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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."
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."
The process sounds a lot like how aluminum gets refined. Aluminum doesn't exist in nature as a pure metal - the ores (primarily bauxite) are mostly aluminum oxides. To break apart (reduce) the oxides, huge electric currents are used: a battery in reverse. (This is why a lot of aluminum refining happens in places with lots of cheap electricity - Canada, Iceland, etc.)
In traditional iron smelting, the oxides are reduced by the addition of carbon in a blast furnace, producing CO and CO2 as a waste product. Replacing the chemical, carbon-based process with an electrical process would indeed be beneficial.
> 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.
Indeed the correct number is about 4%, which is still huge but is less than half of 10%.
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I agree that cars are important, but globally transportation only accounts for ~15% of CO2 emissions and even in the US it's ~28%. And that's all transportation, not just cars.
The above recollection is not correct. Coke was considered an improvement in quality, and brought about an "alteration which all England admired"—the coke process allowed for a lighter roast of the malt, leading to the creation of what by the end of the 17th century was called pale ale. The coke production process was not known since the 1500s. A more primitive process existed and was the reason why it was not popular for use in the production of iron. "In 1709, Abraham Darby I established a coke-fired blast furnace to produce cast iron. Coke's superior crushing strength allowed blast furnaces to become taller and larger. The ensuing availability of inexpensive iron was one of the factors leading to the Industrial Revolution." Additionally, "in 1768 John Wilkinson built a more practical oven for converting coal into coke. Wilkinson improved the process by building the coal heaps around a low central chimney built of loose bricks and with openings for the combustion gases to enter, resulting in a higher yield of better coke. With greater skill in the firing, covering and quenching of the heaps, yields were increased from about 33% to 65% by the middle of the 19th century. The Scottish iron industry expanded rapidly in the second quarter of the 19th century, through the adoption of the hot-blast process in its coalfields."
IIRC actual blast furnaces are all in China and Korea these days.
Huge fuckers are now sunk costs, unless there is a process breakthrough, they are unlikely to be replaced.
Steel mills in the west make boutique alloys, usually out of scrap.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
And cement absorbs CO2 when it sets, so the actual non hysterical number is even lower.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
Agriculture is about 9% of emissions. Transportation is 28% and electricity production is another 28%. So you typing on your computer is directly funding it; keystroke by keystroke.