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Efficient method to capture carbon dioxide from the atmosphere

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Re: Efficient method to capture carbon dioxide from the atmosphere

#221

Post by ethbr1 »

blacksqr wrote: post #211

The best carbon capture device is the ocean, and for the last 10 years or so huge amounts of free-floating sargassum seaweed have grown in warm ocean waters around the world. Nobody is certain why the sargassum has appeared in such volume lately, but it's plausible to speculate that increased CO2 in ocean water plays a role. As far as I can see the only remotely efficient way to sequester carbon at scale is to levera…

> for the last 10 years or so huge amounts of free-floating sargassum seaweed have grown in warm ocean waters around the world

For those curious about numbers for 2025, a couple links: https://optics.marine.usf.edu/projects/SaWS/pdf/Sargassum_ou... https://abcnews.go.com/International/scientists-concerned-re...

> Nobody is certain why the sargassum has appeared in such volume lately

For the record 2025 volumes specifically, the ABC article notes that sudden phosphorus flushes as a result of multi-year drought-hit watersheds finally being flushed out likely contributed. Ocean ecology at scale is usually highly correlated with nutrient density.

Re: Efficient method to capture carbon dioxide from the atmosphere

#222

Post by constantcrying »

People need to keep in mind how rare CO2 is in the atmosphere. It currently is at around 420 ppm and was at around 100 ppm less in the 60s. CO2 is a miniscule part of the atmosphere, which is why large relative changes are caused by human activity.

To remove 10ppm of atmospheric CO2 from the atmosphere (which would do nothing to sustainably lower CO2 in the atmosphere) would require processing 10ppm of the entire atmosphere. That is one in 100.000 parts of the atmosphere. The entire atmosphere is around 5x10^18 kg, so we need to process 5x10^13 kg of air. Which is 50 million million (no typo) kilos of air.

The industrial task of doing this unfathomably large and by itself would have no long term Impact.

Human fabricated carbon capture from ambient air is a complete fools errand only promoted by the scientific illiterate or those who benefit from scientific illiteracy. You can essentially just look at the first graph on wikipedia and see that it is never going to work: https://en.wikipedia.org/wiki/Carbon_dioxide_in_the_atmosphe...

Re: Efficient method to capture carbon dioxide from the atmosphere

#223

Post by [deleted] »

saubeidl wrote: post #91
PeterHolzwarth wrote: post #84

Well, instead of repeating myself manually, I'll paste in a comment of mine here from a past discussion on carbon capture: It's easy to forget why there is a bit of a challenge to getting C02 out of the air: there's so little of it, comparatively. In order, air is, broadly, made up of the following: Nitrogen: %78.084 Oxygen: %20.946 Argon: %00.934 CO2: %00.042 The stuff is essentially beyond a rounding error - it rea…

What if one started emitting Nitrogen, Oxygen and Argon in the right proportions instead to get the mix right again?

[deleted]

Re: Efficient method to capture carbon dioxide from the atmosphere

#224

Post by pigpop »

teiferer wrote: post #99
jmclnx wrote: post #41

Earlier quoted context omitted.

I agree, plus were would one store the CO2 ? To get back to "1980", I really doubt puling CO2 from the atmosphere will ever work. Another concern, who will pay for maintenance ? See this for why you cannot let CO2 escape from underground storage: https://en.wikipedia.org/wiki/Lake_Nyos_disaster If stored near a populated area, hundreds of thousands could be kill, including all animals and insects, in a matter of minu…

> I would rather live near a nuclear waste site than a CO2 Site. If it's between immediate death and a slow one of cancer, I'm not sure your choice is the obvious one.

