The push toward a post-carbon economy and society is rapidly gathering pace as industry and governments seek to address critical problems associated with fossil fuel exploitation. Several industries are currently adopting new technologies and working practices with the aim of decarbonizing operations.
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Accelerating the electrification of key industries and phasing out fossil fuel-based energy generation in favor of renewable energy sources are essential areas of progress. However, this shift is creating new challenges. This article will explore how decarbonization could increase mining waste and how this problem can be mitigated.
Toward a Post-Carbon Future
As the effects of climate change are becoming more apparent, governments and companies are investing heavily in new technologies. Completely phasing out fossil fuels, a major driver of climate change, is the main focus of several key players within industry and government.
Multiple governments and international bodies have agreed to phase out fossil fuel use completely over the coming decades. However, to do so, the energy demands of a rapidly growing world population must still be satisfied.
Several renewable energy technologies have seen growing deployment in recent decades, including photovoltaic solar cells, wind turbines, and geothermal power plants. These require new technologies and materials to be developed, consequently accelerating progress in multiple fields.
Batteries, fuel cells, and supercapacitors have emerged as forerunners in green energy storage research, which provide opportunities for companies to accelerate the move toward full electrification. Hydrogen has received widespread attention as a viable alternative to fossil fuels for energy production and fuels.
The Rapid Development of Batteries
Batteries, one of the leading technologies currently driving the electrification of key industries, have undergone a revolution in recent years as researchers develop more efficient, safer, and lower-cost solutions. The battery market has grown exponentially to meet the demands of the industry.
Electric vehicles (EVs) demand cheaper, more durable, lighter batteries with enhanced performance and efficiency. Electronics manufacturers need batteries with longer lives and increased durability and safety. Wearable technologies used in the biomedical field require ever-smaller batteries.
Increasing Exploitation of Natural Resources
Batteries require several critical materials, which are non-renewable and extracted in vast mining operations that cause damage to the environment. Essential natural resources used in battery production include lithium, nickel, copper, cobalt, and manganese.
Compared to fossil fuel technologies, technologies such as batteries, which are low-carbon solutions to current ecological challenges, require more metals per unit of energy. Electric vehicles currently dominate the market, and the rapid growth in the EV sector is consequently increasing the number of batteries manufactured globally.
As demand for batteries, other green energy storage devices, and renewable power generation technologies increases, the exploitation of essential natural resources is increasing. Waste volumes from mining operations are predicted to increase exponentially in the coming decades, presenting challenges for the mining sector.
One main issue with the increasing exploitation of natural resources for batteries and other technologies is an exponential growth in annual mining waste. Mining also increases land disturbance and environmental pollution.
The Scale of Mining Waste
Mine waste, such as tailings, can contaminate groundwater if not safely stored and monitored. This can cause marine plants and animals to die off, threaten clean and sanitary water supplies for vulnerable populations, and cause serious health problems in individuals.
According to current estimates, every year, billions of tons of mining waste are generated globally. While not limited to the extraction of transition metals and other elements for use in batteries, the growing demand for battery and energy storage technologies plays a part in the acceleration of mine waste.
Historically, it is estimated that 92.5 billion tons of copper tailings have been produced. If it is assumed that 40% of global tailings production is due to copper mining, this figure could reach 200 billion tons.
Approximately 101,583 km2 of land has been disturbed worldwide by the mining industry, with waste storage facilities and disposal sites responsible for around 50% of the total land area. Approximately 44.5 billion cubic tons of tailings are currently stored, with 12 billion tons produced yearly.
Mining-Centric Strategies for Reducing Waste
To mitigate the vast environmental impact of the mining sector, such as waste material production, storage challenges, and contamination of groundwater sources and land, mining companies must implement mining-centric strategies.
With decarbonization placing new demands on the mining industry and waste management, new and radical approaches to waste management are needed. Challenges associated with waste toxicity, management, and potentially catastrophic infrastructure failures must be comprehensively addressed.
Predicting future waste tailings and rock generation relies on global models of future demand and variables that affect extractive processes' efficiency. Several variables need to be accounted for by mine planners and professionals working in areas dealing with mine remediation strategies.
The accurate prediction will aid in developing processes and regulations that mitigate future social, economic, and environmental impacts and risks to communities living near mining operations.
Proper waste reduction strategies will provide beneficial outcomes such as lower toxicity and contamination risk, reduced risk of mine tailings dams catastrophically failing, and smaller volumes of waste and environmental footprints.
Which Future Mining Waste Strategies Could be Promising?
A recent paper published in Resources, Conservation and Recycling has explored six possible strategies to reduce mine waste. These are mine waste reprocessing, in-situ recovery, ore-sand co-production, dry-stacking and co-mingling, environmental desulfurization, and preconcentration and coarse particle flotation.
Individually, these processes may not be able to provide efficient waste removal. However, they provide viable alternative methods for mitigating the predicted increase in waste materials from decarbonization technologies if employed in conjunction. The paper notes that method choice is site-dependent.
While several critical technical and economic challenges exist, which will govern mine waste disposal in the future, intense research is currently being undertaken into this key issue in the mining industry. As the industry rapidly decarbonizes, alternative strategies to current, highly wasteful practices will be needed.
References and Further Reading
Valenta, R.K. et al. (2023) Decarbonisation to drive dramatic increase in mining waste–Options for reduction. Resources, Conservation and Recycling Vol. 190 [online] sciencedirect.com. Available at: https://doi.org/10.1016/j.resconrec.2022.106859
Gramling, C (2023) Rare earth mining may be key to our renewable energy future. But at what cost? [online] sciencenews.org. Available at: https://www.sciencenews.org/article/rare-earth-mining-renewable-energy-future
Nayar, J. (2021) Not So “Green” Technology: The Complicated Legacy of Rare Earth Mining [online] hir.harvard.edu. Available at: https://hir.harvard.edu/not-so-green-technology-the-complicated-legacy-of-rare-earth-mining/