Industrial mining is expected to continue expanding in the future, with current trends suggesting a two to 10-fold increase in demand for a wide range of commodities by 2060, most notably those required for energy transition technologies.
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‘Ore grades’ refer to the concentrations of the metal or mineral of value, and these have declined by an average of 50 % for many commodities over the past 40 years. This decline has essentially doubled the amount of mine waste (tailings) generated for each unit of valuable material produced.1
Tailings are generally comprised of finely ground rock particles, water, and residual chemicals employed as part of the extraction process.
These residual chemicals can be toxic, often including blasting chemicals such as ammonia and nitrate, and separation chemicals such as petroleum byproducts, caustic agents, and cyanide. They can also include leached metals and other elements, such as copper, cadmium, iron, arsenic, lead, zinc, aluminum, manganese, and sulfate.1
The Importance of Tailings Management
Effective and environmentally friendly tailings management strategies and processes must be in place to handle, store, and remediate these waste byproducts.
This is an increasingly important consideration for current mining operations, with 94 % of organizations set to invest more in tailings management for a wide range of different reasons.1
Environmental Protection
Tailings often contain harmful substances, such as those mentioned above, which can leach into the surrounding ecosystem if not properly contained. This has an adverse effect on flora, fauna, and human health.
Regulatory Compliance
Regulatory bodies and governments have strict standards and guidelines around the collection and management of mining waste.
The Global Industry Standard on Tailings Management (GISTM) stipulates zero harm as the ultimate goal, with non-compliance potentially resulting in considerable legal and financial repercussions. These include mine closures, fines, and loss of operating licenses, depending on geography.
Community Relations
Communities located close to mining operations are often directly affected by the environmental footprint of the mine. Effective tailings management is central to a company’s corporate social responsibility (CSR) commitments and can help mining companies to build and maintain constructive relationships with local stakeholders.
Operational Safety
Tailings storage facilities (TSFs) should be carefully designed, constructed, and monitored to prevent failures that could lead to catastrophic events. These catastrophic failures do occur, with events such as the 2019 Brumadinho dam disaster serving as a major wake-up call for the global mining industry.
The collapse of this tailings dam saw mine waste travel eight kilometers over land, killing 272 people, destroying buildings, and contaminating both the Paraopeba River and the surrounding land.2,3
Investing in advanced tailings management practices and technologies is crucial in mitigating environmental, social, and financial risks, while also aligning with the broader shift towards responsible and sustainable mining operations.
Tailings Management Solutions
Recent years have seen handheld elemental analyzers become increasingly invaluable in mining companies’ tailings management operations. These portable instruments offer several technical advantages, enabling the detailed, real-time analysis of tailings material in the field at various points throughout the mining workflow.
X-ray Fluorescence (XRF) Analyzers
XRF analyzers work by directing X-rays onto a sample, prompting the emission of secondary (fluorescent) X-rays from the elements within the sample. Each element produces a distinct spectral fingerprint, enabling precise identification and quantification.
Elemental Composition Analysis
Handheld XRF analyzers enable the rapid, on-site quantification of tailings’ elemental composition. This capability is essential because the presence of hazardous elements like lead, arsenic, and mercury must be detected and carefully managed to prevent environmental contamination.
Material Characterization
A thorough understanding of the mineralogical content of tailings underpins its appropriate remediation and recycling. For example, identifying valuable residual minerals can improve resource efficiency by informing secondary recovery processes.
Compliance and Monitoring
Handheld XRF devices enable the efficient monitoring of tailings, helping ensure compliance with environmental regulations and adherence to legal standards. This helps prevent potentially expensive fines and sanctions.
Technical and Operational Benefits
There are multiple compelling benefits to integrating handheld XRF analyzers into tailings management, most notably their portability and ease of use. These devices can be transported and operated directly on-site with ease, marking a significant improvement over the more time-consuming traditional methods, which typically require transporting samples to off-site laboratories and extensive sample preparation.
The removal of these cumbersome steps is key to unlocking a more responsive and efficient tailings management process.
XRF technology is also a non-destructive technique, meaning that sample integrity is maintained during analysis. This is especially beneficial for ongoing monitoring programs that may require multiple analyses of the same sample, offering users a more in-depth understanding of the tailings material over time without altering or depleting the sample.
Investing in Tailings Management
The implementation of effective tailings management can result in significant long-term cost savings for mining companies.
Many environmental and CSR benefits are achievable, as well as the possibility of new revenue opportunities via the recovery of valuable minerals that may have been overlooked during initial processing.
The use of handheld XRF analyzers to identify and quantify residual metals within tailings facilitates secondary recovery processes, improving resource efficiency and generating additional income streams from materials that would likely be considered waste otherwise.
Demonstrating a commitment to sustainable practices can enhance a company’s attractiveness to investors and its marketability, with the potential to attract increased investment and business opportunities as the market for environmentally responsible mining operations continues to grow.
References and Further Reading
- Earthworks. (2022) Safety First: Guidelines for responsible mine tailings management, Earthworks, MiningWatch Canada and London Mining Network. (online) Available at: https://earthworks.org/wp-content/uploads/2022/05/Safety-First-Safe-Tailings-Management-V2.0-final.pdf.
- Darlington, S. et al. (2019). A tidal wave of mud: The Brumadinho disaster in Brazil. (online) Available at: https://www.minesandcommunities.org/article.php?a=13923.
- Robertson, P. et al. (2019). Report of the Expert Panel on the Technical Causes of the Failure of Feijão Dam I | Resolution Copper Project and Land Exchange Environmental Impact Statement. (online) Available at: https://www.resolutionmineeis.us/documents/robertson-et-al-2019.
- The Global Tailings Review. Global Industry Standard on Tailings Management – Global Tailings Review. (online) Available at: https://globaltailingsreview.org/global-industry-standard/.
- Sax, S. (2024). Scientists now know how the Brumadinho dam disaster happened, and the lessons to learn. (online) Mongabay Environmental News. Available at: https://news.mongabay.com/2024/02/scientists-now-know-how-the-brumadinho-dam-disaster-happened-and-the-lessons-to-learn/.
Acknowledgments
Produced from materials originally authored by John Margeson from Thermo Scientific.
This information has been sourced, reviewed, and adapted from materials provided by Thermo Fisher Scientific – Production Process & Analytics.
For more information on this source, please visit Thermo Fisher Scientific – Production Process & Analytics.