Rio Tinto is considering the use of sustainable technology in its steelmaking process, joining the likes of Fortescue and BHP in tackling the iron ore sector’s emissions challenge.
This morning, Rio announced it had developed a new steelmaking method that uses ‘sustainable biomass’ instead of coking coal, which is mixed with iron ore in blast furnace operations.
Rio said the biomass, comprised of plant matter known as lignocellulosic biomass, would be blended with iron ore from its Pilbara mines and heated with ‘microwave technology’ that could be powered by renewable energy.
The patent-pending process could be a cost-effective option to reduce emissions, Rio said.
Further testing is underway, with the London-based miner’s research team also working with an engineering group at the University of Nottingham in developing the technology.
Chief executive of the company’s iron ore operations, Simon Trott, said early test results of the process were encouraging.
“More than 70 per cent of Rio Tinto’s scope 3 emissions are generated as customers process our iron ore into steel, which is critical for urbanisation and infrastructure development as the world’s economies decarbonise,” Mr Trott said.
“So, while it’s still early days and there is a lot more research and other work to do, we are keen to explore further development of this technology.
“If this and larger-scale tests are successful, there is the potential over time for this technology to be scaled commercially to process Rio Tinto’s iron ore fines.”
The University of Nottingham’s head of chemical and environmental engineering, Chris Dodds, agreed the technology could have a global impact in decarbonising the steelmaking process.
The use of raw biomass, Rio said, could also avoid the inefficiencies and associated costs of similar technologies which first convert the biomass into charcoal or biogas.
Lignocellulosic biomass includes agriculture by-products – such as wheat straw, corn stover and barley straw – and purpose-grown crops.
Rio noted it would not use biomass sourced from forests.
“We know there are complex issues related to biomass sourcing and use and there is a lot more work to do for this to be a genuinely sustainable solution for steelmaking,” Mr Trott added.
“We will continue working with others to understand more about these concerns and the availability of sustainable biomass.”
Last month, Fortescue announced it would target net zero emissions – including from upstream and downstream activities not controlled by the organisation – by 2040, with crude steel manufacturing accounting for 98 per cent of its scope 3 emissions.
More recently, the Andrew Forrest-chaired company inked deals with the NSW and Queensland governments through its green hydrogen arm, Fortescue Future Industries, which is also part of the iron ore major’s plans to produce ‘green steel’.
Fellow miner BHP has also outlined scope 3 targets but has not settled on a date to achieve net zero emissions.
The company earlier this year said it would support the iron ore sector in developing technologies and pathways capable of achieving a 30 per cent emissions reduction in steelmaking by 2030.
In that time, BHP also hopes to cut emissions from chartered shipping of its products by 40 per cent.