Comment on In a U.S. First, a Commercial Plant Starts Pulling Carbon From the Air
SirStumps@lemmy.world 1 year ago
Unfortunately I can’t read the article. What do they do with the carbon once it’s collected? How are these powered? How much power does the collector use compared to how much it collects? If stored, where and how?
threelonmusketeers@sh.itjust.works 1 year ago
So they’re using the “limestone -> quicklime -> slaked lime -> limestone” cycle. The kiln must be powered by renewables (otherwise the process is pointless), but it’s a perfectly reasonable capture method.
Storage is slightly less straightforward. Concrete naturally absorbs carbon dioxide over decades, so this is just accelerating the inevitable.
Also the reason concrete can absorb carbon dioxide is that cement contains quicklime, which is mainly produced by… you guessed it, heating limestone to release the carbon dioxide! The concrete won’t absorb more carbon dioxide than was released during its production, so making excess concrete is not a solution. However, if the concrete was going to be produced anyway (and we produce a lot), I suppose it’s slightly better to have it absorbed carbon dioxide sooner rather than later.
Pumping carbon dioxide into underground storage wells a more scalable solution, provided that the local geology (olivine?) can absorb the carbon dioxide.
An alternative not discussed in the article is to reduce the carbon dioxide into various feedstock chemicals that we currently derive from fossil fuels. Again, this would need to be powered by renewables otherwise the process is pointless.
SirStumps@lemmy.world 1 year ago
You a wonderful. Thank you for this.
threelonmusketeers@sh.itjust.works 1 year ago
You’re welcome!)