Microbians: the future of copper mining?

A partnership between Chilean copper tycoon Codelco and Japan’s Nippon Metals and Mining is studying a curious alternative to help mining process of the red metal – microbes. The partners set up Biosigma, a biotechnology venture that studies bacteria that break down metals in order to improve copper recovery rates and reduce operating costs.

According to the partners, using bacteria can result in extracting as much as 90% of the total metal at a pit mine, instead of merely 60% recovered in the widely-used methods adopted nowadays. The minerals are placed into acid, and then researchers introduce bacteria that change the solution so that it dismantles the rock and frees copper, in liquid form. After a special electrochemical process, it is then turned into solid metal that can be used in the industrial applications we so much depend on.

The method is cheaper and greener than traditional mining, using microorganisms that naturally live at mining sites and are not pathogenic. The bacteria are also being tested to extract gold and uranium, and a future use may be the cleaning of corrosive acid pollution left over in mining waste.