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Direct Air Capture
9

Direct Air Capture

RE: Direct Air Capture

I wonder how many nuke power plants they'll build ?

none ??

another day in paradise, or is paradise one day closer ?

RE: Direct Air Capture

(OP)
I would imagine 0 nukes. Coal power is the way to go with this option. They provide the coal plant with a nice 24/7 base load and capture their CO2 before it floats off. Everybody wins.

RE: Direct Air Capture

Quote (The article)

...pull carbon from the air and magnetically attach it to calcium or potassium molecules...

Huh. Magnetically.

The problem with sloppy work is that the supply FAR EXCEEDS the demand

RE: Direct Air Capture

The article leaves a lot to be desired; such as any technical details whatsoever as to how this idea would feasibly work.

Somehow have an unlimited and economical supply of calcium and potassium to bond it to? Yeah, ok.....

Just keep pumping that material into the ground for permanent storage? Yeah, ok.....

I said the same thing in another, similar thread some time ago. Unless whoever is doing the "capturing" has a ready use for the captured carbon, it isn't sustainable or feasible. It has to go somewhere and into the ground moves the needle of my BS meter past the redline.

Andrew H.
www.MotoTribology.com

RE: Direct Air Capture

(OP)
Think "magically", if it helps.

SuperSalad,
Supposedy the world would have been determined to not be sustainable if they have to start this plant up and you're worried about what, the plant???

RE: Direct Air Capture

wouldn't it be better to leave to coal in the ground and use cleaner fuels ?

like nukes ?

another day in paradise, or is paradise one day closer ?

RE: Direct Air Capture

(OP)
Let's think about that for a ms or two. Times up. No.

But maybe OK, if you volunteer to bury the spent fuel in your backyard.
Spent fuel; the dirty little secret about nukes.

RE: Direct Air Capture

If someone suggests DAC before going after concentrated sources then they full of $hit.
The catalytic capture approach works well with concentrated sources since there is much lower energy input requirement. Putting this on a NatGas power plant makes sense, there is no S poisoning of the catalyst to worry about.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Direct Air Capture

(OP)
Will it work on atmospheric CO2 concentration levels, or you trying to say it costs too much?
I worked for a company that captured nitrogen, oxygen and argon from the atmosphere, put it in bottles and sold all of it for a profit. We scrubbed out the CO2 first with NaOH so it didn't freeze up in the pipes. I'm sure if we wanted CO2 for something, we could have got our hands on that too. Can you explain why this won't work?


RE: Direct Air Capture

Costs too much.

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P.E. Metallurgy, consulting work welcomed

RE: Direct Air Capture

(OP)
Costs more than burning up the Earth.
How is that possible.
Given the alternative, seems to be cheap at twice the price.

RE: Direct Air Capture

I am working on a project where we are taking an old manufacturing plant that uses NatGas furnaces for process heating. We will duct all of them to a CC unit. That is a feed that is a few thousand ppm CO2 and the operating costs are low (capital is a bit high).
So as long as there are CO2 rick streams out there that should be the target.
Though our set up will allow free air capture when the plant is not operating.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Direct Air Capture

(OP)
Great. Now that is interesting.
Is there an end use for the CO2; something other than underground injection and storage?
CO2 is being pipelined to some oil fields to be used for injection enhanced production.
Can you estimate something like the capital costs per MMCFD capacity and CO2 extracted?

RE: Direct Air Capture

4

Quote (1503-44)

Supposedy the world would have been determined to not be sustainable if they have to start this plant up and you're worried about what, the plant???

I'm going to guess at what your saying here because I can't tell for sure, and please feel free to clarify if I am incorrect.

No, the world is highly sustainable, continued and unchecked human expansion is the unsustainable part of the equation. The solution is not to do more and sweep the dirt under the rug, it is to do less and bring in less dirt.

Quote (1503-44)

Spent fuel; the dirty little secret about nukes.

Maybe in 1960 that statement would be accurate lol. It is no secret.

Demonization of nuclear energy has got to be one of the most successful crowning achievements of the fossil fuel industry.

