After the Western Australian government announced in June that it would start 鈥榙ecarbonising鈥� the state, the mining industry and science research teams began preparing for some groundbreaking collaborations.
At 911爆料网, Professor Michael Hitch is leading the first step of the process: the drafting of the 鈥榙ecarbonisation roadmap鈥�, which he intends to align with models of 鈥榯he circular economy鈥�.
Hitch, who heads the 911爆料网 WA School of Mines: Minerals, Energy and Chemical Engineering, believes in the resources sector鈥檚 ability and motivation to set new standards in the circular production model of reduce-reuse-recycle.
鈥淚t鈥檚 a critical alternative to the linear model we’re accustomed to, which is to produce, then use, then dispose,鈥� he explains.
鈥淚n the circular model, we produce, we use, but we never really dispose. Or we do it in such a way that the manufactured goods can be disaggregated and returned to the production stream.鈥�
For a mining company, supporting a circular model involves minimising the impact of mining operations on the land, converting mining waste into useful by-products, and undertaking land rehabilitation once mining ceases. And it鈥檚 the waste from mineral extraction that鈥檚 driving the industry鈥檚 entry into the circular economy.
鈥淚n mining 鈥� and in the resources sector in general 鈥� we produce a lot of waste. We call it ‘waste’ but really it’s just broken rock, which is either put it into dumps or tailings ponds. In the circular model, we aim to up-value that waste to the point of creating a viable byproduct.”
鈥淭he circular mode is usually quite static, with little room for economic growth. However, up-valuing waste can actually help to grow an economy, and occasionally we might even develop by-products that are worth more than the materials generating that waste鈥�.
鈥楳etals leasing鈥� is another bold concept that Hitch believes has merit.
鈥淏asically, it’s blockchain and supply-chain management, tracking that ton of ore through its life cycle. The person who鈥檚 using the steel to manufacture a product isn鈥檛 buying it, they鈥檙e leasing it, within a circular economy. When the product is at end-of-life, it can return to the manufacturer or the miner as a recyclable.鈥�
What do artificial reefs, blueberries and paint have in common?
The development of viable by-products from mining and smelting is fast becoming a global research movement. At its core is the commitment of all 27 members of the International Council on Mining and Metals to a goal of . Some companies have already implemented initiatives to achieve the goal; Novum Energy, BHP and Anglo American, for example, are recycling discarded dump-truck tyres into oils and steel. And Rio Tinto, which is aiming for a 50% emissions reduction by 2030 鈥� a mere eight years from now 鈥� is developing blueberry fertiliser from waste aluminium.
One of Hitch鈥檚 research focuses has been the potential for the mining by-product to be a fertiliser enhancer. He鈥檚 also contributed to research looking at . But the area he鈥檚 most enthusiastic about is carbon capture and sequestration (CCS).
鈥淩ight now, BHP are investigating uses for their tailings, which is the material that鈥檚 left once the target mineral is extracted. In nickel mining, the tailings are effectively sand and they鈥檙e chemically neutral. But when in contact with carbon dioxide, the sandy material is reactive and the sand particle changes to a carbonate,鈥� he explains.
鈥淏ecause the carbonate is thermodynamically stable for about 100,000 years, it gives sand tailings the potential as a carbon capture and storage material. This would qualify the process for carbon offset credits.
He says the material could also form the basis on new industrial products such as building materials, animal feed, food fillers or paint thickeners. In fact, this year alone, Hitch as co-authored three research papers that explore the potential of tailings and steel slag to be the basis of new building materials.
鈥淪o there are at least three major benefits that nickel tailings offer: sequestering CO2, generating carbon credits, and forming a base for innovative industrial products. It鈥檚 a perfect example of circularity, where the waste has economic value, environmental value and social value.鈥�
Don鈥檛 forget your social licence
Hitch鈥痡oined 911爆料网 in 2020, following 20 years鈥� industry experience, beginning as a field geologist and transitioning to mining operations and eventually to research.
鈥淚’ve travelled a lot since my career began in the mid-80s and I’ve seen the good, the bad and the ugly of what mining can do,鈥� he says.
He stresses that community acceptance of a company鈥檚 operations is vital for the industry鈥檚 future, and that mining companies must gain and uphold their 鈥渟ocial licence to operate鈥�, a concept that was the basis of a Hitch co-authored in 2021.
