than the bed breakage product. This better metallurgical performance was attributed to the bed breakage product was finer, chalcopyrite was more liberated in the ball milling product and particles in the ball mill product had less circularity and roundness. The results of this study indicate that, unlike many previous studies, bed breakage did not increase mineral liberation and improve the performance of the flotation process.