Strategic mine planning is the process of determining the configuration that will optimise project objectives. These objectives may be value-based, risk-based or based on some other goal, depending on the company and the situation. 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, sub-optimal mine plans are often produced. The ability to model and optimise key decisions simultaneously (for both open pit and underground projects), in attempting to achieve greater value, is investigated in this thesis. The optimisation models created through this research employ mixed integer programming (MIP). The most appealing property of MIP is the guarantee of finding the optimal solution to the optimisation model, subject to computer hardware constraints. Hence, solutions are able to be compared consistently. Some of the areas where advances are made include time cost modelling, cut-off grade and stockpile optimisation for open pit operations, and schedule and cut-off optimisation for underground operations. This thesis describes methods to enable the efficient determination of optimal mine plans for a given project configuration. Case studies show that the methods developed can lead to meaningful increases in value and reductions in risk.
|Qualification||Doctor of Philosophy|
|Publication status||Unpublished - 2009|