Pumping sustainably - power and water consumption in mineral processing plants: someone should care

Pumping sustainably stems from the recent Intergovernmental Panel on Climate Change (IPCC)report. In the mineral processing sector, comminution processes are attracting an increasing interest to achieve sustainability. Comminution accounts for 4 per cent of total global energy consumption. A typical mineral concentrator plant dedicates, on average, 50 per cent of the total concentrator energy to comminution processes. While pumps, the second most common machine in the world, are considered ancillary machines with small individual footprint- be it energy, cost, or water-their numbers greatly amplify their cumulative impact. Collectively, pumps account for 15 per cent of global consumption of the world's electricity, and on average mine site total pump-motor energy consumption is estimated to be 25-32 per cent. Despite the abundant literature on pumps, no holistic review on their sustainable deployment has been found. Therefore, this paper investigates the energy and water consumption by pumps in mineral processing plants during three phases: the design phase, the installation and commissioning phase, and the mature operational phase. From the case studies - gold, copper, and iron ore operations - it is found that pumps consume 18-28 per cent of the plant energy and 7 per cent of the site water. Additionally considering pumps on an individual basis leads to short-term capital focus in the design phase and does not consider aggregated energy and water usage of all pumps. This leads to using conservative safety margins and not considering optimum selections to reduce power and water consumption. It is followed by evaluating the operating practices affecting efficiencies and providing recommendations. Furthermore, digitalisation as a means of efficient monitoring and performance tracking is also introduced. The functional performance of pumps is critical to each mineral processing plant and their overall analysis from the design, selection and operation can yield substantial savings and benefits. With the increasing awareness of climate change, a strong decarbonisation of the global economy, by continued emphasis on critically assessing methods and operations, is necessary.