CRU: How Blast Furnaces Can Be Idled

The global Covid-19 outbreak has resulted in sharply falling steel demand all over the world. For the steel industry, it is a challenging task to reduce production levels as ~70 percent of global output is produced through the BF/BOF, or integrated steelmaking, process route. Blast furnaces (BFs) suffer from low operational flexibility—they cannot typically be operated below ~75 percent of nominal capacity for operational and costs reasons—but switching off can be a difficult, risky and expensive process, which puts mills in a challenging position when markets contract significantly. So, what does it actually mean to idle a blast furnace?

BFs are, by nature, complicated and expensive to halt. In this insight, we aim to illustrate the techniques to idle a BF in the short term, meaning it is relatively easy to bring it back to production. There is also a longer-term option, for which a BF remains out of operation for longer time periods, but with high restart costs.