### Chapter M MODELLING, SIMULATION, OPTIMIZATION

permits new models to be added for simulation of various unit operations (King 2001). 2 THEORY SAG mill modeling In MODSIM, one of the simulation models used for a SAG mill unit is SAGT (SemiAutogenous Grinding with Trommel) model. In this model, a SAG mill with a trommel screen at mill discharge is modeled using the