Nine publications on our green steel advances

In this new feature story, published by Nine publications, journalist Nick O'Malley writes about UNSW SMaRT Centre's new Green Steel Polymer^TM Injection Technology research aiming to remove coking coal from steel making.

Read the full story on the SMH or The Age websites which has been syndicated to various other Nine publications including WA Today and Brisbane Times.

Here is an excerpt:

In a world desperate to go green, a NSW steel town is providing a solution

By Nick O'Malley, National Environment and Climate Editor for The Sydney Morning Herald and The Age

31 March 2023

Up close, an electric arc furnace has an overwhelming, elemental presence. Even with hearing protection and safety gear on, even behind the thick protective glass of the control booth, the heat and light exploding from the machine is startling.

Outside the booth the scream of the furnace as it begins to pour steel from its gullet renders even shouted conversations moot.

Steelmaking is known to be at least 4000 years old, and in this steelworks in Newcastle the process still looks like something ancient: slag bubbles away on top of a cauldron of boiling molten metal in a darkened chamber of gantries, cables, and pipes coated in a fine thick grime.

In fact, what has been going on in this room in recent weeks is at the leading edge of global steelmaking technology.

Green steel operating in a MolyCop furnace in Newcastle.

As world leaders prepare for the COP26 climate talks in Glasgow in November, momentum is building in a movement to have them agree to rapidly phase out the use of thermal coal, which is burnt in power stations to make electricity and is the single largest source of global greenhouse gasses.

No similar movement exists to drive out the use of metallurgical coal, because, until recently, steel production without it was inconceivable. But technological breakthroughs in steelmaking in Sweden and in Australia are changing that.

“There will be a time, soon, when we can make not just steel but all the metals we need without using coal,” Professor Veena Sahajwalla, director of the University of NSW’s Centre for Sustainable Materials Research and Technology, said.

Each tonne of steel produced creates about two tonnes of carbon dioxide. It is released in the creation of the energy used in the production process and as a gas from the coal as it is burnt in the furnace to provide both carbon and hydrogen crucial to the steel making process.

Professor Veena Sahajwalla, at a laboratory furnace at the UNSW SMaRT Centre.

Working with the steelmaker Molycop, scientists from the University of NSW have commercialised a process that replaces coking coal with rubber from used tyres, dramatically reducing the amount greenhouse gasses emitted per tonne of steel produced.

With the process proved, Molycop is in talks to license the technology to a world desperate to clean up steelmaking as it grapples with global warming.

Steel is the world’s single most important engineering and construction material. It is bound so closely to human development that its use surges in lockstep with wealth generation in growing economies like China.

But making steel is a dirty business.

The World Steel Association estimates that in 2021 the global steel industry used about 2.3 billion tonnes of iron ore, 1.1 billion tonnes of metallurgical coal and 680 million tonnes of recycled steel to produce 1.95 billion tonnes of crude steel. In doing so, it dumped about 2.6 billion tonnes, or nearly 10 per cent, of the world’s greenhouse gases into the atmosphere.

Steel is generally made from one of two processes.

In one, iron ore is refined and then combined in a coal-fired blast furnace with coke (which in turn is made of metallurgical coal purified in extreme heat) to provide ingredients such as hydrogen and carbon.

In the other, scrap metal is melted in an electric arc furnace along with coke, which again provides hydrogen and carbon.

At present, there are about 600 electric arc furnaces in the world, representing about 30 per cent of the world’s steel making capacity. They are concentrated in the older advanced economies such as North America and Europe, where there is a more ready supply of scrap steel to feed them. They are becoming more common in China and other parts of Asia as the supply of scrap grows.

It is this use of scrap that attracted the attention of Professor Veena Sahajwalla, who now heads the University of NSW’s Sustainable Materials Research and Technology (SMaRT) centre.

At present, there are about 600 electric arc furnaces in the world, representing about 30 per cent of the world’s steel making capacity. They are concentrated in the older advanced economies such as North America and Europe, where there is a more ready supply of scrap steel to feed them. They are becoming more common in China and other parts of Asia as the supply of scrap grows.

It is this use of scrap that attracted the attention of Professor Veena Sahajwalla, who now heads the University of NSW’s Sustainable Materials Research and Technology (SMaRT) centre.