Unearthing a sustainable mining future

Professor Megan Becker delivered her inaugural lecture at the University of Cape Town (UCT), addressing sustainability within the mining industry. Her lecture, titled “Why Minerals Matter: The Role of Mineralogy in the Pursuit of Sustainability” explored the essential but complex relationship between mining and sustainability, particularly in the context of a low-carbon future.

UCT’s vice-chancellor (VC), Professor Mosa Moshabela, opened the evening by reflecting on the significance of inaugural lectures: “Inaugural lectures mark the ascent to full professorship, the highest academic rank. It provides universities with an opportunity to celebrate the achievements of the academics. They also, importantly, provide an opportunity for the inaugural lecturer to share his or her insights into their scholarly work in a manner accessible to us, the broader audience.”

The dean of the Faculty of Engineering & the Built Environment, Professor Alison Lewis, also praised Professor Becker for her commitment to addressing critical issues within the mining industry and for leading efforts toward more sustainable mining practices.

The paradox of mining and sustainability

Becker acknowledged the inherent contradiction between mining and sustainability. Mining, an industry often associated with environmental degradation, is paradoxically crucial for the materials needed in renewable energy technologies, such as electric vehicles and solar power.

Metals like lithium, copper, and nickel are essential components of clean energy systems, and the extraction of these metals is necessary to meet the world’s growing demand for low-carbon solutions.

“We need mining to achieve a sustainable future.”

“Mining and sustainability often appear to be at odds with one another, but the reality is that we need mining to achieve a sustainable future. Without these critical materials, we cannot transition to renewable energy or build the infrastructure needed for a low-carbon economy,” Becker said.

Her research focuses on how mineralogical knowledge can help the mining industry operate more sustainably. By understanding the characteristics of the minerals being extracted, mining companies can develop more efficient processing methods, reduce waste, and minimise environmental harm.

South Africa’s mining legacy

As a South African researcher, Becker is acutely aware of the country’s mining legacy. South Africa has long been a global leader in extracting valuable minerals – particularly gold and platinum – but this has come at a significant environmental and social cost. In addition to the environmental damage caused by mining operations, South Africa has faced public health challenges, including silicosis, a lung disease caused by exposure to fine mining dust.

Becker addressed these challenges in her lecture, pointing to the need for innovation in the mining industry. She shared examples from her research on platinum group elements and gold mining, highlighting how mineralogical analysis can inform more sustainable extraction techniques. By optimising the extraction process, mining operations can reduce energy consumption, lower costs, and generate less waste.

Her case studies illustrated the potential of mineralogical data to inform decision-making in mining. For instance, by understanding the composition and behaviour of specific minerals, companies can adapt their processing methods to recover more valuable metals while leaving behind fewer hazardous materials.

Managing mining waste

One of the most significant issues Becker tackled in her lecture was mining waste management. Mining generates vast waste material, including tailings, which are often stored in large dams. These tailings can pose environmental risks, such as acid mine drainage, which occurs when sulphide minerals in the waste react with water and air to produce acidic run-off that can contaminate nearby water sources.

Becker’s research has explored ways to mitigate these risks by “valorising” mining waste; that is, finding new uses for waste materials. She explained that in many cases waste material can be repurposed for construction projects or other industrial uses, reducing the need for new raw materials and preventing the environmental hazards associated with waste storage.

“In many ways, mining waste is an untapped resource. By finding ways to repurpose this material, we can reduce the environmental impact of mining and create new economic opportunities,” she explained.

Becker also stressed the importance of minimising the production of waste in the first place. Through more precise mineralogical analysis, mining companies can tailor their extraction processes to recover as much valuable material as possible, reducing the amount of waste generated. She emphasised that waste minimisation and valorisation are key strategies for making the mining industry more sustainable in the long term.

The role of mineralogy in future technologies

As the world continues to transition to a low-carbon economy, Becker believes that mineralogy will play an increasingly important role in the development of new technologies. Renewable energy technologies, such as wind turbines and solar panels, require significant amounts of critical metals, and the demand for these materials is only expected to grow.

Becker explained that mineralogical research can help mining companies unlock new sources of these critical metals by improving the efficiency of extraction processes. For example, her research has shown that innovative grinding techniques, such as vertical roller mills, can significantly reduce energy consumption during the ore processing stage, making mining operations more sustainable.

“By investing in research and embracing new technologies, we can ensure that mining continues to meet the world’s needs while minimising its environmental impact.”

She also discussed the potential for recycling to play a larger role in meeting the demand for critical metals. While recycling can help reduce the need for new mining operations, Becker noted that it is unlikely to meet global demand on its own. Mining will still be necessary, and mineralogical research will be essential for ensuring that mining is done in the most sustainable way possible.

A call to action

In her concluding remarks, Becker called for a greater emphasis on sustainability within the mining industry. She argued that while mining is often seen as inherently harmful, it is possible to mitigate its negative impacts through innovation, research, and responsible management.

“Mining is not going away, but we have the tools and the knowledge to make it more sustainable. By investing in research and embracing new technologies, we can ensure that mining continues to meet the world’s needs while minimising its environmental impact.”