Another attempt at CCS...

[AE-NMidlands]

https://www.bbc.co.uk/news/articles/cr788kljlklo has

the process begins by treating some of the seawater to make it more acidic. This encourages the carbon that's dissolved in the seawater to turn into a gas and be released into the atmosphere as CO2.
"This is the seawater stripper" Prof Bell says with a smile as we turn a corner.
The "stripper" is a large stainless steel tank which maximises the amount of contact between the acidic seawater and the air.
"When you open a fizzy drink it froths, that's the CO2 coming out." Prof Bell says. "What we're doing by spreading the seawater on a large surface area. It's a bit like pouring a drink on the floor and allowing the CO2 to come out of the seawater really quickly."

The CO2 that emerges into the air is sucked away and then concentrated using charred coconut husks ready to be stored.
The low-carbon seawater then has alkali added to it – to neutralise the acid that was added – and is then pumped back out into a stream that flows into the sea.

I wonder what the carbon footprint of the initial acid dosing and then the neutralisation chemicals is? And how the coconut shell charcoal will be stored to prevent any fires or the CO₂ coming off. In sealed steel drums?

If we're looking to collect it up I don't know why they don't trap it from all the fermentation processes (Beer, spirits and wine) where it is coming off already concentrated, almost 100%

[MikeNovack]

If we're looking to collect it up I don't know why they don't trap it from all the fermentation processes (Beer, spirits and wine) where it is coming off already concentrated, almost 100%

Well, looked at another way, the CO₂ released by fermentation is net zero. After all, the CO₂ now being released when the sugars are fermented had earlier been removed from the air when the plant produced those sugars by photosynthesis.

It's like my releasing CO₂ by heating this place by burning wood. That is different from burning fossil fuels. I have 87 acres of trees busily converting CO₂ into cellulose, many times faster than I am burning some of it. Well only part of the plant ends up as wine, beer, etc. so the rest of the plant represents fixed CO₂

NOTE: This is climate related. In my climate (and yours) the plant residues do not rot as fast as they are produced. Organic matter builds up in the soil (soil HERE is <15. ,000 years old, post glacier). In much hotter climates this is not true and soils remain "mineralized". One of the threats we face with global warming is thawing of areas now permafrost where with thawing, more rotting will take place.

[AE-NMidlands]

If we're looking to collect it up I don't know why they don't trap it from all the fermentation processes (Beer, spirits and wine) where it is coming off already concentrated, almost 100%

Well, looked at another way, the CO₂ released by fermentation is net zero. After all, the CO₂ now being released when the sugars are fermented had earlier been removed from the air when the plant produced those sugars by photosynthesis.

It's like my releasing CO₂ by heating this place by burning wood. That is different from burning fossil fuels. I have 87 acres of trees busily converting CO₂ into cellulose, many times faster than I am burning some of it. Well only part of the plant ends up as wine, beer, etc. so the rest of the plant represents fixed CO₂

NOTE: This is climate related. In my climate (and yours) the plant residues do not rot as fast as they are produced. Organic matter builds up in the soil (soil HERE is <15. ,000 years old, post glacier). In much hotter climates this is not true and soils remain "mineralized". One of the threats we face with global warming is thawing of areas now permafrost where with thawing, more rotting will take place.

I don't think it matters one jot where it comes from: why isn't it worth going for what might be an easy win (where CO₂ is already pre-concentrated for you?) One molecule of CO₂ removed from the atmosphere or extracted from seawater is going to be just as useful whether it came from burning FFs or indirectly from a plant - which might well have "accidentally" used FF CO₂ instead of the virtuous molecules that (e.g.) I and others breathed out...

[Countrypaul]

https://www.bbc.co.uk/news/articles/cr788kljlklo has

the process begins by treating some of the seawater to make it more acidic. This encourages the carbon that's dissolved in the seawater to turn into a gas and be released into the atmosphere as CO2.
"This is the seawater stripper" Prof Bell says with a smile as we turn a corner.
The "stripper" is a large stainless steel tank which maximises the amount of contact between the acidic seawater and the air.
"When you open a fizzy drink it froths, that's the CO2 coming out." Prof Bell says. "What we're doing by spreading the seawater on a large surface area. It's a bit like pouring a drink on the floor and allowing the CO2 to come out of the seawater really quickly."

The CO2 that emerges into the air is sucked away and then concentrated using charred coconut husks ready to be stored.
The low-carbon seawater then has alkali added to it – to neutralise the acid that was added – and is then pumped back out into a stream that flows into the sea.

I wonder what the carbon footprint of the initial acid dosing and then the neutralisation chemicals is? And how the coconut shell charcoal will be stored to prevent any fires or the CO₂ coming off. In sealed steel drums?

If we're looking to collect it up I don't know why they don't trap it from all the fermentation processes (Beer, spirits and wine) where it is coming off already concentrated, almost 100%

I suspect, but it is not clear, that the coconut shell charcoal is used to remove impuities from the CO2 so leaving a purer gas for later storage. That woould result in the charcoal having very little difference carbon wise to how it started in this process, but could well have much higher levels of other contaminants.

