Assessing the specific energy for two iron ores using steel, ceramic and mixed steel-ceramic ball charges in fine grinding

Grinding is the final stage of comminution and has a significant impact on the subsequent concentration processes. However, this is a costly step due to the high consumption of energy, balls, and liners. In recent years, there has been a substantial growth in demand for high performance grinding media due to the increasing need for effective and sustainable applications in the mining sector. This study evaluated the specific energy consumption of three grinding media charges: steel, ceramic, and mixed steel − ceramic, using two fine iron ore samples. The Grinding Kinetics (GK) approach was first applied to provide the basis for the subsequent specific energy calculations. The Size-Specific Energy (SSE) and Signature Plot (SP) models were then employed to estimate and compare grinding efficiency under each condition. The results showed that mixed steel − ceramic charges improved grinding efficiency compared to steel alone, while exhibiting comparable performance to fully ceramic media. Despite similar energy expenditure, the mixed charge achieved finer particle sizes in shorter grinding times. The study also showed distinct kinetic responses between the two ore samples, reflecting differences in their feed size distributions and textural characteristics. These findings suggest that mixed media can provide both operational and energy advantages.