De Beers pursues carbon neutral mining

A research project undertaken by diamond mining company De Beers Group aims to bring carbon neutral mining to its diamond operations within five years.

The company’s scientists, together with internationally renowned scientists, are investigating the possibility of storing large amounts of carbon at its diamond mines through the mineralisation of kimberlite tailings.

It is the first time extensive research has been done to assess the carbonation potential of kimberlite, a rare type of rock that has ideal properties for storing carbon through mineral carbonation technologies.

Mineral carbonation is a natural or artificial process where rocks at the Earth’s surface react with carbon dioxide and traps it in solid carbonate materials such as kimberlite.

The project aims to accelerate the naturally occurring process of extracting carbon from the atmosphere and storing it at a speed that could offset man-made carbon emissions.

The scientists believe that the carbon storage potential of kimberlite tailings produced by a diamond mine each year could offset nearly 10 times the emissions of a typical mine.

De Beers Group’s project lead, Dr Evelyn Mervine, said that while mineral carbonation technologies are not new, what is new is the application of the technology to kimberlite ore.

“As part of the project, we are looking at how these existing technologies can be modified to develop specific solutions suitable for storing carbon in kimberlite tailings,” she said.

“The research is in its early stages and it may take some time before it is economically or practically achievable to tap into this full storage potential.

“However, even just tapping into a small amount could greatly reduce the net emissions at many of our mine sites in the near future, and possibly lead to carbon-neutral mining at some sites within the next five to ten years.”

She added that as the technology improves, more carbon could be stored in kimberlite tailings, potentially offsetting more emissions than the company is producing.

The research could also applications in the broader mining industry, with the storage characteristics in kimberlite also present in other commodities such as platinum and nickel.