US company gets $120 million boost to make ‘green steel’

The manufacture of “green steel” moved one step closer to reality Friday as Massachusetts-based Boston Metal announced a $120 million investment from the world’s second- largest steelmaker, ArcelorMittal.

Boston Metal will use the injection of funds to expand production at a pilot plant in Woburn, near Boston, and help launch commercial production in Brazil. The company uses renewable electricity to convert iron ore into steel.

Steel is one of the world’s dirtiest heavy industries. Three-quarters of world production uses a traditional method that burns through train loads of coal to heat the furnaces and drive the reaction that releases pure iron from ore.

Making steel releases more climate- warming carbon dioxide than any other industry, according to the International Energy Agency — about 8% of worldwide emissions. Many companies are working on alternatives.

The financial package by global steel giant ArcelorMittal is the biggest single investment made to date by the firm’s carbon innovation fund. Microsoft is another investor.

Tadeu Carneiro, CEO of Boston Metal, said its technology is “designed to decarbonize steel production at scale” and would “disrupt the industry.”

The company’s technology was developed at the Massachusetts Institute of Technology. Professors Donald Sadoway and Antoine Allanore, experts in energy storage and metallurgy respectively, are the founders.

Instead of burning coal, their process runs electricity through iron ore in a metal box or “cell” the size of a school bus to separate the iron from the oxide. Operators then collect the liquid iron from the bottom, Carneiro said. Boston Metal said it can eliminate all carbon dioxide from its steel production and hopes to ramp up production to millions of tons by 2026. As a bonus, it said, it is able to extract metals from slag normally considered waste.

Steel is in the early stages of a transition to cleaner processes that have less impact on the climate.