Model suggests sequestering CO2 in deep sea sediments might be viable option

July 5, 2018 by Bob Yirka, Phys.org report
Schematic illustration of the infrastructure and related processes of carbon sequestration in deep-sea sediments. Credit: Yihua Teng and Dongxiao Zhang

A pair of researchers at Peking University has found evidence that suggests liquid CO2 could be safely sequestered in deep sea sediments. In their paper posted on the open access site Science Advances, Yihua Teng and Dongxiao Zhang describe a model they built to mimic CO2 injections beneath the ocean floor and what it showed.

As the planet continues to heat up due to the continued release of into the atmosphere, scientists look for other places to store them. Carbon dioxide has been singled out as one of the major greenhouse gases and because of that, efforts have been made to curb its release. Some approaches have focused on looking for ways to prevent is release, while others look for ways to capture and store it where it will not eventually leak into the atmosphere. One such place is in sediments that lie at the bottom of the ocean. But, as the authors note, little work has been done to find out if such a site might be able to hold CO2 without leakage into the water—and eventually into the atmosphere. In this new effort, the researchers built a model meant to mimic conditions and what might happen if liquid CO2 were injected into it.

One of the major culprits involved in releasing CO2 into the is coal-burning power plants. Work is currently being done to find ways to sequester the CO2 in these emissions. Such work has shown that CO2 can be captured and converted to various forms, from solids to liquids. It is the liquid form that the researchers with this new effort address.

Prior research has shown that when liquid CO2 is exposed to both high pressure and low temperatures, hydrates form. The researchers added this information to their model and then ran it multiple times under different conditions such as varying pressure and time scales. They found that under certain conditions, injecting CO2 into the sediments led to the formation of hydrates, which then served as a form of cap, preventing the CO2 liquid from seeping upward. They further found that over time, both the CO2 and the hydrates dissolved into pore fluids.

Emboldened by their results, the researchers suggest real-world studies of CO2 sequestration in seafloor sediments to determine if it is a viable solution.

Explore further: Study finds hydrate gun hypothesis unlikely

More information: Yihua Teng et al. Long-term viability of carbon sequestration in deep-sea sediments, Science Advances (2018). DOI: 10.1126/sciadv.aao6588

Abstract
Sequestration of carbon dioxide in deep-sea sediments has been proposed for the long-term storage of anthropogenic CO2 that can take advantage of the current offshore infrastructure. It benefits from the negative buoyancy effect and hydrate formation under conditions of high pressure and low temperature. However, the multiphysics process of injection and postinjection fate of CO2 and the feasibility of subseabed disposal of CO2 under different geological and operational conditions have not been well studied. With a detailed study of the coupled processes, we investigate whether storing CO2 into deep-sea sediments is viable, efficient, and secure over the long term. We also study the evolution of multiphase and multicomponent flow and the impact of hydrate formation on storage efficiency. The results show that low buoyancy and high viscosity slow down the ascending plume and the forming of the hydrate cap effectively reduces permeability and finally becomes an impermeable seal, thus limiting the movement of CO2 toward the seafloor. We identify different flow patterns at varied time scales by analyzing the mass distribution of CO2 in different phases over time. We observe the formation of a fluid inclusion, which mainly consists of liquid CO2 and is encapsulated by an impermeable hydrate film in the diffusion-dominated stage. The trapped liquid CO2 and CO2 hydrate finally dissolve into the pore water through diffusion of the CO2 component, resulting in permanent storage. We perform sensitivity analyses on storage efficiency under variable geological and operational conditions. We find that under a deep-sea setting, CO2 sequestration in intact marine sediments is generally safe and permanent.

