O teor de corte como um output do planejamento estratégico para otimizar a geração de valor. Um estudo de caso

Abstract

The cut-off grade, although being usually considered to be just another trivial step in the process of strategic planning in a mine, is an element of enormous importance when looking into a real operation or a mine project under a value generation or maximization of value generation point of view, because it carries in itself the power of classifying a volume of rock as ore or waste. Traditionally, from a series of cost parameters and assumptions cut-off grades are estimated or modelled and such grades are then used to delineate orebodies for which designs, and extraction sequences are developed considering mining, processing, and productivity constraints. Through this classic approach, the cut-off grade is part of a set of entries or inputs that culminate in the strategic plan. This work defends the idea that the cut-off level should be treated as an output factor of the strategic planning and as such it is under the control of the company in the definition of its corporate strategy. In order to support the idea, it proposes a case study using real operation data in which it compares the generation of value using the traditional approach – calculated by the method of Net Present Value (NPV) by discounted cash flows – with the generation of value when using the optimization of cut-off value to maximize the NPV.