27 Apr. (EUROPE PRESS) –
A new mining technique uses microbes to recover metals and store carbon in the waste produced by this extractive activity.
Adopting this technique of reusing mine waste, called tailings, could transform the mining industry and create a greener, more sustainable future, according to the authors, scientists at the University of Waterloo, who publish results in PLOS ONE.
Tailings are a byproduct of mining. They are the fine-grained waste materials left over after mining the target ore, which are then piled and stored. This method is called dry-stack tailings.
Over time, mining practices have evolved and become more efficient. But the climate crisis and the growing demand for critical minerals require the development of new mineral extraction and processing technologies.
Old tailings contain higher amounts of critical minerals that can be extracted with the help of microbes through a process called bioleaching. The microbes help break down the ore, releasing any valuable metals that were not fully recovered in an environmentally friendly way. which is much faster than natural biogeochemical weathering processes.
“We can take tailings that were produced in the past and recover more resources from those waste materials and by doing so also reduce the risk of residual metals entering local waterways or groundwater,” he said. it’s a statement Dr. Jenine McCutcheon, Assistant Professor in the Department of Earth and Environmental Sciences.
In addition to improving resource recovery, the microbes capture carbon dioxide from the air and store it within mine tailings as new minerals. This process helps offset some of the emissions released while the mine was active and helps stabilize the tailings.
Microbial mineral carbonation could offset more than 30 percent of a mine’s annual greenhouse gas emissions if applied to the entire mine. Furthermore, this microbe-powered technique It gives value to historic mine tailings that would otherwise be considered industrial waste.
“This technique makes better use of current and past mining sites.McCutcheon said. “Rethinking how future mine sites are designed to integrate this process could result in mines that are carbon neutral from the start rather than thinking of carbon storage as an add-on at the end.
“This technology is a potential game changer in the fight against climate change, and the mining industry has a unique opportunity to play a significant role in the future of green energy.“, he assured.
