Improving block caving production by incorporating operational risks in short-term scheduling

Abstract

In caving mines, productivity and safety can be affected by geotechnical hazards, such as rockbursts, inrushes, collapses, and air blasts. These operational risks decrease the availability of drawpoints and impact compliance with the short-term mine production schedule. In these cases, the mine production schedule has to be updated, modifying the amount of mineral extracted from the drawpoints and often producing sub-optimal results. This study proposes a new methodology to incorporate operational risks in the short-term scheduling process in Block Caving mines. The proposed methodology employs a logistic regression model to define the drawpoints at high-risk and a multi-objective optimization model that determines the daily production to meet the grades and tonnage targets, and at the same time, minimize the operational risk. The proposed methodology is implemented in a case study in which the methodology is shown to reduce tonnage at high-risk of experiencing an event of inrush of fine material while meeting the production targets. The results of the present work demonstrate that it is possible to integrate operational risk in the short-term production scheduling of Block Caving mines, allowing the planner to modify the hierarchy of objectives to adapt to the mine's requirements.