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Doug_Nightmare
1.4 / 5 (10) Jul 05, 2018
What of the Precautionary Principle? Sequester a million tons of CO2 as hydrate, but lose control of the hydrate to what cost/hazard. Imagine Dr. No putting an atomic device in the middle of a giga-mole CO2 hydrate field.
antigoracle
1 / 5 (12) Jul 05, 2018
Another "brilliant" plan by the AGW Cult. This one even beats their bio-fuels from food crop idea. But then, when it comes to propagating their dogma, to hell with the consequences. These are the idiots who claim they are saving the world.
rrwillsj
3.6 / 5 (12) Jul 05, 2018
Trying to save the world, even though it appears to be a futile endeavor. Is still better than acquiescing to the denier shills screeching their gospel of greed and wastage. Are you really too stupid to comprehend the profits to be made in technical efficiency and methodical application of strategic thinking?
Eikka
1 / 5 (11) Jul 06, 2018
Trying to save the world, even though it appears to be a futile endeavor. Is still better


That's assuming you can do no wrong, that your efforts are necessarily beneficial.

"Just do something" isn't really a solution, because you can just as well make the situation worse - if only by making everyone run around wasting time and money for naught - and in fact there are so many people trying to leverage global warming to drive political agenda without care what happens to the climate.

"The sky is falling! Now gimme a dollar."
Eikka
1 / 5 (11) Jul 06, 2018
the profits to be made in technical efficiency and methodical application of strategic thinking?


Remember the preppers? People who bought into the fear that the world is ending soon enough that they have to buy guns and build bunkers - and there's a whole market to cater to these people, selling ever more ridiculous things with no warranties of actual function.

Well, there's a load of profit in the same way in lobbying for subsidies for industries which -pretend- to be solving the climate crisis, and these guys are pulling in the lion's share of the profits because they have products on the market while the real guys are still researching.

So, you get subsidized wind turbines, solar panels, electric cars... etc. which aren't cost effective, or effective in the general sense, aren't applied strategically, are causing more trouble than they're worth, but are still paid a ton by the public thanks to political scaremongering and corruption.

It just isn't helping
HeloMenelo
3.9 / 5 (11) Jul 06, 2018
Another "brilliant" plan by the AGW Cult. This one even beats their bio-fuels from food crop idea. But then, when it comes to propagating their dogma, to hell with the consequences. These are the idiots who claim they are saving the world.

Pea brain thumper here conveniently forgets about how his own stance for the filthy oil industry which btw relentlessly destroys the earth on a second to second basis, you say to hell with the consequences ???
Did i hear right ???????
Whats left of that pea brain if i might ask ???? Big oil sent their own consequences to hell many many MAAANY decades ago, and they are still keeping the coals on high with no end in site nor care in the world !!! And YOU DARE even TRY to talk about Consequences that does not even create a nano speck compared to filthy oil's worldwide Global destruction?????
ZoeBell
Jul 06, 2018
This comment has been removed by a moderator.
RealityCheck
3 / 5 (8) Jul 06, 2018
@ZoeBell.
So far the alarmists didn't manage to decrease fossil fuel consumption not least a bit
I know you are a very intelligent person, ZoeBell/Zephir; which is why it is perplexing to see you have obviously developed 'blind spots' when it comes to interpreting the data/evidence re AGW history/politics/science. Please realize the decades-long GOP/Fossil etc LOBBYISTS/MONEYS lies/corruption campaign delaying/ sabotaging efforts at CO2 mitigation/renewables action/policy/implementation; so you can blame THEM for fossil fuel use still being too high. :)
their methods of "renewables" increase fossil fuels consumption of background - just in another countries mining raws sources for their electromobiles and solar plants.
Please realize that such 'inputs' are NOT CONSUMABLES like coal/oil etc is. These things are ONE-OFF inputs which can be recycled/reused, so cleaner/safer, much less damage/cost longer term. :)

Time to stand back and rethinkit all, mate. :)
Thorium Boy
1 / 5 (4) Jul 07, 2018
Spending billions of dollars on industries that produce no products.
ZoeBell
Jul 07, 2018
This comment has been removed by a moderator.
humy
4.1 / 5 (13) Jul 07, 2018
Another "brilliant" plan by the AGW Cult.

