Equipment size effects on open pit mining performance

Abstract

This paper discusses the exploitation of economies of scale in open pit mining through the use of increasingly larger equipment. It presents a method adopted to evaluate the impact of increased scale on operational performance factors. The work identifies equipment size sensitive variables (ESSVs) in the mine design process that affect the performance of the production process. Data from a set of case studies show that the ESSV influence extends beyond mine production to encompass milling performance, environmental footprint and community impacts. Some ESSVs (such as reliability, tyre costs and productivity) are shown to be related to the current state of equipment technology and their effects are therefore comparable for different mines. Other ESSVs relate to the mine and deposit characteristics; their effects therefore vary from mine to mine. A detailed analytical approach, developed to model the impact of ESSVs, suggests that for truck/shovel operations, the industry may be approaching a situation of diseconomies of scale.

Keywords:

• Equipment size
• Maintenance
• Economics of scale
• Mine planning
• Equipment selection

Acknowledgments

We thank Professors Laeeque Daneshmend and Garston Blackwell from Queen's University, and Malcolm Scoble from the University of British Columbia for their input, advice and support during this research. We also would like to thank personnel from the Canadian mining industry who kindly helped us by providing data during this research.