A research paper published by Dr Jenine McCutcheon and associate professor Ian Power at the University of Waterloo in Canada has investigated the use of bioleaching to extract valuable metals from dry-stack tailings, while significantly reducing emissions.
Bioleaching is a process where microbes break down ores into their metal components, thus facilitating extraction. According to the research paper, miners can use microbes in tailings to extract metals, particularly ‘dry stack’ tailings from older, less-efficient mining operations, thus reducing pollution risks such as contamination of water sources.
Microbial mineral carbonation is an added benefit because the microbes use CO2 from the air to form a carbon crust that can stabilize the dry-stack.
The process can also be applied to a new mine. “Rethinking how future mine sites are designed in order to integrate this process could result in mines that are carbon neutral from the get-go, rather than thinking about carbon storage as an add-on at the end,” writes McCutcheon.
This process could turn an entire mine into an “industrial carbon sink” that could offset 34% of annual emissions.
Source: Mining Technology
Image Source: BHP Escondida Tailings (via Google Search)