Integrating Work Index into Mine Planning at Large Scale Mining Operations
CIM Edmonton 2004
Charles Pelley, Takis Katsabanis, Shadan Kelebek,
Mine planning and mineral processing optimization are usually treated as two unconnected problems, especially at open pit and panel caving mines where the cut-off grade is practically the only variable optimized and analyzed for planning proposes.
Using existing planning tools the output is a reserve consumption strategy privileging higher grades. With the earlier consumption of the highest grades, every year produces incomes which are closer to the cost and potentially even below cost. However, there are other ore characteristics that can make the operation more or less profitable?
A new methodology has been developed, incorporating the grinding and flotation relationship into the mining economic models for the simultaneous analysis and optimization of the throughput-work index-recovery relationship through changes in the mining limits, sequence and redefinition of the reserve consumption strategy.
A mine-site that implements this new planning strategy, can expect to increase the NPV from 5 to 20% depending of the actual operational settings.
Two case studies have been developed, showing how the inclusion of the work index in the economic model changes the phase and mining sequence in an open pit mine and the caving sequence and the optimum column height in a panel caving mine.
Mine planning, Open pit, Mine to mill, Net present value, Work index, Panel Caving