Rio Tinto Developing Process to Use Biomass for Making Steel

By Rhiannon Hoyle

Rio Tinto PLC said it is developing a way for biomass to replace coking coal in steelmaking as the mining giant seeks to safeguard demand for iron ore, its most lucrative business.

The world's second largest mining company by market value is testing a process at a small-scale pilot plant in Germany, which uses raw biomass with microwave technology to convert iron ore to metallic iron without the need for coal.

"We are encouraged by early testing results of this new process, which could provide a cost-efficient way to produce low-carbon steel from our Pilbara iron ore," said Rio Tinto's iron ore chief executive, Simon Trott. The Anglo-Australian miner said it has a patent pending on the process.

Rio Tinto, which stopped mining coal in 2018, is the world's top producer of iron ore alongside Brazil's Vale SA.

The company doesn't make steel, however Rio Tinto and other top miners have become increasingly concerned about the outlook for commodities used in energy-intensive industries such as steel as a global push to cut carbon emissions gathers pace. More than 70% of Rio Tinto's so-called Scope 3 emissions--greenhouse gases related to its products but outside the company's direct operational control--are generated when its iron-ore customers turn the commodity into steel.

Rio Tinto said the biomass project is one of a number of avenues it is pursuing in a bid to reduce steel-industry emissions.

The company earlier this year set targets for lowering Scope 3 emissions that included a goal to invest in technologies that could cut the carbon intensity of producing steel by at least 30% from 2030.

Rio Tinto said it will need to work out how to source enough sustainable biomass to run the process on a commercial scale. Critics say the use of biomass can cause deforestation and affect food supply.

The process it is trialing in Germany uses plant matter known as lignocellulosic biomass, which would include wheat straw, corn stover and purpose-grown crops. The company said it cannot use foods such as sugar or corn and would not use biomass sources that support logging of old-growth 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," said Mr. Trott.

Write to Rhiannon Hoyle at [e-mail]

(END) Dow Jones Newswires

October 13, 2021 09:14 ET (13:14 GMT)

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