5 HN users recommended this explainer5 months2021–2026score 5
Years with an HN recommendation, 2007–2026
Go-to link when oxygen candles, CO2 capture or submarine air quality come up.
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.
“Smarter Every Day did an interesting series of videos about nuclear submarines.” (HN, 2022)
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]
Covers submarine atmosphere management including CO2 scrubbing around 20 minutes.
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.
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]
Great introduction to submarine oxygen generation.
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]
Educational series aboard a nuclear sub; oxygen episode especially enlightening.
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]
Shows oxygen candles used to replenish submarine air.
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.
Shows burned and fresh oxygen candles on a submarine.
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]
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).
I don't know why this makes me think of it but the coolest "burning" thing has to be an "Oxygen Candle" [link] [link] [this video] Unfortunately they are "boring" in comparison, no flame/glow
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