Andrew H.
www.MotoTribology.com

RE: Direct Air Capture

Today there isn't much else to do with CO2 unless you are a chemical plant and you can blend it into your feedstock. There are proposals for making various fuels or carbonates but as of today these require too much energy input (they need to find better catalysts).
Cost, well we will find out if this gets off of the ground. The estimates are all over the place. But the richer the stream the less house power required to drive the system.
We are doing this as a step to start cleaning up and old existing facility.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Direct Air Capture

"But maybe OK, if you volunteer to bury the spent fuel in your backyard.
Spent fuel; the dirty little secret about nukes."

1) actually I have a reactor close to my backyard (I can see it from my backyard).

2) Only an IDIOT would bury nuclear waste in his backyard.

3) No, nuclear waste is not a "dirty little secret" it is a very well understood issue with nukes, certainly nukes using Uranium. Yes, waste is a huge problem but one that can be solved ... we have short term solutions now, and could develop long term solutions if the need was there. We could develop other nuclear reactor designs that produced less waste.

Coal fired power stations work 'cause the fuel is cheap and plentiful. If you add this complexity to them, they'll probably become uneconomic (I see these plants as making CO2 from coal, then recovering this CO2, with a very small net power. Better to leave the coal where it is, or to liquify or gasify it.

another day in paradise, or is paradise one day closer ?

RE: Direct Air Capture

why not use the bio-capture as a fuel stock ? The issue with FFs is that we're using Carbon that was removed from the atmosphere eons ago (and over eons) and dumping it back into the atmosphere today (and at much quicker rates). Bio-fuels take from the atmosphere yesterday and put back tomorrow ... a more tidal component than a tsunami.

another day in paradise, or is paradise one day closer ?

RE: Direct Air Capture

rb, once someone has a good method for making a fuel or alcohol from algae or similar biomass then feeding the CO2 into growth ponds would make sense. In the Netherland they pump the CO2 into greenhouses to increase growth rates.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Direct Air Capture

The very same thing that makes CO2 a valuable product of energy producing reactions like combustion (low Gibbs free energy), makes it a terrible feedstock for processes to make anything like a FUEL.

Nature does this because it must, and because we're awash in sunlight. And after a billion years of evolution, it's managed to get this to 2% efficiency in terms of joules of carbohydrate energy per joule of light energy incident on the leaves.

As to whether or not direct air capture makes sense:

1) To capture a tonne of CO2 from the atmosphere at 416 ppm, requires moving 1600 tonnes of air, bare minimum, through your absorber. Why would you needlessly do that, when you could instead capture from a cement kiln's calciner output at 400,000 ppm CO2?

2) You patch the hole in the hull before bailing does any good

3) If you have energy over here in excess to run a direct air capture unit, and you are burning fossils over there for energy, the best solution is to connect the two with a WIRE, not with some lugubrious carbon recycler

Direct air capture plus water plus electricity back to fuels is the equivalent of gluing Humpty Dumpty back together again after deliberately throwing him off the thermodynamic wall.

RE: Direct Air Capture

(OP)
What you say makes complete sense. Compounds resulting from combustion have a low remaining energy state and, if your goal is to capture CO2 for economic purposes, that would be much more favourable to do where high concentrations and some symbiotic relationship exist with an adjacent process or end use. IMO the authors are considering that those possibilities have been exhausted, stack cleanup has become the norm and their only purpose is to actually clean up residual atmospheric CO2 at far lower concentrations and without any additional economic benefits from reformulation or recycling the CO2 so captured. Since we are not doing that yet, it is helpful to look at existing stack cleanup projects to try to determine if their actual capital and running costs would be relevant to situations where atmospheric cleaning alone is the primary objective and to investigate other potential uses of CO2 that havent made it into the spotlight so far. Unfortunately there dont seem to be many.

RE: Direct Air Capture

"In the Netherland they pump the CO2 into greenhouses to increase growth rates." True, higher CO2 improves plant growth ... but makes me wonder where they get this CO2 from ? produce by chemical reaction and add to atmosphere, or remove for atmosphere (probably more expensive to do) and return to atmoshpere ?

another day in paradise, or is paradise one day closer ?

