Rio Tinto: steel firms need ‘every technology in the book’ to go green

Mining giant is investing US$143m in new facility to test microwave- based process

MINING company Rio Tinto says the steel industry will need “every technology in the book” to decarbonise, after announcing its plan to develop a R&D facility for its low-carbon ironmaking process in Western Australia.

The BioIron Research and Development Facility will be built in the Rockingham Strategic Industrial Area south of Perth, near the Pilbara region, one of the largest iron ore provinces in the world.

Instead of coal-based blast furnace processing, Rio Tinto’s BioIron process uses raw biomass and microwave energy to convert Pilbara iron ore to metallic iron.

Michael Buckley, Rio Tinto’s steel decarbonisation and BioIron technical manager, said: “We need to come up with new technologies that don’t rely on coal if we’re going to transition.”

He added: “Considering the challenge of decarbonising the steel industry, which produces 8% of global emissions, we’re going to need every technology in the book to decarbonise this sector. We’re going to need hydrogen. We’re going to need biomass. We may even need electrolysis-based processes.”

The sustainability of biomass

In 2021, Rio Tinto partnered with the University of Nottingham in the UK and Finnish technologies firm Metso to run a pilot-scale facility testing BioIron.

Engineering consulting firm Hatch independently reviewed the results and noted that BioIron had “the capacity to reduce greenhouse gas emissions”.

The facility in Western Australia will be ten times larger than its predecessor and operate with a 1 MW magnetron, necessitating vastly more biomass to run the process.

Rio Tinto has been working with civil society organisations in Australia to sustainably source biomass from agricultural land in Western Australia, namely from wheat, barley, and soil grown in the region.

Buckley said: “We want to be able to test a wide range of biomass types, so there’ll be facilities to test other types of biomass there, but as a fundamental base load, we’ll be looking to source it from the agricultural byproducts locally.”

He added: “Based on our numbers, we think we would use only about a third of the electricity of a green hydrogen-based process. A lot of the energy is coming from the biomass, so we don’t need a large amount of electricity.”