The CSIRO has demonstrated that agricultural waste can be used to partially replace coal in steelmaking, marking a potential shift in how the carbon-intensive sector operates.
The project, conducted in partnership with the Indian Institute of Science and industry collaborators, validated the use of rice husk pellets to produce biomass-derived synthesis gas (syngas) for iron ore reduction at a commercial steel plant in India.
The trial confirmed that blending agricultural waste at rates of five to 10 per cent into existing gasifiers could maintain stable production without compromising performance.
“This trial is a world-first demonstration of how agricultural waste can be harnessed to decarbonise steelmaking at scale,” CSIRO senior experimental scientist Warren Flentje said.
“By blending rice husk pellets into commercial gasifiers, we’ve shown that biomass can replace coal without compromising performance. This is a major step forward for sustainable steel production in India and globally.”
Steelmaking accounts for around one-tenth of global carbon emissions, with the sector heavily reliant on coal-based processes.
The challenge is particularly acute in India, where the industry is expanding rapidly and emits approximately 2.55 tonnes of CO₂ per tonne of steel, well above the global average.
The trial was undertaken at a large-scale steelworks in Odisha, in collaboration with technology provider RESCONS Solutions, and supported by the Australia–India Green Steel Research Partnership.
According to the CSIRO, the results indicate the approach is viable at commercial scale and could be integrated into existing direct reduced iron (DRI) processes, which are widely used across India.
CSIRO research group leader for green metals production Keith Vining said the work highlights how regional resources can support lower-emissions industrial processes.
“India’s steel sector is both a major employer and a significant source of emissions,” Vining said.
“Our partnership with the Indian Institute of Science and JSPL has demonstrated that biomass can be a viable alternative to coal, especially in regional areas where surplus agri-waste and coal DRI facilities co-exist. The next phase will focus on increasing biomass replacement rates and assessing impacts on the direct reduction process.”
Beyond emissions reduction, the approach also presents an opportunity to utilise agricultural residues that are often underused or burned, contributing to air pollution.
If deployed across India’s steel sector, CSIRO estimates the technology could reduce emissions by up to 50 per cent, equivalent to approximately 357 million tonnes of CO₂ annually.
RESCONS Solutions managing director professor Govind S. Gupta said developing environmentally sustainable solutions that benefit present and future generation is vital.
“Collaborating with CSIRO and IISc, we are proud to help pioneer the use of biomass in steelmaking, supporting India’s transition to greener industrial practices,” Gupta said.
The research team has also developed a mapping tool to align steelmaking infrastructure with biomass availability, aimed at supporting future deployment decisions.
Further work will focus on expanding the technology to smaller-scale facilities and testing a broader range of biomass feedstocks, as efforts to decarbonise steel production continue.
Jindal Steel executive director Damodar Mittal said the collaboration is a monumental step forward to decarbonisaiton.
“By integrating green energy and biomass into our production processes, we are not only reducing our carbon footprint but also setting a new benchmark for the Indian steel industry,” he said.