Achieving a circular economy will require much more efficient mining and processing, much more recycling of metals, much more reprocessing and recycling of mine waste, particularly tailings dumps and dams.

This was highlighted by Finnish Geological Survey organisation GTK Circular Economy Solutions Unit head Jouko Nieminen in an interview with Engineering News & Mining Weekly at a fringe event of the Investing in African Mining Indaba 2023, in Cape Town, last month.

But mining would still be needed. Lots of mining, in fact.

“In order to have a truly circular economy world, we will need more mining, to get more metals into that economy,” he pointed out. “We’re going to have to have tens, even hundreds, of new mines worldwide. There is a clear and very large need for increased activity in exploration and in the opening of new mines, to support the circular economy.”

But a new approach was needed to mining and minerals processing. Currently, in many mining operations, 98% of the material extracted was ‘waste’ and only 2% was ‘valuable’. Miners would have to consider how to extract everything valuable from their ore, and not just their target metal. This, he noted, was already being done in certain places, but whether or not mines did this was determined by economics.

“We need to develop zero-waste mining processes,” he affirmed. Ideally, all waste should be recycled, leaving no tailings. But that would not be easy, in practice. As much waste as possible should be recycled, remaining waste should be separated into its different factions and stored separately, while extracted rocky material should be put back into the mine tunnels, when mining had concluded. A lot of work still has to be done on this.”

Of course, existing wastes had to be recycled. Tailings had to be reprocessed to retrieve metals. “This is not the whole solution, but it is part of the solution.”