Metodologia para utilização da energia específica de cominuição no planejamento de lavra

Abstract

Strategic mine planning is critical to the success of a mining project. Global optimization is a methodology derived from Direct Block Scheduling (DBS), presenting formulations capable of presenting the final pit and mine sequencing in a single step. In the literature, there are few studies that consider the geometallurgical variable comminution specific energy in mine planning. The use of this variable allows greater reliability in decision making, as the rock hardness influences the operational costs. The research developed a methodology for the use of the comminution specific energy. Six scenarios were developed: A1, A2 and A3, which used the Marvin block model; B1, B2 and B3, built using a model owned by BNA Mining Solutions. A1 detailed strategies to maximize the Net Present Value (NPV) and meet the operational constraints of the deposit. The A3 scenario obtained gains in NPV and production of 9.66% and 5.18%, respectively, compared to A2 due to ore stockpiles and fixed mass movement for different periods. The B2 scenario, that considered geometallurgical variables, found lower NPV and production results in, respectively, 13.57% and 6.97% were compared to scenario B1, where such variables were not taken into account, resulting in low reliability and adherence to operational reality. On the other hand, B3 obtained gains of 5.84% in NPV and 5.45% in production compared to B2, due to the use of ore stockpiles and fixed mass movement ranges in certain periods.