Reinventing the steel industry for a green revolution
Liquid pig iron is injected into a chute at the blast furnace of the SSAB steel industry in Luleå, northern Sweden – Copyright GETTY IMAGES NORTH AMERICA / AFP / File Anna Moneymaker, WIN MCNAMEE
In a sparkling new building in the town of Lulea, in northern Sweden, steelmaker SSAB is using a new manufacturing method that could revolutionize the heavily polluting industry by eliminating almost all of its CO2 emissions.
But making the method work on a large scale poses major challenges, and the technique may not be the “silver bullet” that everyone is hoping for. Critics argue it could just push shows elsewhere.
Finding ways to decarbonize steel, an essential component of modern industry, is one of the keys to drastically reducing carbon emissions in order to meet climate goals.
Among heavy industries, iron and steel production is the biggest contributor to CO2 emissions, according to the International Energy Agency.
The World Steel Association estimates that the industry accounts for around seven to nine percent of the world’s anthropogenic emissions, with around 2.6 billion tonnes of CO2 emitted in 2020.
In Lulea, the sterile appearance of the new building stands in stark contrast to the nearby soot-covered blast furnace it is supposed to replace.
Lit by the characteristic orange glow of molten metal as liquid cast iron escapes, the blast furnace is the primary method of steel production today.
“By replacing the technology of a normal blast furnace where we use coal and emit CO2, we end up with ordinary water instead,” Monica Quinteiro, head of the SSAB site, told AFP. a visit to the HYBRIT pilot plant.
“We can reduce CO2 emissions from the steel industry by 90%,” she adds.
HYBRIT is a collaboration between the steelmaker SSAB, the state-owned company Vattenfall and the mining company LKAB.
– Remove oxygen –
The iron ore that comes out of a mine is usually rich in oxides, chemical compounds made up of iron and oxygen, the most well-known form of which is rust.
To make steel, this oxygen must be removed.
Air heated to over 1,000 degrees Celsius (1832 F) is introduced into the blast furnace, causing the coke to react with oxygen which is then released as CO2, resulting in nearly two tons of CO2 for every ton of steel produced.
In the HYBRIT installation, oxygen is evacuated differently.
“Instead of using heated air, we circulate hot hydrogen gas,” explains Quintero.
Hydrogen, like the carbon in coke, binds to the oxygen in iron ore, creating water instead.
While so-called direct iron reduction is not entirely new, HYBRIT sets itself apart by using hydrogen – produced by electrolysis – and ensuring that all electricity in the production process is of renewable origin.
While steel is mostly iron, carbon must be added.
“But it’s a very, very small amount that we have to add at the end of the manufacturing process,” Martin Pei, technical director of SSAB and initiator of the HYBRIT project, told AFP.
If the successful pilot project can be scaled up, “We can basically solve the root cause of the CO2 emissions,” says Pei.
– Challenges remain –
In August, SSAB shipped the first batch of steel plate – 25 tonnes – made with the new process – which it labels fossil-free – to truckmaker Volvo.
That’s a drop in the ocean compared to the 1.86 billion tonnes of steel shipped by steelmakers in 2020, according to the World Steel Association.
But SSAB aims to produce 1.5 million tonnes of “fossil-free steel” per year by 2026, up from its current production of 7.5 million tonnes per year.
The biggest barrier to large-scale production is access to electricity, especially that produced from renewable sources.
To operate on a large scale, SSAB would need around 15 terawatt-hours (TWh) of electricity per year, and for its mining operations, LKAB needs 55 TWh.
Together, this represents around a third of Sweden’s total electricity consumption.
– Hidden costs? –
Not everyone is a fan of the approach.
“It requires huge amounts of electricity at a time when electricity production is already under strain,” Christian Sandstrom, associate professor at Jonkoping International Business School, told AFP.
Sandstrom and two colleagues wrote an article criticizing the project in October and questioning the “fossil-free” label.
“The net effect of this hydrogen-based steel is higher electricity consumption and from what we can see there is no sign that electricity is going without fossil fuels,” said Sandstrom said.
SSAB’s production increase would hardly reduce steel emissions globally: in terms of tonnage, SSAB was only ranked 52nd among global steel producers in 2020, according to World Steel Association.
But others are betting it may be the future.
In February, the new Swedish company H2 Green Steel announced plans to build a facility that would be operational in 2024.
And China’s HBIS, the world’s third-largest steel producer, announced in May that it had started production at a demonstration facility for its own direct reduction of iron using hydrogen.