In the run-up to UNESCO’s World Engineering Day for Sustainable Development (March 4), to create features a series of talks with experts, revealing the evidence – including major innovations and projects, challenges and solutions, opportunities and risks – that prove Australian engineers are leading the way to a better future. find all to create WED22 content here.

The technical challenge in producing green steel has been supplying hydrogen to an electric arc furnace so that steelmakers can continue to produce efficiently.

“The challenge for us has always been how to enable a steelmaker to use hydrogen in the process,” said Veena Sahajwalla HonFIEAust, Honorary Member of Engineers Australia, Founder of the Center for Sustainable Materials Research and Technology ( SMaRT) at the University of New South Wales.

“Our polymer injection technology uses rubber tires, a rich source of hydrogen, in the ovens. It balances different chemical reactions to make hydrogen work for us, releasing hydrogen from tires and enabling efficient steel production.

It’s a win-win approach. Hydrogen does not need to be produced outside of the process, a previously problematic waste becomes a valuable resource and the environment benefits.

Currently, polymer injection technology allows a partial replacement of coking coal in electric arc furnaces. This was the objective of the first phase of the project.

Sahajwalla, his team and their business partner, Molycop, have now been funded to find ways to introduce more tire rubber into the process.

“We will also work with Molycop to bring green steel technology to the world,” she said.

And it’s not just about using tire rubber as fuel anymore. Sahajwalla’s work now aims to use coffee waste for the same purpose.

Another new challenge is to transfer green steel technology from the electric arc furnace environment to the blast furnace environment. It’s all very well to make green steel from scrap materials, Sahajwalla said, but how, for example, can a company like BlueScope integrate the process into its existing infrastructure?

“The answer, of course, is that we have to find out,” she said. “Thanks to our recent funding, some of these companies are likely to start their own journey towards green steel.

“We don’t expect companies to invest in new assets, but rather to take our intellectual property and start customizing the solution for their own purposes.”