The world could soon be using old boots and rubber crumbs to make train wheels with a method developed in Australia's industrial heartland.
Steel making is one of the hardest industries to decarbonise because the process depends on high heat, traditionally using coal to fire the furnace.
But Australian steel products manufacturer Molycop and its research partners have commercialised a way of using waste rubber for a cleaner steel-making process.
Molycop produces more than 240,000 tonnes of train wheels, steel bars and other products each year and has been working with top recycling scientist Professor Veena Sahajwalla on her breakthrough technology for green steel.
Prof Sahajwalla, director of Sustainable Materials Research and Technology Centre at the University of NSW in Sydney, initially worked with OneSteel to develop a process to make green alloys by using waste rubber and plastic.
Since then, working with industry partner Molycop for the past decade, millions of tyres have been diverted from landfill.
Molycop said the technology also reduced the steel maker's electricity consumption and greenhouse gas emissions.
Prof Sahajwalla said it was crucial for manufacturers and researchers to come up with commercially viable new methods.
"Climate change and clean energy narratives often overlook the need for more sustainable manufacturing and waste management practices, where we start to use waste resources for future manufacturing needs," she said.
"Natural resources alone will not deliver the feedstock supply for all of society's needs, so we need a far more sustainable approach."
She urged all manufacturers to engage with a local university or TAFE and challenge them with a business issue that needs solving.
"Conversely, I recommend researchers go out into the field and work with industry because there are really interesting, practical challenges to solve," she said.
Working with footwear manufacturer Crawford Boots and the Advanced Manufacturing Growth Centre as well as UNSW Sydney, the technology has bridged the often treacherous gap between research and commercialisation.
The technology of polymer injection into steel making is being used at Molycop's electric arc furnace (EAF) in Newcastle, where waste rubber from old tyres, conveyor belts and rubber safety boots is used as a substitute fuel.
Molycop president of sustainability Ian Tooze said they had successfully developed a product, process and system that will be offered to global EAF steel makers.
"This project proves that Australia can develop and, critically, commercialise new and innovative ways to address waste and emissions that also benefits steel makers' bottom lines and the environment," he said.
Penny Crawford, founder of Crawford Boots, said working alongside a large manufacturer and researchers had prompted her to look at the entire life cycle of products.
"From protecting the feet of workers in mines to how our boots are used at time of disposal, we now have revised our products to make them more suitable to polymer injection technology," Ms Crawford said.
"Collaborative programs like (Advanced Manufacturing Growth Centre's) lift the entire manufacturing industry," she said.
