Challenging the conventional – Dry tailings can be efficient
In the early stages of the mining industry, tailings were disposed in the most convenient manner, such as in downstream running water or down drains. Because of concerns about these sediments in water and other issues, tailing ponds came into use. However, considering the recent tailing dam failures and growing need to use water more responsibly, and the prerequisite for the mines to keep their costs in control, a completely new and forward-looking approach is needed for tailings management.
The way tailings are handled can have a long-term impact on the mines’ economic efficiency as well as on the ecology. Metso believes dry stacking of tailings as the most promising and sustainable way forward.
High capital expenditures (CAPEX) and operating expenses (OPEX) are the two key elements of profitability which have been a barrier for mining companies to invest in dewatering solutions. At Metso we are challenging the conventional thinking, while changing the industry view around the costs associated with dry tailings and stacking. Contrary to the conventional belief, dry tailings can be more efficient from a CAPEX and OPEX perspective when compared with wet or paste tailings.
Ensuring economic viability of tailings handling
The technology is evolving and shifting the gears towards adoption of smart and hybrid solutions that maximize ore and water recovery while optimizing operational costs. At the same time, the mine operators need an economically viable solution to dewater high tonnage of tailings when compared to traditional technologies.
To address these industry needs, Metso Tailings Management Solutions takes a comprehensive approach and combines three practices - dewatering the tailings, handling them properly and reprocessing new and existing ones.
- Tailings dewatering – The high capacity VPX™ from Metso enables up to 90% water recovery in tailings, with a cake moisture content below 7%. IPS thickeners use less of flocculants, or chemicals thus reducing OPEX substantially. Also, 50% smaller plant footprint is a huge benefit when considering the cost of land and civil works.
- Handling – Wide ranging solutions such as conveying, pumping, stacking and reclaiming result in efficient and cost-effective transportation and storage of dewatered tailings for large mining operations.
- Reprocessing - Extracting valuable minerals from legacy dams will not only help to generate additional revenue but also enable cleaning up tailing dams in suitable way by dewatering. Our analysis shows that reprocessing is very attractive from a cost perspective in comparison with virgin material – we simply turn waste into value.
Making the right choice - towards value creation
Tailings management is not a matter of finding the most technically suitable equipment or solution; it is about transformation and taking the minerals processing strategy to a new level. At Metso, we bring a step change in dewatering technology to accommodate huge volumes of tailings, while ensuring efficient and economical operations. We strongly believe that within a few years, dry tailings will be the new established standard in the mining industry.
A conventional view is still dominating the discussion around smarter and efficient management of mine tailings. As futuristic organizations, we should embrace competitive and viable solutions that not only enhance productivity but creates a positive difference to the environment and natural resources. It is time to replace the old and negative risk-avoidance position with a new value creation model.