Open pit optimisation – modelling time and opportunity costs

Abstract

Strategic mine planning is the process of determining the configuration that will optimise project objectives. Current methods for ensuring that objectives are optimised, for a given project configuration, contain a number of limitations. In particular, the strategic mine planning process for a given configuration is often completed by the sequential optimisation of key decisions. This approach does not allow for relationships between decisions to be measured accurately. As such, suboptimal mine plans are often produced. The ability to model and optimise key decisions simultaneously, so as to achieve greater value, is investigated in this paper. Some of the areas in which significant advances are made include time cost modelling, cutoff grade and stockpile optimisation for open pit operations. A case study was used to benchmark the proposed model against a marginal cutoff grade scheduling method, resulting in significant net present value increases.

Enumeration optimization of open pit production scheduling based on mobile capacity search domain

“…Therefore, some researchers try to find solutions in the construction of mathematical model forms (mainly constraints) or solving algorithms (usually by feat of approximate algorithms) to boost the solving speed [36][37][38][39][40][41][42] . Increasing the decision-making unit to reduce the quantity of variables and constraints is a more common way, such as combining the modules in the deposit model into a "unit tree" as the decision unit in optimization or taking steps or panels as the decision unit 37,[43][44][45][46][47][48][49][50][51] . However, due to the low scheduling accuracy (or resolution) in enormous decision units, the results are significantly different from the optimal plans, which also reduces the practicality of the results 47,49,52,53 .…”