A New Method To Produce Steel Could Cut 5 Percent of CO2 Emissions (technologyreview.com)

An anonymous reader shares an excerpt from a report via MIT Technology Review: A lumpy disc of dark-gray steel covers a bench in the lab space of Boston Metal, an MIT spinout located a half-hour north of its namesake city. It's the company's first batch of the high-strength alloy, created using a novel approach to metal processing. Instead of the blast furnace employed in steelmaking for centuries, Boston Metal has developed something closer to a battery. Specifically, it's what's known as an electrolytic cell, which uses electricity -- rather than carbon -- to process raw iron ore.

If the technology works at scale as cheaply as the founders hope, it could offer a clear path to cutting greenhouse-gas emissions from one of the hardest-to-clean sectors of the global economy, and the single biggest industrial source of climate pollution. After working on the idea for the last six years, the nine-person company is shifting into its next phase. If it closes a pending funding round, the startup plans to build a large demonstration facility and develop an industrial-scale cell for steel production. The process to produce steel results in around 1.7 gigatons of carbon dioxide being pumped into the atmosphere annually, "adding up to around 5 percent of global carbon dioxide emissions, according to a recent paper in Science," MIT Technology Review reports.

The electrolytic cell that Boston Metal developed was realized after it was proposed to be used to extract oxygen from the moon's surface. "The by-product was molten metal," the report says. "But producing something like steel would require an anode made from cheap materials that wouldn't corrode under high temperatures or readily react with iron oxide. In 2013, [MIT chemist] Sadoway and MIT metallurgy researcher Antoine Allanore published a paper in Nature concluding that anodes made from chromium-based alloys might check all those boxes."

Comments

Re:The carbon in steel is CO2 neutral??

[Maury Markowitz]

> I thought that the carbon in steel making was charcoal deriving from trees?

Yikes, dude, they stopped doing that 200 years ago.

They used to use charcoal because it contains very few contaminates. The process of making it, which is lengthy and energy intensive, burns off many of the remaining nasties. However, the cost of making it, and the amount of wood it required, was astonishing, and was the primary reason steel was so expensive.

Everyone knew that coal was cheap and plentiful, but when you tried to use it for steel production the results were useless. Today we know that the problem is the sulphur content, which at the time was simply it's "offensive odour". The solution was found, IIRC, the beer breweries, who were going out of business because they couldn't afford wood to burn because the steel makers were using it all up (one of the reasons lager/pilsner became so popular). They found that if you heated the coal it would off-gas, and when that stopped the result is "coke" and burns clean. This had been known since the 1500s, but never became popular until there was a need for it.

Adopting coke for steel production was one of the great advances of the 18th century.

Re:Sounds like aluminum refining

[GameboyRMH]

Electricity is inefficient.

LOLWUT?

There's nothing inherently inefficient about electricity and it's used in our most efficient methods of converting potential energy to kinetic energy (electric motors), moving energy long distances (high-voltage lines including superconducting lines), and heating and cooling (electric heat pumps).

The reason "the hip thing to do is to electrify everything" is because it's generally more efficient, and even when it isn't (in which case it usually just about matches other methods), it gives greater flexibility in energy sources.