Science

Address: Steel's green future

Scientia Professor Veena Sahajwalla
Wednesday, 8 May, 2013

Scientia Professor Veena Sahajwalla has become the first Australian to deliver the global iron and steel industry's most prestigious lecture.

Professor Sahajwalla told the meeting in Pittsburgh, in the US, that steelmakers have a largely untapped opportunity to make a meaningful contribution to solving the world’s growing waste problem while cutting their own production costs.

Delivering the Howe Memorial Lecture, she released research demonstrating that many problematic waste materials can be cleanly and safely absorbed into steel making.

Working with Arrium Ltd (formerly OneSteel), Professor Sahajwalla’s earlier research into high temperature reactions in electric arc furnace steel making led to the invention and commercialisation of a steel making process utilising waste. OneSteel’s plants in Sydney and Melbourne have transformed 1.6 million waste tyres into new steel to date, after testing proved that coke mixed with polymers such as rubber sourced from waste tyres performs better than metallurgical coke alone in electric arc furnaces. The process not only reduces the cost of raw materials but has enhances furnace efficiency, cutting power usage.

In addition to waste tyres – a significant environmental threat worldwide, steel makers can potentially absorb a wide range of other wastes – including large-scale agricultural residue and various plastics, according to new UNSW research described in the Howe Memorial Lecture.

“That opportunity lies in the high temperatures of steel making furnaces. I am not suggesting we burn waste for energy. What I am proposing is that we leverage high temperatures to literally re-form waste materials into resources,” Professor Sahajwalla says.

“In doing so, steelmakers can play a leading role in globally significant, large scale recycling, without making fundamental changes to the way we manufacture steel – by re-purposing major waste streams as raw materials, simultaneously reducing production costs and enhancing the sector’s environmental credentials.”

She says the impetus for steel makers to innovate has never been greater due to the rising costs of raw materials, global pressures for competitive pricing and environmental considerations. Meanwhile, waste stockpile are accumulating at an accelerating rate.

“These are clearly incompatible trends which, if we persist with business as usual, will only increase tensions for the industry –making a clear case for change.”

Professor Sahajwalla's full speech and an excerpt are available on request.

Media contact: Steve Offner, UNSW Media Office:  s.offner@unsw.edu.au  0424 580 208/ +61 424 580 208