British Steel is scrambling to find enough raw materials to keep steel production going at Scunthorpe, after the government took control of the plant on Saturday.
If the materials do not arrive in time then the end of production at at least one of the steelworks’ two blast furnaces could come within days.
The rush to secure materials such as coking coal and iron ore has put the spotlight on the workings of the UK’s last two blast furnaces.
Here’s what you need to know.
Why is there a race to find materials?
Scunthorpe’s “four queens” – four blast furnaces named Bess, Anne, Victoria and Mary – have towered over the town for decades. However, only two – Bess and Anne – are still in operation, and even those are faced with closure unless they can find raw materials to keep going.
British Steel’s Chinese owners, Jingye, had planned to turn off another as soon as on Monday – using a process called a salamander tap – ahead of stopping all operations within weeks, with 2,700 jobs at risk.
However, after taking control of the steelworks via emergency legislation on Saturday, the government has directed British Steel to reverse course and do everything it can to keep production going.
Why must blast furnaces be kept hot?
Steel is made from iron ore. The problem is removing the oxygen tightly bound to the useful iron. The blast furnace’s innovation – a key contribution from Britain to the Industrial Revolution – was using coal and temperatures above 1,000C to reduce the iron, which is drawn out constantly as a liquid from the bottom of the blast furnace. (The oxygen is – unfortunately for the climate – turned into carbon dioxide and vented into the air.)
Blast furnaces are essentially 100-metre towers with an opening at the top for iron ore and coal, and a tap on the bottom to let out molten iron. They run continuously – all through Christmas, pandemics or financial crises – so letting them cool by too much would waste energy. However, the bigger problem comes if the metal solidifies. Then the risk is an immovable lump of iron and other leftovers known as slag, which blocks the bottom, leaving the furnace beyond repair.
So what exactly is a salamander tap?
A salamander is a lizard-like amphibian, but for thousands of years in myth the creature was reputed to live in fire. The steel industry adopted the metaphor, using the word salamander to describe the remainders that sit at the very bottom of the furnace.
A salamander tap, then, is the process of drilling a hole in the bottom of the blast furnace to let out, or tap, that molten metal and slag. That process means that the blast furnace could in future be restarted.
Salamander taps are not unusual for blast furnaces. Over the decades in which they tend to operate, even the toughest materials lining the furnace break down and require replacement. That is possible only when the furnace has cooled, so tapping is required.
Why are British Steel’s management keen to avoid a salamander tap?
Working with molten metal is always dangerous, but technology such as remotely controlled drills has reduced the risk to life. However, costs can run into the millions of pounds, and the process requires a lot of preparation. It might be worthwhile for a blast furnace that will be restarted, but that calculation changes when a furnace is coming to the end of its life, as at Scunthorpe.
Going down to a single blast furnace would be likely to deepen losses at Scunthorpe: British Steel would be left with most of the costs, but with half the output. For a company already losing hundreds of millions of pounds, that would make recovery even harder.
Does keeping the blast furnaces going save Scunthorpe in the long term?
No. Anne and Bess are still thought to be in pretty bad shape after decades of under-investment under several owners. All blast furnaces wear out, but the consensus is that both the remaining furnaces at Scunthorpe are near the end of their lives.
However, the government wants to keep them going until cleaner electric arc furnaces can be built as a replacement. That would preserve jobs for at least a couple of years and retain British Steel’s customers – but building replacements could cost more than £1bn, which has not yet been committed.
