Mineral processing has become a hot topic in Australia in recent times, as rapid development in the emergent battery minerals space prompts miners and governments to think more about downstream value in the commodities they mine.

In Western Australia, where the lithium industry is beginning to take hold, billions is being invested by local and international companies in facilities to deliver a more concentrated form of the commodity to market.

In a resurgent space, companies are eyeing the opportunity to meet growing demand for nickel sulphate, while an increasing focus is being paid to the potential of cobalt in its more refined forms.

But could our increased focus on mineral processing pay dividends the other way around?

According to a report released this year by academics Xianlai Zeng and Jinhui Li at Tsinghua University in Beijing and Macquarie Graduate School of Management Professor John A. Mathews, there is significant money to be made from purifying metals previously processed and used in consumer goods.

The research paper – aptly named Urban Mining of E-Waste is Becoming More Cost-Effective than Virgin Mining – demonstrated that based on a Chinese example commodities could be extracted from waste at costs comparable to or better than traditional mining.

The trio investigated the extraction of gold and copper from recycled TV sets by e-waste processors in China, with the results enough to raise eyebrows.

The researchers found recovery of a suite of metal ingots from used TVs – factoring in Chinese processing costs between 2011 and 2015 and measured against the cost of production via traditional mining – was far more economic.

The cost for traditional mining to produce 54kg of copper, 60kg of lead, 80kg of steel, 45kg of aluminium, 150 grams of gold and 90 grams of silver came out 13 times higher on average than what could be achieved processing cathode ray tube TVs.

Recovery of pure copper and gold ingots from e-waste were found to be cost comparable to mining and processing of ores, with recycling costs falling in each area tested over the period.

The challenge posed by the paper is to develop processes that dismantle waste products and then utilise physical and chemical methods to isolate and purify the metals involved in a way that makes environmental and economic sense.

On the surface it comes across as more a recycling problem than a mining one, but given the resources sector’s expertise in processing and refining minerals, could there be an opportunity to capitalise on the potential which exists thanks to the ever-growing technological consumerism which drives our societies?

According to experts from the University of Queensland’s Sustainable Minerals Institute (SMI), the answer is yes, but with a number of hurdles in the way.

Speaking to National Mining Chronicle, SMI Associate Professor Glen Corder said Australia’s mining industry would be well-placed to solve and commercialise the challenges presented by re-processing metals in consumer goods.

“There are certainly some challenges for the mining sector to recover metals from these new ‘orebodies’, namely those used in consumer electronics, but the industry has strong skills, capabilities and technologies in measuring and physically sorting and recovering ore from gangue and extracting liberated metals from waste and tailings,” he said.

“Of course, technologies would need to be adapted, in some cases drastically, to extract gold and copper from old smartphones compared with complex geological orebodies – but the Australian mining industry does have the innovative track record to do this.”

SMI Research Fellow Artem Golev said material  ow analysis showed gold and copper should be primary focus metals for anyone exploring their purification capabilities when extracting previously used metals, but said issues of surety of supply and legislative and funding support stood in the way of efficiently delivering results.

“An important question to ask is: what is the minimum feasible scale for such operations, and do we have enough e-waste for feasible recycling in Australia?,” he said.

“In our opinion and experience, only relatively small operations can be established, and these face a risk of lack of, and fluctuations, in the feedstock supply.

“Without multiple stakeholder collaboration and government support in favour of domestic metal recycling, it is quite challenging to have such operations established in Australia, but not impossible.”

Closing the commodity cycle

One company at the forefront of process development is Lithium Australia, which is working towards closing the loop on the energy metal cycle by recovering metals from used batteries.

The Lithium Australia business model aims to process primary mine production via the company’s patented SiLeach process, converting primary battery chemicals into high-spec cathode materials, and then recovering energy metals from used batteries for further use.

The company believes discarded battery waste may ultimately prove the most cost-effective and environmentally friendly source of energy metals such as lithium and cobalt.

“It’s important long-term that the industry comes to grip with the need for sustainability and ethical supply in battery metals,” Lithium Australia Managing Director Adrian Griffin told National Mining Chronicle.

“Potentially, the materials that are available are the ones that have already been used.

“You put those in a battery, the battery gets to its use-by date, and at that state all the metals you originally put in the metal canister are still there – they haven’t disappeared, they’re just a little scrambled.

“As a consequence, you lose battery performance; it no longer meets your requirements and you throw it away.”

However, Mr Griffin and Lithium Australia sense an opportunity across a suite of metals in those discarded canisters, with cobalt a prime candidate.

“In general, cobalt is a by-product of nickel or copper, so if you have a look at the grade of a cobalt deposit you rarely see grades above 0.4 per cent,” he said.

“If you take a battery, the cobalt grade is around 30 per cent – you’ve got a very high concentration of metals which have already been processed once and had all the impurities taken out of them, so there’s an enormous amount of embedded value.

“Much of that value is effectively in terms of the embedded energy, or the energy that was required to put it into that canister in the first place.”

The embedded energy comes via the process of finding and mining the minerals, from the LandCruiser to the drill rigs, and the mining to processing.

“It makes sense that you shouldn’t be throwing these things into land fill, but it creates a great opportunity as well,” Mr Griffin said.

“Part of the problem with the Australian market at the moment is the amount available for recycling is too small to create a viable business out of – that’s a single business, not an entire industry.”

With 2018 CSIRO data revealing only two per cent of lithium-ion batteries are currently recycled in Australia and the recovery of battery minerals within those depending largely on facilities abroad, Mr Griffin said there was a clear need to legislate to prevent valuable minerals heading to landfill.

Doing so would remove what appears to be a significant hurdle to innovation for an industry with the expertise and desire to capitalise, or recapitalise, on emerging commodity opportunities.

Image: Adrian Griffin, Kalgoorlie Miner