Researchers in Sudbury, Ontario, are focusing on expanding bacteria-powered technology to extract valuable metals from old mine waste on a larger scale. MIRARCO Mining Innovation is running a pilot facility to test how microbes can break down mine tailings, the leftover material from mining operations, and release essential minerals like nickel, cobalt, and copper through bioleaching.
The bioleaching technique, commonly used in international mining with around 30 operational sites globally, has not yet been fully implemented on a commercial scale in Canada, as per Nadia Mykytczuk, the CEO of MIRARCO. During a recent tour of the 10,000-square-foot pilot facility in Sudbury, Mykytczuk highlighted the immense potential of the local mine tailings, estimating them to contain billions of dollars worth of nickel.
Although the value of the waste material is significant, companies have been hesitant to invest in reprocessing the tailings due to the high costs associated with transporting the material back to the smelter. Consequently, the traditional approach involves mixing tailings with water and storing them in vast ponds, raising concerns about potential long-term environmental risks.
Jaime Kneen, from MiningWatch Canada, emphasized the environmental risks associated with tailings storage, including the potential for acid generation and metal leakage into the surroundings. He pointed out the dangers of relying on dams to contain the wet material, citing the Mount Polley mine tailing dam collapse in British Columbia in 2014 as a cautionary example.
Both federal and provincial governments have been urging for increased critical mineral development to secure the supply chain for clean energy technologies and national defense. Mykytczuk emphasized that bioleaching not only addresses the demand for critical minerals but also aids in mine cleanup efforts, presenting a significant opportunity to extract valuable minerals from mine waste quickly.
The bioleaching process involves grinding down tailings and combining them with a liquid solution to feed the bacteria responsible for breaking down the minerals. As the bacteria interact with the minerals, metals are released into the liquid. The extracted metal is then processed through a series of reactors to obtain it in liquid form.
The team at the Sudbury facility is also exploring methods to convert the extracted metals into industrial-grade products. The next phase involves transitioning from pilot testing to full-scale operations within the next few years, aiming to establish Canada’s first commercial bioleaching operation.