It is widely known that the mining industry is one of the largest contributors to global greenhouse gas emissions while also contributing to many other types of environmental pollution such as contaminating waterways with mining effluents, releasing toxic compounds to the atmosphere, and disrupting fragile ecosystems. This has been the case for a long time, and the Canadian mining industry is no exception, but why is there resistance to change, and how can the mining industry reverse the trend and reduce its environmental footprint?
A Look Back at the Mining Industry
Historically, the high profit margins enjoyed by the mining industry have been a motivating element in their inaction. With little financial incentive to improve efficiency, they have maintained the status quo of exploiting proven but aging processing technologies. However, in the face of increasing societal and governmental pressures, many companies in the mining industry have undertaken the task of reducing their environmental footprint.
While it would seem obvious that certain approaches could be easily implemented to help towards this goal, such as the use of renewable energy sources to power mining operations, the reality is not quite so simple, and the high power demands of this type of operation imply that the intermittent nature of the power created by many renewable sources such as wind and solar is less than appropriate. Other options exist, which could be more appropriate, such as more eco-friendly combustible sources, including biochar, hydrogen, and pyrolysis oil, but these are not without their challenges, as the use of less well-understood combustibles can create major safety issues. For example, injecting hydrogen into an existing traditional combustion process could increase that process’ energy output significantly without increasing CO2 output, but this can lead to significant risks, as hydrogen molecules are small enough to infiltrate the metal walls of furnaces, thus weakening the material through a process called hydrogen embrittlement and creating a potential explosion risk.
Increasing the efficiency of mining operations is also a popular way for mining companies to reduce their environmental footprint. For this, mineral ore purification is the major axis of improvement, as processes that can increase the purity of an ore stream after initial treatment steps can reduce the need for energy intensive purification steps such as smelting or electrolytic treatment. These initial treatment steps often involve some sort of physical separation method such as floatation, where a combination of density-based gravity separation and chemical adjuvants are used to separate the ore of interest from any impurities. While these are known processes that have been used for a long time, little improvement has been made to them over this time, and thus the opportunities for improvement are significant, with the main goal of better understanding the relationships between key process parameters like ore granularity, the nature of the chemical adjuvants, and the resulting degree of separation. However, a significant part of the associated development efforts have to be targeted towards the environmental impact of these improved processes, for example, novel chemical adjuvants can have negative impacts on the surrounding environment if they are present in the process’ effluents, implying that special care has to be taken to not only assess the impacts of the changes brought to the process but also to develop special mitigation techniques to properly manage these impacts.
Finally, the idea of properly measuring the environmental impact of all parts of mining operations has also become a focus within the industry. These types of operations are often located in remote areas and surrounded by pristine wilderness, and in the past proper care was not taken to minimize mining’s impact on surrounding ecosystems, but as part of this recent push to minimize environmental footprints, development work has been undertaken to not only develop sampling and analysis techniques to properly evaluate the impacts of current operations, but also novel approaches to measure and mitigate historical contamination.
Ultimately, while our need for resources will keep growing, recent and future efforts in mining which aim to minimize the environmental impacts of their operations point towards a more sustainable future for this industry.
Companies that are innovating in this sector are likely to be eligible for several funding programs including government grants, and SR&ED.
