Climate change As the world turns to coal, scientists work on green steel
SSAB plans to produce 1.3 million tonnes of green steel per year by 2026.
In Australia, Professor Sahajwalla is leading a team that has developed another form of green steel.
In their process, already used around the world, the coal is replaced in the kiln by used car tires which, when heated, release both carbon and hydrogen.
But Professor Sahajwalla, who has become a world leader in the field of industrial recycling, is not yet satisfied. His team is working with global mining and metallurgical company MolyCop at its Newcastle plant to further refine the process.
They are developing a method of recycling steel in which the coal is replaced not only by tires, but also by a variety of wastes including plastics, electronic waste stripped of their metal components and even coffee grounds.
A BHP forecast released this year recognized that new processes would replace coking coal, but it expected traditional furnaces to still produce the vast majority of steel in 2050.
But mining magnate Andrew “Twiggy” Forrest, who invests in hydrogen technology, said he believed the coal shift would occur “almost violently.”
“I don’t think there will be a coal-fired blast furnace in operation by 2050. Period.”
“I don’t think there will be a coal-fired blast furnace in operation by 2050. Full stop,” he said in March.
Professor Sahajwalla believes that if we are to properly address not only global warming, but also the wider damage we are causing to the environment, we will have to learn to regard what we today call waste as precious resources, to reuse endlessly and discard.
A low-carbon economy will be almost entirely electrified, says Prof Sahajwalla, and most of the critical elements needed in the process – such as zinc, manganese and cobalt – are routinely thrown away.
“It drives me a little crazy to see an old remote control thrown in with batteries like it’s nothing,” she says.
The Morning Edition newsletter is our guide to the most important and interesting stories, analysis and ideas of the day. register here.