What is the optimal pushback dimension for Sishen mine that will complement its current mining fleet?

Abstract

Sishen mine has been an operational mine for over 70 years mining the orebody by means of pushbacks. There has never been a study done on the operation to determine the optimal pushback width that will be suited with the equipment that will be used at the operation. This was never seen to be a problem in the past due to high iron ore prices and mining lower stripping ratio areas so the Life of Mine (LOM) has never indicated an ore deficit until now. This has triggered the company to be forced to interrogate the current pushback widths and to fully understand with the mining fleet that is being used at the mine what the optimal pushback width would be. Research on pushback configurations primarily examines geometric limitations, and there are limited studies on determining the ideal pushback dimensions. The assumptions regarding production rates incorporated into a company's long-term strategies typically rely on historical data, with slight annual enhancements factored into the outer years. If historical data rates are not fully grasped, their application can result in misleading conclusions. Earlier research determined optimal mining width, mainly by optimizing pushback width based on tonnage, ignoring specific equipment. This leaves a gap that once the pushback width has been identified, then what mining fleet should be deployed in that pushback to ensure that the pushback will be mined optimally. A lack of precise comprehension may lead mining firms to acquire machinery that does not match their pushback specifications, resulting in suboptimal fleet utilization. This research focuses on the Sishen mine to analyse the existing mining fleet and determine feasible pushback widths, creating practical designs. Evaluating the designs with a schedule and cash flow analysis to determine the best mining width based on NPV and IRR. Mining enterprises around the world can apply a consistent approach to identify the most effective pushback width that aligns with their machinery capabilities. This strategy of designing pushback widths for a specific mining fleet will be particularly beneficial for new mining ventures, yet it remains applicable to ongoing mining operations as well.