From [0] the UK's steel industry apparently accounts for 2.4% of all emissions, so clearly a huge chunk of the (small) UK steel making industry.
I've seen guestimates of the total cost to fully decarbonise the country going into the trillions, so on face value this would appear value for money or perhaps low hanging fruit.
[0] https://researchbriefings.files.parliament.uk/documents/CDP-...
If you're interested, I discuss the general danger of working with such quick-grab numbers in https://climateer.substack.com/p/numbers.
FWIW from the same gov source "The blast furnace route forms the majority of UK and global steel production. In 2018, 82% of UK steel (5.9 million tonnes) was produced using the blast furnace route at Tata Steel’s Port Talbot site and British Steel’s Scunthorpe site. The Government estimated that 95% of iron and steel industry emissions (and around 15% of total industrial emissions) come from the Scunthorpe and Port Talbot blast furnace sites."
It does not differentiate between the two, though.