The mining industry is instrumental for securing the metals necessary for a transition to a more electricity-heavy energy system in the future. It has also been struggling with finding the motivation to invest in these metals. The paradoxical situation has stimulated an alternative approach: recycling and re-mining.
"I genuinely don't see where all of this copper is going to come from at this point in time." The observation was made by Anglo American's chief executive, Duncan Winblad, to Bloomberg three years ago, referring to the projected huge amount of basic metal needed to advance the transition to net zero emissions in accordance with Paris Agreement targets.
But this is not the only thing Winblad told Bloomberg in that 2022 interview. He also said that "There are lots of copper resources in the world, and I think those resources could be brought to book, but the length of time it takes is completely under-appreciated by the market."
Indeed, the long lead times in mining are the biggest obstacle on the net-zero course. The market has developed some appreciation of the fact, but copper prices still don't motivate large-scale greenfield investments. So some miners are turning to alternative approaches to sourcing basic metals.
One of these approaches is re-mining, or recovering metals from tailings. Tailings is a nice name for waste -- more specifically and importantly, mining waste. This waste contains certain amounts of metals that, according to some in the industry, can be recovered and used in the same way that the primary mined metals are used. These amounts of waste metals can be quite considerable and worth recovering.
According to the German research outlet Fraunhofer Institute, there is as much as 100 million tons of copper sitting in tailings dams from copper mining between 1910 and 2010. The current rate of tailings production is a sizable 7 billion tons annually. The metal content in the tailings is tiny, at between 0.1% and 0.5% for older mines and less than 0.1% for modern ones, but some argue that recovering metal content may be worth it to secure the copper that the energy transition needs.
Reuters' Andy Home reported last week that some companies are indeed studying the commercial viability of metal recovery from tailings. These include Hudbay Minerals, which is considering copper recovery from the Flin Flon mine, which closed in 2022 but contains a lot of copper and zinc that is recoverable.
Another company, Australian Cobalt Blue Holdings, is considering a similar project for pyrite tailings as a source of sulfur to be tapped after the closure of a local copper smelter that is currently producing the chemical.
Yet another company, Hindustan Zinc, recently approved an actual investment in metals recovery from tailings for a zinc mine. The investment will be used to build a reprocessing plant with a capacity of 10 million tons per year. The Rampura Agucha is the world's biggest zinc mine.
Re-mining certainly sounds like something that makes sense, especially in the context of a push towards what proponents call a circular economy, with a twin focus on securing necessary materials while keeping waste to a minimum. The problem seems to be technology. To make the extraction of residual metals from tailings economical, the cost of the process must be low enough to ensure its profitability.
The price of copper on international markets is not an incentive right now. It has remained stubbornly low despite projections of soaring demand and shortages. So, while re-mining sounds promising, it may be a while yet before we see tailing dams getting drained and their residual metal contents sucked out and used to manufacture copper wire.