Energy Efficiency in Mining
In terms of energy and water availability, a collaborative and multidisciplinary approach should be used for the construction of a flexible production chain, capable both of absorbing the variety of the upcoming challenges and adapting to current needs of society that require technology and hence metals as raw materials.
Undeniably, energy efficiency is among the primary challenges that the mining industry has to manage and incorporate, along with the permanent need to increase operational productivity. Within this context, many questions arise, such as: What do we understand by energy efficiency? Are we doing enough to move towards a more energy efficient industry? And: Is the use of renewable energy a way to achieve efficiency? These enquiries aim at challenging the way metal production is currently managed and reconsidering what was planned for the near future, calling on to our intrinsic capacity to adapt to complex and challenging scenarios.
The growing global demand for metals, the strong impact generated by the constant decrease in ore grades, and the shortage of water resources in mining areas has metal producers diversifying their processes, searching for more energy efficient paths without jeopardizing the quality of their products. To achieve this objective, it is inevitable to involve technological advances and research developed nationally and internationally. These advances make the challenge more manageable, expecting to achieve day-to-day production that is more responsible in the use of essential resources like water and energy.
Does the use of seawater in mineral processing and increased utilization of renewable energy sources make us more efficient? Without a doubt, the inclusion of these alternatives in current processes has meant great progress for metals production and for environmental management. However, using renewable energy does not necessarily generate greater efficiency. Independent of the energy or water sources used, having an efficient mining process involves the decision and responsibility of using only what is necessary to convert raw material into marketable products, that comply with market quality standards and with minimum intervention within the larger context they are developed.
This scenario enhances the need for precise monitoring of the involved processes, as well as the adequate control of critical variables that determine their performance. Together, it is important to have a flexible process and a timely response for imminent fluctuations brought by variability in mineral deposits, considering the great diversity of physical and chemical properties that determine their behaviour when processed. This is where issues such as digital transformation and predictive modelling become more relevant, seeking to implement technological developments focused on correctly controlling and monitoring the general process, and particularly, energy-intensive operations, such as grinding.
SMI-ICE-Chile along with researchers from the Sustainable Minerals Institute at The University of Queensland, Australia, and in collaboration with national research centres like AMTC (Advanced Mining Technology Centre) from Universidad de Chile, have carried out research projects in different mineral concentrator plants in Chile. Our work includes site visits to inspect facilities, interviews with staff in control rooms, and meetings with the leads of the involved areas, as a way to strengthen our understanding of the process and involvement with the people in charge.
Visit to the Huasco pellets plant, August 2019, Energy Efficiency Project for CAP Minería
We look for sources of inefficiencies and aim at being aligned with the company objectives, as well as generating recommendations and alternatives that may be applied and implemented in the operation, without affecting the quality of the products. The work is complemented by a statistical analysis of operational variables to determine the actual variability or stability of the plant operation. Likewise, simulations with specialised software are used to look for scenarios that turn the operation into a more efficient process. Literature reviews and benchmarking focussed on similar processes also help build the foundations of the resulting suggestions.
This type of work requires a thorough and holistic understanding of processes and the current state of the art at each plant, because our projects strongly correlate performance evaluations with the identification of opportunities that allow for greater efficiency. Likewise, they link to the effectiveness and precision that both the implemented instrumentation and control systems have in order to capture, process and interpret critical information that defines performance and stability of the production.
We consider that to move forward in this direction, it is necessary to broaden our vision and opt for a less conservative position, providing room for innovative points of view and alternatives capable of bending the deep-rooted paradigms established as part of the traditionally more conservative mining culture.
Left to Right: José Ojeda (SMI-ICE); Luis Diaz (CAP); Gustavo Ceballos (AMTC); Norelys Aguila (AMTC); Romke Kuyvenhoven (SMI-ICE); Solange Vera (SMI-ICE); Marcin Ziemski (SMI-JMRC); Rodrigo Martinez (CAP)
Much like the growing existence of new difficulties in mining, and even when it is possible to provide solutions to imminent challenges, in terms of energy and water availability, as industry we have to work collaboratively and in a multidisciplinary environment for the construction of a flexible chain of production, capable of creating an absorbing effect for the upcoming challenges, and to adapt to current societal needs, highly dependent on technology and, in consequence, of metals.