A failure in containment at a nuclear waste storage site means danger for people on the site itself but it is easily detected by monitoring equipment and can be repaired, the waste is solid and can't spread easily. A failure in containment of a massive quantity of pressurized CO2 would be significantly more dangerous and probably a lot more likely to happen given the frequency of accidents

https://aiche.onlinelibrary.wiley.com/doi/abs/10.1002/prs.68...

https://www.youtube.com/watch?v=zkWeZ1YPI88

https://www.youtube.com/shorts/H1rWZHNWBWo

Re: Efficient method to capture carbon dioxide from the atmosphere

#225

Post by progbits »

ifwinterco wrote: post #169
progbits wrote: post #156

Earlier quoted context omitted.

https://www.sciencedirect.com/science/article/pii/S036013232... > In this study, a systematic review and meta-analysis of fifteen eligible studies was performed to quantify the effects of short-term CO2 exposure on cognitive task performance. > The complex task performance declined significantly when exposed to additional CO2 concentrations of 1000–1500 ppm and 1500–3000 ppm

It looks like there might be a very small effect starting at around 1000ppm but so small that many studies find no difference at all, and reliable effects are only noted at 3000ppm or more. So we're a long way from needing to scrub co2 from the atmosphere to get any work done

Not from atmosphere but we need good ventilation. Over 2000ppm in offices is very common.

Re: Efficient method to capture carbon dioxide from the atmosphere

#226

Post by loeg »

dylan604 wrote: post #220
loeg wrote: post #203

Earlier quoted context omitted.

What do you think happens to harvested wood?

why do you think it will only be used as fuel? it can also be used to build things with it

I didn't say fuel. It also rots when used as a building material.

Re: Efficient method to capture carbon dioxide from the atmosphere

#227

Post by [deleted] »

wcoenen wrote: post #191
progbits wrote: post #157

Earlier quoted context omitted.

See my sibling comment for meta-analysis that disagrees with you. Would love to see citation for those navy experiments.

Citation for a 2018 study with submarine-qualified sailors: https://pubmed.ncbi.nlm.nih.gov/29789085/

[deleted]

Re: Efficient method to capture carbon dioxide from the atmosphere

#228

Post by beachy »

orbital_laser wrote: post #210
beachy wrote: post #196

Earlier quoted context omitted.

Removing CO2 from the air is a pipe dream for several obvious reasons. Firstly, it will always be more difficult and energy-intensive to extract CO2 than to just stop putting it into the atmosphere in the first place. Yet the world is nowhere near agreeing any meaningful framework on reducing emissions, and the party in power in the largest democracy in the world is in denial that a problem even exists. But mainly, i…

Stop writing confident rhetorical takes on about which you know nothing.

You really created an account to post this?

Re: Efficient method to capture carbon dioxide from the atmosphere

#229

Post by thunderbong »

PeterHolzwarth wrote: post #84

Well, instead of repeating myself manually, I'll paste in a comment of mine here from a past discussion on carbon capture: It's easy to forget why there is a bit of a challenge to getting C02 out of the air: there's so little of it, comparatively. In order, air is, broadly, made up of the following: Nitrogen: %78.084 Oxygen: %20.946 Argon: %00.934 CO2: %00.042 The stuff is essentially beyond a rounding error - it rea…

I get what you're saying, but couldn't this be used in a place with high concentrations of CO2, like factory chimneys?

Re: Efficient method to capture carbon dioxide from the atmosphere

#230

Post by rayiner »

jmward01 wrote: post #114

I am not against doing research in this area, please do, it is interesting and likely has many applications but global CO2 removal isn't one of them. Nothing proposed, including this, is within any orders of magnitude of a viable solution. The only solution we have is put less in the air in the first place. This tech looks interesting for transporting CO2 but that doesn't mean it sequesters it and even if sequestrati…

> The only solution we have is put less in the air in the first place

That’s not a solution either, because the developing world is not going to stop increasing their CO2 output until they fully industrialize. They’re just not. Feel free to seek reductions where you can, but don’t think of it as a solution because it’s not.

The technical problems with CO2 capture are far more solvable than the sociological problems with net zero emissions.

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