Modelling and simulation of the grinding circuit at 'El Pilon' Mine

The grinding operation in a ball mill is widely used in comminution. This process is extremely capital and energy intensive process and at the same time it is notoriously inefficient. Therefore, simulation can be used as a convenient tool in studying the behaviour and performance of grinding circuits by facilitating the evaluation of various scenarios and identification of optimum operating conditions. This paper presents how these modern simulation techniques are applicable to a grinding circuit using JKSimMet computer package. A grinding model developed at 'El Pilon' mine using JKSimMet (Version 4) was used to simulate three different milling designs. The objective of these simulations was to investigate a new design of the grinding circuit with an additional ball mill to increase both grinding throughput and fineness. The simulation results highlight that two closed grinding circuits in series are more appropriate to achieve these targets. Surveying the implemented grinding circuit validated the JKSimMet simulation results. An increase of grinding throughput from 600 tpd to 800 tpd was achieved in the grinding circuit in serie as well as an increase of the grinding fineness from 57% to 75% passing 75 mm. This case study shows that JKSimMet can be used to design grinding circuit accuracy and highlights that this computer simulator is a powerful tool in the optimisation of comminution circuits