[AE-NMidlands]

I should have thought of that, I'm afraid I tend to take things literally - and get very cross when professional so-called journalists get a story completely wrong!
However, it seems that activated charcoal is being looked at for Carbon capture. A web search found several articles and papers, like https://pubs.acs.org/doi/10.1021/acsomega.3c02476 "Activated Carbon as an Adsorbent for CO2 Capture"
I still wonder how they will keep the CO2 sequestered for the very long term, maybe make the AC into a slurry and pump it down a disused oil or gas well?

[MikeNovack]

I still wonder how they will keep the CO2 sequestered for the very long term, maybe make the AC into a slurry and pump it down a disused oil or gas well?

For very long term (geologic time) convert the CO₂ rich slurry to a carbonate. Usually CaCO₃. Bury the limestone wherever. But since already in a finely pulverized state, spread on the ground where the soil pH is too low for the plants you are trying to grow and let them make use of it (doesn't result in net release since the plants are taking up CO₂ as well as the Ca)

[AE-NMidlands]

I still wonder how they will keep the CO2 sequestered for the very long term, maybe make the AC into a slurry and pump it down a disused oil or gas well?

For very long term (geologic time) convert the CO₂ rich slurry to a carbonate. Usually CaCO₃. Bury the limestone wherever. But since already in a finely pulverized state, spread on the ground where the soil pH is too low for the plants you are trying to grow and let them make use of it (doesn't result in net release since the plants are taking up CO₂ as well as the Ca)

but we are trying to get the CO2 irrevocably out of the atmosphere and the carbon cycle now, and putting it anywhere that it is biologically available will defeat the whole purpose of the operation. The plants will only take it up on a temporary basis too.
I wonder how you get from CO2 adsorbed on carbon to CaCO3? Mix the slurry with quicklime? That has its own massive carbon footprint!

[MikeNovack]

but we are trying to get the CO2 irrevocably out of the atmosphere and the carbon cycle now, and putting it anywhere that it is biologically available will defeat the whole purpose of the operation. The plants will only take it up on a temporary basis too.

Did you miss the "climate related"?

What happens in your climate if you "sheet compost"? Say you had a slab of mineral soil (gravel, sand, clay) and on it you spread a layer of plant residue that grew in a comparable area. Is it all gone in a year, returned to CO₂ and H₂O? Or does some remain as a layer or organic matter? And if you repeated this year after year, what would you end up with?

We got into this mess by burning FOSSIL fuels, turning back to CO₂ Carbon that had initially had been deposited as organic matter on the surface but later got buried. Millions oy years worth in just a few human lifetimes. The Earth didn't start out with free Oxygen in the atmosphere. That Oxygen came into existence by green plants binding Carbon Dioxide into organic matter.

As to how the slurry becomes carbonate. ....... When CO₂ is in H₂O, ions result, weak Carbonic acid so will be HCo₃^- and CO₃⁼ ions. So if there are also Calcium ions, Ca⁺⁺ in the water CaCO₃ will precipitate out.

[Countrypaul]

but we are trying to get the CO2 irrevocably out of the atmosphere and the carbon cycle now, and putting it anywhere that it is biologically available will defeat the whole purpose of the operation. The plants will only take it up on a temporary basis too.

Did you miss the "climate related"?

What happens in your climate if you "sheet compost"? Say you had a slab of mineral soil (gravel, sand, clay) and on it you spread a layer of plant residue that grew in a comparable area. Is it all gone in a year, returned to CO₂ and H₂O? Or does some remain as a layer or organic matter? And if you repeated this year after year, what would you end up with?

We got into this mess by burning FOSSIL fuels, turning back to CO₂ Carbon that had initially had been deposited as organic matter on the surface but later got buried. Millions oy years worth in just a few human lifetimes. The Earth didn't start out with free Oxygen in the atmosphere. That Oxygen came into existence by green plants binding Carbon Dioxide into organic matter.

As to how the slurry becomes carbonate. ....... When CO₂ is in H₂O, ions result, weak Carbonic acid so will be HCo₃^- and CO₃⁼ ions. So if there are also Calcium ions, Ca⁺⁺ in the water CaCO₃ will precipitate out.

But if there was etnough free Calcium ions in the sea most of the dissolved CO2 would be converted to CaCO2 and we would not be looking at extracrtng the CO2 from the sea water.

[MikeNovack]

But if there was etnough free Calcium ions in the sea most of the dissolved CO2 would be converted to CaCO2 and we would not be looking at extracrtng the CO2 from the sea water.

Who said ANY human activity could result in a meaningful (percentage) increase in the amount of CO₂ removed from the oceans every day? There's an awful lot of marine organisms busily converting CO₂ and H₂0 to C₆H₁₂O₆ and O2. That's why there is Oxygen in Earths atmosphere.

Now if you PAY somebody to remove CO₂. so much per ton of Carbon, they may do that. Just don't expect it to make more than a tiny fraction ofr a percent difference.

Look, don't confuse the two. When we burn fossil fuels web might in a year convert back into CO₂ and H₂O what the plants fixed in a million years of working the opposite direction.