Title: Economic evaluation of materials handling systems in a deep open pit mine

Authors: Kesegofetse Bumo-Motswaiso; Raymond S. Suglo

Addresses: Department of Mining and Geological Engineering, Botswana International University of Science and Technology, Plot 10071, Palapye, Botswana ' Department of Mining and Geological Engineering, Botswana International University of Science and Technology, Plot 10071, Palapye, Botswana

Abstract: Materials handling constitutes a large portion of the costs of mining operations. Therefore, the system chosen must be cost-effective yet meet the production demands of the mine. In this paper, unit haulage costs, economic risk and sensitivity analyses were conducted to determine the optimal way of handling materials in a deep open pit mine between the traditional truck-shovel haulage system (TSHS) and in-pit crushing and conveying (IPCC) haulage system. The results show that the IPCC haulage system has lower unit costs than the TSHS. The NPV of IPCC system is US$ 15.09 × 10⁹ while that of the TSHS is US$ 14.64 × 10⁹; the DPP of the TSHS and IPCC systems are 2.94 months and 2.13 months, respectively, while the IRR of the TSHS and IPCC systems are 147% and 185% respectively. As the NPVs of both systems are positive, with very short DPPs and high IRRs, the systems are considered to be economically viable. However, the IPCC is considered more economically viable than the TSHS. The NPV of IPCC is less sensitive to variations in the input variables compared to TSHS.

Keywords: truck-shovel haulage system; TSHS; in-pit crushing and conveying; IPCC; net present value; NPV; discounted payback period; DPP; internal rate of return; IRR.

DOI: 10.1504/IJMME.2022.124144

International Journal of Mining and Mineral Engineering, 2022 Vol.13 No.1, pp.37 - 48

Received: 27 Nov 2021
Accepted: 17 Mar 2022
Published online: 14 Jul 2022 *