A hierarchical open-pit mine production scheduling methodology linking the optimal strategic open pit mine plan to the optimal medium-term production schedule is presented. The main objective of this paper is to develop, implement, and verify a mathematical programming framework for the optimal medium-term open-pit mine production scheduling using Mixed Integer Linear Programming (MILP). The objective of the medium-term mine production schedule is to minimise operating costs, including waste rehabilitation, processing, mining, haulage, and rehandling costs. To verify the proposed hierarchical model, an iron ore case study is presented. The results are interpreted and analysed to verify the applicability of the model in terms of mining practice. The main contributions of the medium-term production scheduling optimisation model are: multiple destinations modelling including stockpiles, processing plants, and waste dumps; decision making on selection of routes/ramps to minimise the haulage costs; and modelling stockpiles using MILP.
Keywords: mine production scheduling, long term, medium term, stockpiles, optimisation, MILP, mixed integer linear programming, CPLEX