Actually this one is supported more for those that want to burn fossil fuels without renewables; If you can burn it and sequester the CO2, you can burn it all without consequences. And there is no AGW 'Cult', just scientists and others that accept the scientific facts as facts. But there is your 'Cult'; the reality deniers.

humy
4 / 5 (12) Jul 07, 2018
Spending billions of dollars on industries that produce no products.

Electricity is a useful product.
Preventing disasters, such as excessive global warming etc, isn't a product but it is still highly desirable and beneficial so, why not?
TheGhostofOtto1923
1 / 5 (2) Jul 07, 2018
We ought to put the carbon some place where we can get it back in case we need it. You know, for future gens.

Probably easier to cool the planet than to warm it up.
antigoracle
1 / 5 (12) Jul 07, 2018
Spending billions of dollars on industries that produce no products.

Electricity is a useful product.
Preventing disasters, such as excessive global warming etc, isn't a product but it is still highly desirable and beneficial so, why not?
-- Yet Another Braying Chicken Little Jackass.

What is EXCESSIVE global warming? What is the "right" amount?
What makes global warming a disaster?

Intelligence and knowledge aren't products but are still highly desirable and beneficial, so, why not get some?
Eikka
1 / 5 (7) Jul 07, 2018
Please realize the decades-long GOP/Fossil etc LOBBYISTS/MONEYS lies/corruption campaign delaying/ sabotaging efforts at CO2 mitigation/renewables action/policy/implementation; so you can blame THEM for fossil fuel use still being too high


If it really works, there's real money to be made in it, and there's no conspiracy theory in the world that's going to stop that train.

As it is, renewables only make money as they're being subsidized, and when the subsidies run out, the investments into renewable energy go like a lead balloon.

That's an observable fact.

Most of the propaganda actually comes from the renewables side, because they need to justify the futility of the subsidies and over-paying for ineffective technologies. The message is, if you pay us now we'll eventually make something that works, but the problem is that as long as you're paying them for what they're offering now, there's no need for anyone to improve - you're already rewarding them as it is.
humy
4.1 / 5 (13) Jul 08, 2018
What is EXCESSIVE global warming?

enough so its benefits outweigh its costs. If the ice caps melt, it is more than excessive.
What is the "right" amount?
That is at most ill defined and partly subjective and there may be none but we already are definitely starting to see too much no matter how you look at it.
What makes global warming a disaster?
An excessive amount.
Intelligence and knowledge aren't products but are still highly desirable and beneficial, so, why not get some?
Your above stupid questions show you need some.
humy
4.2 / 5 (15) Jul 08, 2018

As it is, renewables only make money as they're being subsidized,

Please don't lie.
In many parts of the world renewables already provide the cheapest source of energy WITHOUT subsidies.
granville583762
1.8 / 5 (10) Jul 08, 2018
Death Wish III
Are we out of our tiny minds, sequestering CO2 is the same as sequestering Oxygen
We might as well be sequestering Humans, well they started - you did to !
HeloMenelo
4 / 5 (17) Jul 08, 2018

What is EXCESSIVE global warming? What is the "right" amount?
What makes global warming a disaster?

Intelligence and knowledge aren't products but are still highly desirable and beneficial, so, why not get some?


Saying the word "intelligence" does not mean you understand it's meaning, nor does it say you desire it or you can even pronounce it, that's something far out of reach for you and, even swinging high up in the trees like you and your dumbty socks do on a daily basis, won't get you anywhere close. SCIENCE have proved that about YOU antigoracle et 'al and your babbling baboon chatter time and again
granville583762
1.7 / 5 (11) Jul 08, 2018
RealityCheck where Oh where Oh are you in our hour of need!
Can you release this genie that is in imortal peril before the last carbon dioxide molecule is sequestered
Because RealityCheck; it will then be to late
granville583762
2 / 5 (4) Jul 08, 2018
It's not just us Ostriches are so dim, humans are so intelligent they outwit us!
Death wish one was just the first billion years, Death wish III is the third and final sequestration
CO2 is in terminal decline RealityCheck
RealityCheck where Oh where Oh are you in our hour of need!
Can you release this genie that is in imortal peril before the last carbon dioxide molecule is sequestered
Because RealityCheck; it will then be to late

