Evaluation of belt conveyor and truck haulage systems in an open pit mine using life cycle assessment

CIM Bulletin, Vol. 4, No. 5, 2009

K. Awuah-Offei, D. Checkel, H. Askari-Nasab

-------------------------------------------------------------------------------------------Click the "Download this article" link to view technical paper in PDF format.------------------------------------------------------------------------------------------- The environmental impacts of mining operations have become more important in recent times. Accordingly, these impacts are gradually becoming an important factor in the choice of equipment for unit operations. In material handling operations in mines, belt conveyor systems are generally considered to be more environmentally friendly than off-highway truck systems. This view is confounded by the environmental impacts associated with the use of the two material handling systems. Life cycle assessment (LCA) of operations examines the environmental impact of systems over their entire life cycles with respect to capital and operating impacts. In this paper, LCA methods are used to evaluate the environmental impacts of belt conveyor and truck haulage systems in a hard rock open-pit gold mine. Also, using global warming and acidification potential impacts, the paper tests the hypothesis that belt conveyor systems are more environmentally friendly than are truck haulage systems. The results show that truck haulage systems have 300% more potential acid rain impact on the environment, while belt conveyor systems have 336% more potential global warming impact on the environment. Using natural gas instead of coal to generate electricity at power generating stations reduces the impact of the belt conveyor option. A complete assessment of the accuracy of the initial hypothesis is not possible until the relative importance of the selected stressor categories (global warming potential and acidification potential) are thoroughly examined. This work introduces the concept of LCA in the equipment selection process in mining. Given current trends in environmental regulation research, LCAs can assist mine planners prepare environmentally responsible development plans, which will better reflect environmental standards.

Keywords: Life cycle assessment, belt conveyor, off-highway trucks, surface mining