About 70 percent of steel today is made how it’s always been
made: in giant, extremely hot furnaces. Purified coal, or
“coke,” is heated and melted with iron oxide and limestone,
then injected with oxygen to reduce the carbon content of
the mixture and to remove impurities.
Coal’s grip on the global electricity sector is loosening as more utilities and companies invest in renewable energy. But one major coal consumer — the steel industry — is finding it harder to kick its habit.
Steel companies make nearly 2 billion tons of high-strength material every year for bridges, buildings, railways, and roads. The furnaces that melt iron ore to make steel consume vast amounts of coal.
As a result, the industry accounts for roughly 8 percent of annual carbon dioxide emissions, as well as a toxic soup of air pollutants. Continue Reading →