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.
Steelmakers worldwide are facing mounting pressure from government regulators and consumers to decarbonize operations. Doing so is essential to limiting global warming to 1.5 degrees Celsius and staving off most of the worst effects of climate change, experts say.
In recent months, the world’s three top producers — Europe’s ArcelorMittal, China’s Baowu Steel, and Japan’s Nippon Steel — committed to achieving net-zero emissions by 2050, echoing targets set in their home countries.
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