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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

#201

Post by literalAardvark »

teiferer wrote: post #96
gonzo41 wrote: post #46

Earlier quoted context omitted.

Well as far as storing it goes, if you can capture it, turn it into a solid and stick it in the ground. Imagine you were growing a huge biomass that you harvest, dry out, and then store. We know how the bacteria and processes that stripped co2 from the atmosphere in the past, we just need to do that in a big way. Good thing we have places on earth that are huge and flat and growing algae won't be a problem. And then…

As long as leading figures either claim it's a hoax or that it's not necessary to do sth about it, none of this matters anywhere. This is less of a technogical problem than it is a political one, I'm afraid.

Not exactly less.

It's a science fiction grade engineering problem and a historically unprecedented political problem. That's a tough mix to crack.

It's worth trying to delay the end of civilization, but reversing this is literally like putting the fire back in the Molotov.

Re: Efficient method to capture carbon dioxide from the atmosphere

#202

Post by marcosdumay »

nine_k wrote: post #127
marcosdumay wrote: post #71

Earlier quoted context omitted.

> The ease of releasing CO2 is the key advantage of the new compound. I have no idea why the journalist that wrote this article choose to highlight the carbon density of the sub-header. It's almost completely irrelevant for carbon capture plants. Another clear benefit is that it's a liquid. Today people mostly use the substances that you called non-reversible in research plants (AFAIK, all plants are research right n…

> perfectly reversible, but that uses a lot of energy Looks like a perfect match to a solar plant, which provides basically free energy periodically. All you need is a large enough cistern to hold the liquid during night time.

Yes, it's a great match to solar plants.

But you don't need to store the capture medium. You use a bit more energy to make they work faster while the Sun is shining, and stop everything when it's gone.

The largest bottleneck is what you do to get rid of the CO2.

Re: Efficient method to capture carbon dioxide from the atmosphere

#203

Post by loeg »

dylan604 wrote: post #49
roflmaostc wrote: post #4

Earlier quoted context omitted.

The problem is you cannot plant enough trees around the globe to offset our CO2 emissions. Also, a forest only absorbs CO2 while alive. Once it dies, it emits CO2 too. You would need to permanently store the wood somewhere (submerging in water, etc). Recent article: https://www.theguardian.com/environment/2025/nov/28/africa-f...

If these forests are planted by humans, why do we think the dead trees would just be left to rot like you suggest vs being harvested for wood? The logic does not compute other than trying to make a ridiculous point.

What do you think happens to harvested wood?

Re: Efficient method to capture carbon dioxide from the atmosphere

#204

Post by hinkley »

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/

Have you ever met a submariner? These are not normal humans. That’s some serious cherry picking of data.

Re: Efficient method to capture carbon dioxide from the atmosphere

#205

Post by kbrkbr »

beachy wrote: post #196
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…

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…

> Removing CO2 from the air is a pipe dream for several obvious reasons.

For me at least both your arguments are not obvious.

There are a lot of things that are harder to put in the atmosphere than to remove them. Stones for example.

The second one is less of an argument, but rather a question. Why not the UN, the US, China, or Europe?

Re: Efficient method to capture carbon dioxide from the atmosphere

#206

Post by m0llusk »

It seems like the focus should be on capturing carbon dioxide from the oceans. Carbon dioxide in the atmosphere is extremely diffuse, but the oceans absorb it in large quantities and as a result it becomes much more dense which makes capture fundamentally more efficient.

Re: Efficient method to capture carbon dioxide from the atmosphere

#207

Post by hinkley »

progbits wrote: post #157
wcoenen wrote: post #126

Earlier quoted context omitted.

> Noticeable cognitive impairment starts in the 700-1000ppm range The US navy failed to detect such effects in submarine crew, even at much higher levels like 10,000 ppm. Another reason to be skeptical is that exhaled breath is 4% CO2 (40,000 ppm!). Therefore a few thousand extra ppm in the inhaled air should not make much of a difference to the homeostasis mechanisms in our bodies.

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

Back in the 00’s I worked at a place where we were still ignoring WLB and would work until seven a couple nights a week on average. But the building AC shut off at 6. A few of us noticed that the later it got the worse our decisions and the worse the bickering and we eventually got to the policy that anyone could declare Deciding done for the evening when they realized we were just tired, hot, and stuffy. Every minute past about 6:15 got worse, particularly in summer.

I’m sure the CO2 was part of it but lack of circulation also means increasing temperature, especially with a bunch of people in a small meeting room. Long meetings themselves are a problem and any excuse to call it early is probably worth it even if it’s not entirely true.

Re: Efficient method to capture carbon dioxide from the atmosphere

#208

Post by jmward01 »

akshatjiwan wrote: post #184
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…

I think you have a point. It could be difficult to justify the cost of carbon capture based on sequestration alone. One of the reasons I think this might still work is that captured carbon can be used to create platform chemicals (various hydrocarbons) using the fischer tropsch process. Electrofuels are using direct air capture to generate fossil replacements. Only requirement is energy and there too it isn't all tha…

I wonder what the economics could look like for using this with remote solar for production instead of considering it for global removal/sequestration. If you build a solar farm in a desert and use this to pull raw materials from the air to create something actually worth money, what levels of efficiency do you need to make that profitable? How close is something like that in reality?

Re: Efficient method to capture carbon dioxide from the atmosphere

#209

Post by hinkley »

nehal3m wrote: post #89
_yb2s wrote: post #67

Earlier quoted context omitted.

I think it’s little appreciated that high CO2 levels cause cognitive impairment, and with the same amount of (often very poor) air exchange, higher outdoor concentrations can push indoor spaces to levels that cause impaired cognition and poor sleep. I’ve already been seeing this in my home, and will often open windows even when cold just to keep co2 levels reasonable. One solution that can help is an external air hea…

>One solution that can help is an external air heat exchanger I have one of those, it blows fresh air in through the bedroom and sucks it back out through the kitchen (loft house, this route prevents food smells from wafting into the bedroom). Aside from just feeling fresh all year, this system also prevents mosquitoes from entering in summer while still allowing air circulation, it automatically bypasses the exchang…

I suspect bathrooms aren't big enough to buffer the air pressure but it seems like we should design the air handling so the “fan” is always on in the bathrooms. Maybe a split between several places and taking a bit from the cold air return for the rest.

Re: Efficient method to capture carbon dioxide from the atmosphere

#210

Post by orbital_laser »

beachy wrote: post #196
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…

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.
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