When our tiny minds get out of the sequestering rut, we will realise plant life over the billions of years have already sequestered the bulk of the Earth's CO2 already, where our tails sticking out the sand as we bury that last CO2 molecules the Ostrich that's hiding from that voracious predator said "so it's not just us Ostriches that are dim, humans are so intelligent they outwit us!
antialias_physorg
5 / 5 (7) Jul 08, 2018
If you can burn it and sequester the CO2, you can burn it all without consequences.

Not really.
1) sequestering takes energy - likely a large chunk (or even more) than you got out of it in the first place. This makes fossil fuels even less economically viable than they already are.
2) Sequestration sites become saturated. It's like with garbage dumps: you don't have space to put an infinite number of them around
3) There's always the risk that all the sequestered stuff in one location will bubble up through a crack (due to e.g. an eartchquake). That would be pretty nasty for an entire region. For what would happen check the lake Nyos disaster.
https://en.wikipe...disaster
4) Fossil fuels are still a limited resource. Even if we can sequester CO2 we cannot use fossil fuels indefinitely.
5) Burning fossil fuels produces other harmful substances besides CO2
ZoeBell
Jul 08, 2018
This comment has been removed by a moderator.
granville583762
5 / 5 (1) Jul 08, 2018
Busy squirreling it away, tails in the air, sequestering!
Exactly "There's always the risk that all the sequestered stuff in one location will bubble up through a crack"
That is essentially where all are fossil fuel is - it is bubbling up all over the place antialias_physorg, with a little help from our selves, that is when were not busy squirreling it away, tails in the air, sequestering!
RealityCheck
1 / 5 (1) Jul 08, 2018
@ZoeBell.
For example Shell supports "renewables" the most. It realized, that wind plants require so much fossil fuels for their production, that its fossil fuel industry is not threatened the least. Not accidentally the electricity is most expensive just in countries which utilize renewables the most.
Your intelligence is apparently not proof against 'blind-spot' caused selective-analysis/conclusions.

Consider (again):

- the wind plants can then be recycled (so initial/whole-of-life fossil related 'inputs' are nowhere near what a simplistic analysis/conclusion like your just 'parroted' from blatantly FLAWED 'analyses' by simplistically ERRONEOUS 'studies/sources');

- up-front 'price' is more than off-set by 'savings' to health, economic, safety etc budgets;

- not to mention reducing infrastructure/agriculture damage/loses AND reducing Insurance Premium costs 'burden' on ongoing sustainability/affordability etc (which would increase if AGW continues unabated).
TrollBane
not rated yet Jul 08, 2018
"I know you are a very intelligent person, ZoeBell/Zephir" Cleverness can sometimes make for more beguiling self-deception.
TrollBane
not rated yet Jul 08, 2018
"Preventing disasters, such as excessive global warming etc, isn't a product but it is still highly desirable and beneficial so, why not?" You're responding to someone so ideological fixed that they can't conceive of harm reduction and risk mitigation as valuable services.
granville583762
5 / 5 (1) Jul 09, 2018
Lest we forget RealityCheck!
Busy squirreling, tails in the air sequestering "so it's not just us Ostriches that are dim, humans are so intelligent they outwit us!
@ZoeBell.

RealityCheck> Your intelligence is apparently not proof against 'blind-spot' caused selective-analysis/conclusions.

When our tiny minds get out of the sequestering rut, plant life over the billions of years have already sequestered the bulk of the Earth's CO2 already
If there is a moral dilemma, approach it in a sensible manner which unfortunately now a days, this means ignoring current science and applying down to earth common sense!

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