Application of an exergy approach to understand energy demand of mine water management options

Water is required for mining and mineral processing operations. In recent years, the mining industry is facing increasing water demand and increasing competition with other water users. Hence, mine water systems need to be well managed to ensure water is reliably available for mining operations. Energy is required for almost all water processes, such as pumping, treatment, cooling and heating. The management of a mine water system is related to energy use. For strategic mine water management, information about the energy demand directly related to different water management options is usually required to assist in the decision-making process of selecting suitable water management options. This research presents the application of an exergy analysis technique named 'Physical Hydronomics' to show critical factors affecting the energy demand of water management options. The analysis identifies focus points where additional energy demand can be reduced or avoided when upgrading a water system. At the same time, energy demand of different water options isalso quantified. The method is demonstrated by assessing the energy demand of three water desalination options of a coal mine. The aim of introducing these water options tattle mine is to improve water use efficiency. The exergy analysis technique generates exergy profiles of water flows and presents critical factors related to the energy demand of water flows. At the end of the analysis, total exergy demand of each of the three water desalination options is estimated. (C) 2014 Elsevier Ltd. All rights reserved.