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The most famous carbon dioxide absorber

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Re: The most famous carbon dioxide absorber

#61

Post by elmolino89 »

londons_explore wrote: post #37

Anyone selling house-size CO2 absorbers to keep CO2 in my house to more like pre-industrial 200ppm rather than the 800ppm that's more common of house air in cities?

Probably way more important than lowering the CO2 is getting rid of PM2.5/PM10.

Rooftops nowadays are best used to mount solar panels. Some system growing circulating algae, be it on the roof or on the sun drenched walls while doable would have way higher at least the operating costs. Clining is one thing. If you live in the area with below zero temperatures either you drain the system or invest even more in some glasshouse, maybe thermal isolation at night or heating.

As mentioned by others, there are chemical solutions.

Re: The most famous carbon dioxide absorber

#62

Post by elmolino89 »

elmolino89 wrote: post #61
londons_explore wrote: post #37

Anyone selling house-size CO2 absorbers to keep CO2 in my house to more like pre-industrial 200ppm rather than the 800ppm that's more common of house air in cities?

Probably way more important than lowering the CO2 is getting rid of PM2.5/PM10. Rooftops nowadays are best used to mount solar panels. Some system growing circulating algae, be it on the roof or on the sun drenched walls while doable would have way higher at least the operating costs. Clining is one thing. If you live in the area with below zero temperatures either you drain the system or invest even more in some gla…

One can combine chemical absorber solution with electrolysis for the regeneration:

Efficient Direct Air Capture in Industrial Cooling Towers Mediated by Electrochemical CO2 Release

https://onlinelibrary.wiley.com/doi/10.1002/anie.202412697

Re: The most famous carbon dioxide absorber

#63

Post by teekert »

immibis wrote: post #59
teekert wrote: post #55

Earlier quoted context omitted.

I think measuring CO2 is mostly only useful as a proxy for how well you are ventilating (which is correlated to the health of your air unless outside air is filled with ie small particles or smog), and when you measure 800 ppm it is more than adequate. 800 is not doing anything to the body (that we know of). Do you want to use chemicals and devices that make the climate problem worse just to lower the CO2 concentrati…

IIRC 1000 is where it starts having easily detectable negative effects on human cognition, which means it has less easy to detect negative effects on human cognition at numbers lower than that.

If you own a CO2 sensor you know that even at 5000 it’s not “easily detectable”… I know what is said about cognitive abilities and CO2 but I guess that’s hard to feel yourself. Moreover I doubt those results. Humans start to die at 10%, that’s (if I’m not mistaken) 100.000 ppm.

Ive had a CO2 sensor for years, take it with me usually. In the beginning I was quite shocked, but I’m starting to doubt all the bad things said about CO2 over 1000-1500 ppm now…

Re: The most famous carbon dioxide absorber

#64

Post by acadavid79 »

tenpies wrote: post #29
josefritzishere wrote: post #8

Many of us knew the story from books, or even the Tom Hanks Apollo 13 film, but the detail here is fascinating.

Also for anyone interested, some of Flight Director Gene Kranz's recordings are available online. Here's the first part: https://www.youtube.com/watch?v=KWfnY9cRXO4 The comments have time stamps for some particularly interesting moments, but the incident occurs 8 minutes in, and the infamous "Houston, we've had a problem" remark happens at 9:20. The blog post talked about how everything had to be communicated verball…

And there’s also a site with replays of some Apollo missions. Several audio, video and data feeds. https://apolloinrealtime.org/13/mobile/

Re: The most famous carbon dioxide absorber

#65

Post by weard_beard »

schiffern wrote: post #51
HeyLaughingBoy wrote: post #20

Earlier quoted context omitted.

That would be one helluva parachute.

