A Smarter Every Day episode from aboard a nuclear submarine on how the crew makes breathable air. It covers oxygen generation from seawater, oxygen candles and CO2 scrubbing with amine.
Why Hacker News points people here: Go-to link when oxygen candles, CO2 capture or submarine air quality come up.
“Smarter Every Day did an interesting series of videos about nuclear submarines.”HN comment, 2022
“Smarter Every Day did a video on it and atmosphere management on a submarine more generally which is pretty neat.”
Covers submarine atmosphere management including CO2 scrubbing around 20 minutes.
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Not sure if it's the same stuff exactly or if the cost includes reprocessing but there's an amine cycle that seems to be mostly closed that's used for CO2 removal on submarines. So it's just used to separate CO2 from the rest of the output. I think that's what this sentence is talking about: > Notably, it is projected that this solvent can operate at a regeneration heat rate of 2.0 GJ per tonne CO2 for post-combustion capture Smarter Every Day did a video on it and atmosphere management on a submarine more generally which is pretty neat. The CO2 scrubbing is around 20 minutes. this video
RecommendsnielsbotJun 2021
“You might find this series from Smarter Every Day interesting.”
Episode on how nuclear subs regenerate oxygen.
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You might find this series from Smarter Every Day interesting. this video I didn't find a bit about how they make drinking water, but here's an episode about how they regenerate their oxygen on a nuclear sub.
RecommendsCharlesWApr 2022
“I really enjoyed this Smarter Every Day episode that talks about maintaining air quality on a submarine”
Enjoyable episode on maintaining submarine air quality.
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I really enjoyed this Smarter Every Day episode that talks about maintaining air quality on a submarine: this video
RecommendsrdlMay 2022
“this is a great introduction to the topic”
Great introduction to submarine oxygen generation.
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Yes, but the context of this post was emergency systems which are purely chemical. For routine operations on e.g. a submarine, link As other people have mentioned, this is a great introduction to the topic: this video
RecommendshelsinkiandrewAug 2023
“The video on producing oxygen was particularly enlightening”
Educational series aboard a nuclear sub; oxygen episode especially enlightening.
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The SmarterEveryDay YouTube channel did a slightly more indepth series of videos aboard a nuclear sub, obviously still censored, but educational. link The video on producing oxygen was particularly enlightening: this video
Cites itnielsbotMay 2022
“Smarter Every Day did an interesting series of videos about nuclear submarines.”
Shows oxygen candles used to replenish submarine air.
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Smarter Every Day did an interesting series of videos about nuclear submarines. They use these candles to help replenish the oxygen in them: this video
Cites ittofofJan 2023
“shows the remains of a burned one and loading fresh ones on a submarine.”
Shows burned and fresh oxygen candles on a submarine.
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They burn at 600C (1100F) so I don't think you'd want to view the reaction directly; usually they have to be deliberately contained to contain the heat to sustain the reaction. this video (linked to correct timestamp) shows the remains of a burned one and loading fresh ones on a submarine.
Cites itRetricFeb 2023
Cited for how subs produce oxygen from seawater.
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Yea it produces chlorine. Nuclear subs need to use reverse osmosis first to get around that problem when they want to produce Oxygen from seawater. this video
Cites itshagieFeb 2023
Cited for submarine air handling methods.
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Submarines restock food, some air supplies, and... deal with waste. Food link Air this video (MEA and LIOH for CO2, electrolysis and "candles" for oxygen) Toilet link Nothing is "recycled" as such - and certainly not any of the carbon (you're not eating the carbon captured from MEA or LIOH... or your waste).
Cites itck2Apr 2026
Linked as example of oxygen candles.
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I don't know why this makes me think of it but the coolest "burning" thing has to be an "Oxygen Candle" linklinkthis video Unfortunately they are "boring" in comparison, no flame/glow
