Investigating of the effect of ore work index and particle size on the grinding modeling of some copper sulphide ores

The aim of this research was to apply Box–Behnken experimental design and response surface methodology (RSM) for grinding modeling of some copper sulphide ores. In the present work, the effects of some key grinding parameters such as ball size (20–40 mm), grinding time (10–30 min), solids content (65–80%), and also ore work index (12–15.4 kWh/t) on the grinding of some copper sulphide ore were investigated. Product 80% passing size (d80) was defined as process response. Grinding experiments were designed and executed by a laboratory ball mill. These experiments were conducted on two feed sizes (480 and 1000 μm). Predicted values of response obtained using model equation were in good agreement with the experimental values (R2 values were 0.997 and 0.996 for d80 of 480 and 1000 μm feed sizes respectively). The effect of parameters was explained as bellow: The d80 of product was decreased with increasing solids content from 65 to 71%. The relation between work index and also ball size with d80 were linear over the studied range. The effect of ball size and also grinding time on d80 was more at lower values of solids content compared to higher values of solids content at studied levels. The effect of grinding time on d80 was more at lower values of work index rather than higher values. There was no effect of feed size on the order of effective parameters but increasing feed size had effect on the interaction of variables.