The future of mining: no mine

Mining hasn’t changed in ages. It’s still the same old method of “drill, blast, load, haul, dump, crush, grind, separate, process,” says Professor Scott Dunbar, head of the mining and engineering department at the University of British Columbia.

pond

As the failure of the tailings pond dam at Mount Polley demonstrates, there are serious flaws with business as usual. Ore concentrates are lower, demands higher, and tailings ponds growing ominously. Trouble abounds: dam engineering, environmental disasters, financial loss, and as Premier Clark is quickly learning, a looming political problem.

“These constraints cannot be avoided by innovations within the current paradigm. A radical shift is needed, starting with seeking alternatives to handling and processing large amounts of rock,” warns Dunbar in the Globe and Mail.

One innovation is to use bacteria to dissolve minerals and leave the metal behind. One such bacteria works on toxic gold solutions (gold chloride) and leaves tiny nuggets of gold. No on knows exactly how it works. Maybe the bacteria screens out gold in  an effort to detoxify its environment.

This is not to be confused with other bionic methods currently in use such as bioleaching in which metals are extracted from their ores through the use of sulphur-extracting organisms. While this is better than some traditional methods, the by-products are toxic chemicals such as sulphuric acid.

Refining plants could take a cue from, well, plants. Some plants grow in contaminated soils that contain metals. The metals are soaked up and stored in the plant’s leaves. These so-called hyperaccumulators concentrate metals in soil that would be toxic to related species. Over 500 species of flowering plants have been identified as having this ability to hyperaccumulate metals in their tissues. Future mines could look like farms in which hyperaccumulators are the crop.

Mining natural gas could also be revolutionized through use of microbes. While fracking risks the contamination of water and the demolition of landscapes, micro-organisms can eat coal and turn it into methane: the main ingredient in natural gas.

It’s not futuristic dreaming. The U.S. company Next Fuel has developed technology that demonstrated the production of methane from coal beds. Instead of burning coal, it makes more sense to turn it into a cleaner burning fuel. And deep coal seams that would be inaccessible by conventional mining techniques could be converted to gas producers by coal-loving bacteria.

Not just the conversion of coal to natural gas, but other dirty fossil fuels could be digested by bacteria as well. “Microbial communities also exist in oil sands and in other mineral deposits and their characteristics are just beginning to be understood,” adds Professor Dunbar.

Canada could be a world-leader. We rank first in the world for the production of potash, and in the top five for the production of nickel, cobalt, titanium concentrate, aluminum, magnesium and platinum. Of all the mining companies in the world, 75 per cent are headquartered in Canada.

Canada’s reputation as a global miner has been tarnished by environmental disasters and human rights abuses. While the world will never see us as global boy scouts, innovation could help restore the lustre to our tarnished image.

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1 Comment

  1. Some of these ideas were being discussed in my mining days in the late 1960’s. The scary part was the mining engineers and geologists at that time were proposing the use of nuclear bombs to break up the underground rock enough so the water/bacterial extraction could happen.

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