I don't know of any actual parachutes, but the closest thing is probably inflatable heat shields like HIAD or MOOSE. https://en.wikipedia.org/wiki/HIAD#Inflatable_heat_shield_en... https://en.wikipedia.org/wiki/MOOSE

My favorite goal in Kerbal Space Program is not the more common “return from a high gravity planet” or “orbit all the planets in the solar system in one trip” but instead “use every method including atmospheric air breaking, parachutes, and gravity assists, and mining resources /lunar/martian refueling to land a single stage rocket on mars and return”

Most fun thing to plan build and execute in the whole game IMHO

Bonus points if you bring and execute all types of science experiment available. This, and mining to refuel makes SSTO much harder.

*If you find this too easy then an upgrade is to do the same mission, but bring and deploy a permanent base to laythe (fictional moon of Jupiter with oceans). (bonus points if the base is mobile/submersible)

Re: The most famous carbon dioxide absorber

#67

Post by headsupernova »

teekert wrote: post #63
immibis wrote: post #59

Earlier quoted context omitted.

IIRC 1000 is where it starts having easily detectable negative effects on human cognition, which means it has less easy to detect negative effects on human cognition at numbers lower than that.

If you own a CO2 sensor you know that even at 5000 it’s not “easily detectable”… I know what is said about cognitive abilities and CO2 but I guess that’s hard to feel yourself. Moreover I doubt those results. Humans start to die at 10%, that’s (if I’m not mistaken) 100.000 ppm. Ive had a CO2 sensor for years, take it with me usually. In the beginning I was quite shocked, but I’m starting to doubt all the bad things s…

I've found the same. And thinking it through, I can't come up with a mechanism for how a few more CO2 molecules bopping around in a sea of nitrogen and oxygen changes anything about how my lungs exchange the CO2 in my body with air around me. These counts are ppm, nothing!

Re: The most famous carbon dioxide absorber

#68

Post by PNewling »

wpm wrote: post #47
changoplatanero wrote: post #41

Earlier quoted context omitted.

Not sure what city you live in but in the big cities I’ve lived in it was always easy to get the level down to 500ppm by opening windows.

Yeah I live in Chicago and it is not hard to keep it at 450ppm. Right now it’s 493ppm in here.

What are you using to measure this?

(I'm sure I could do my own research, but was more curious since it seems like you've already got a setup.)

Re: The most famous carbon dioxide absorber

#69

Post by kimixa »

teekert wrote: post #63
immibis wrote: post #59

Earlier quoted context omitted.

IIRC 1000 is where it starts having easily detectable negative effects on human cognition, which means it has less easy to detect negative effects on human cognition at numbers lower than that.

If you own a CO2 sensor you know that even at 5000 it’s not “easily detectable”… I know what is said about cognitive abilities and CO2 but I guess that’s hard to feel yourself. Moreover I doubt those results. Humans start to die at 10%, that’s (if I’m not mistaken) 100.000 ppm. Ive had a CO2 sensor for years, take it with me usually. In the beginning I was quite shocked, but I’m starting to doubt all the bad things s…

Air you breathe out is around 40 thousand ppm (and higher during exertion), and the air in the lungs isn't completely replaced every breath - I doubt there's much measurable difference at the actual alveoli at the levels we're talking about. You'll probably get more of a difference if you're breathing deeper and faster, or just got up to get a coffee or similar.

And interestingly there are studies that show that breathing in air up to 3% co2 (30k ppm) "did not substantially impair either cognitive and motor performance" [0]

[0] https://www.tandfonline.com/doi/epdf/10.1080/10803548.2007.1...

Re: The most famous carbon dioxide absorber

#70

Post by mppm »

londons_explore wrote: post #37

Anyone selling house-size CO2 absorbers to keep CO2 in my house to more like pre-industrial 200ppm rather than the 800ppm that's more common of house air in cities?

Honest question: Why would you want to? The average CO2 concentration in your lungs is something like 20,000 ppm, so it doesn't matter much whether ambient CO2 is at 200ppm or 800ppm. Other aspects of air quality do matter, but I'm highly skeptical about the value of capturing CO2 in your house.
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