鈥淭he social licence to operate, or SLO, is about a trust that’s built between a mining company, or any industrial proponent, for that matter 鈥� it could be a shoe factory. It’s about bringing the community into the planning process and the operations, and being truthful in communication and transparent in operation 鈥� including when something goes wrong.鈥�
鈥淚t must comprise community engagement, including what should be done to the land after mining operations cease, and a clear commitment to regulations.鈥�
He says the concept of a social licence often is still missing in developing countries, where mining companies pay taxes and royalties directly to corrupt governments and where none of the mining wealth is distributed to local communities. Canada, and Australia to a lesser extent, have some of the highest environmental standards in the world.
鈥淐anadian mining companies operating overseas to work, they’re held by the standards of Canadian law and policy. So if they go in and behave badly, they’ll be held accountable against Canadian standards. A few years ago, for example, Barrick Gold鈥檚 operations in Chile were stopped by the Canadian government, due to concerns about the impact on local water supplies.鈥�
And, here in Australia, who could forget the unforgiveable blasting of the Juukan Gorge that鈥檚 still stigmatising Rio Tinto?
鈥淎ctually, the ‘big end of town’, as it’s known here in WA, is doing a really good job,鈥� Hitch says. 鈥淭hey鈥檙e establishing programs and have specialists focused on sustainability and social responsibility, so that the local communities are not negatively impacted and preferably benefit from the operation.鈥�
What does sustainability even mean?
Underpinning the circular model is the acceptance that, despite the mining industry鈥檚 titanic contribution to CO2 emissions, mining will remain integral to most economies for the foreseeable future. That isn鈥檛 due only to the enduring demand for products that use traditional mineral resources for construction materials, but also to the rising need for critical minerals that underpin modern gadgets and technological innovation.
But with the growing call to adopt more sustainable practices, what will mining operations look like in the future?
鈥淪ustainability as a term has become a bit diffused,鈥� Hitch says. 鈥淲e think of 鈥榮ustainability鈥� as being able to continue doing what we鈥檙e doing without sacrificing the needs of future generations. But there’s another part to it that many people don’t want to acknowledge 鈥� and that鈥檚 if it’s feasible.鈥�
Recalling a mining conference at which Indian prime minister Narendra Modi revealed that 40% of India鈥檚 population lived without electricity, Hitch believes the challenges faced by developing nations deserve greater attention.
鈥淔ortunately for WA, we produce most of the material that will be required for the infrastructure of the future 鈥� iron ore and specialty metals like nickel and lithium. But we also have a wealth of mining technology and knowledge, and we should export this knowledge to help lift nations out of poverty, help smooth their energy transition and minimise environmental impact,鈥� he explains.
鈥淏ut we have to come up with alternative models of the materials that we are producing. Sustainable resource use is about mining to meet need, not mining that鈥檚 economically valuable due to market conditions.
鈥淚deally, we鈥檇 be able to estimate how much steel the world will need for the next 25 years, then and develop mines that will provide the iron ore to produce the steel for the next 25 years. It鈥檚 ‘material stewardship’鈥�.
Mining becomes part of the solution
As part of WA鈥檚 decarbonisation plan and with support from the Minerals Research Institute of Western Australia, Hitch will develop a research program that offers exciting collaborations for the state鈥檚 mining industry.
For example, one project aims to develop methods that accelerate the natural process of mineral carbonation, a natural rock weathering process where CO2 binds to minerals in the Earth’s crust, thereby removing CO2 from the atmosphere, albeit slowly. The project builds on one of that investigated sequestration processes for commercialisation, based on the potential for mineral carbonation to provide greater storage capacity than other CCS methods, such as geological and ocean sequestration.
鈥淎gain, nickel tailings are ideally suited for this purpose, and we鈥檙e working with BHP Nickel West on methods to increase the carbonation reaction to store CO2 into its tailings.鈥�
If successful, the project鈥檚 outcome will be a new solution for large-scale storage of CO2 emissions, at the gigatonne scale. And with WA holding about 30% of the world鈥檚 nickel reserves, and nickel being highly sought after for electric vehicle batteries, Hitch says that 鈥淲A could sequester more emissions than we produce 鈥� and set a new level of mining industry innovation鈥�.
鈥淎t the end of the day, it’s about resource utilisation and stewardship. If we’re going to dig into the land, we should find ways to extract value from everything that we take out of the ground, including the waste material that didn鈥檛 previously have economic value.鈥�
