Comparison of Productivity When Running Filled, Near-Empty, or Flow-Through Orepass Using Discrete Event Simulation

Abstract

Ore passes are often the main part of sublevel caving transportation systems, and they use gravity to move material to lower levels in the mine. During operations, the ore pass structures are exposed to the risk of stoppage and failure, leading to a long-term reduction in operational capacity and affecting productivity. The failed ore passes can be restored or rehabilitated, but the rehabilitation cost is normally high and the time to restore is usually long. To minimize disturbances and stoppage of the ore pass, alternative strategies should be considered. The appropriate design and operation of an ore pass is crucial. Therefore, this study compared running ore pass systems in a filled, near-empty, or flow-through manner using discrete event simulation. The aim was to compare the ore pass operational performance and impact on reaching the daily and 90-day production targets of 76.4 Ktonnes and 6.9 Mtonnes, respectively. The results showed that running the ore pass in flow-through mode, filled manner, and near-empty manner achieved 96%, 80%, and 81% of the production target, respectively. In mining operations where ore pass systems are used to transfer material, running them in a flow-through mode can ensure higher production and fewer hang-ups, as it lessens the chance of blocks arching over a chute throat and leads to less blasting.