RE: Direct Air Capture

MM, agree with you all the way.
In the Netherlands they take the CO2 rich stream from some other process, they don't make it just for this.
There are only a handful of commercial uses of CO2; for well injection, as CO2 for carbonation, as a foaming agent, or as feed to make solid carbinates. It is really just a matter of being able to offset some of the operation expenses.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Direct Air Capture

Quote (1503-44)

Costs more than burning up the Earth.
How is that possible.
Given the alternative, seems to be cheap at twice the price.

One of the things I think we sometimes fail to acknowledge is that there is a difference between KNOWN economic costs and projected / estimated economic costs. Look at it this way, who's the more valuable NFL quarterback, Jimmy Garoppolo (an imperfect, but known commodity) or Trey Lance (a projection of a draft choice based on his college production).

What I mean by this is we can compare costs or efficiency of EXISTING means of energy production relatively easily. Coal power plants cost a certain number of dollars per kilowatt generated and generate a certain amount of CO2 per kilowatt. Compare that with Combined Cycle Gas turbines, nuclear, hydro-electric, wind or solar. This becomes a VERY accurate measure of the relative efficiency of these technology. It's much easier and more reliable to make decisions about penalizing or funding based on this really good quality data.

Now, when we start projecting experimental technologies (like the kind listed in this article), it's a lot more unknown. So, when projections are sky high, I take it as a reflection of the unknown. It might be that high, it might come down. Hard to tell. Either way, I'd think it would be really important to compare the relative cost efficiency to existing technologies for reducing atmospheric carbon.... like planting / re-planting trees, bushes or other such natural means of pulling CO2 out of the atmosphere.

Lastly, the idea of comparing a relatively unknown technology like this method of carbon capture to the even more unknown projected economic cost of a similarly projected rise in temperature seems like comparing unicorns farts to dragon breath. I joke, but the uncertainty of such a comparison is so high it makes the comparison very silly.

RE: Direct Air Capture

To be clear, I think Global Warming is real and that atmospheric CO2 is a major contributor. I just think we should deal with it as a question of energy economic policy rather than treating it as an existential threat to the future of earth or our species.

RE: Direct Air Capture

geeze, people have been (figuratively) stoned for saying less !

another day in paradise, or is paradise one day closer ?

RE: Direct Air Capture

(OP)
"I just think we should deal with it as a question of energy economic policy "

OK. If it doesn't work one way, then hopefully we can make it work in another.
You have some ideas about how to do that as part of energy economic policy?

RE: Direct Air Capture

Quote (1503-44)

You have some ideas about how to do that as part of energy economic policy?

Well, not for removing CO2 from the atmosphere. That's not an aspect of the issue that I've thought about. However, there are a lot of ways to reduce our current production of CO2.

a) Nuclear is largely carbon free and very efficient at energy production. So, expand nuclear energy production.
b) Burning coal is much less efficient (in terms of tons of CO2 per megawatt produced). So, IMMEDIATELY switch over from coal to dramatically more efficient (but still imperfect) means of energy production like combined cycled gas turbines with
c) For "green" methods of energy production, rather than focusing on government funding for rich people to get roof top solar (which are rich people virtue signaling their environmentalism) throw that money towards the type of solar that uses steam turbine generation to produce energy. Essentially reflective mirrors that heat up the water source to create steam and generate turbines. Only in that I think this is a more promising technology though it's only efficient in locations (like the desert) where the sunlight is plentiful and land is cheap.
d) Legislate more MPG restrictions on cars / trucks to force us towards more efficient hybrid technologies. Or, even better steeply increase the tax rates on inefficient cars and throw that money towards discounts towards the most efficient ones.
e) Maybe add steep import levies on foreign generated oil is it comes from locations that don't capture the natural gas that is emitted when drilling for oil (because it's not as cost effective to capture).
f) Levies on imported trade goods that come from countries that use coal to generate their power or which don't have certain types of environmental regulations.

One of the things that we MUST do is address the fact that many of the countries with the worst CO2 production in the world currently benefit from our economic policies. Why? Because all of the environmental regulations that we impose on ourselves in the US (and even more so in Europe) merely result in the manufacture of goods shifting to far away lands that don't have these regulations. Which results in WORSE treatment of the environment and also necessitates the shipment of these goods over very long distances.

RE: Direct Air Capture

(OP)
Thanks. I wasn't sure what energy economic policy was. So its a combined energy use and economic policy.

There's food for thought there.


RE: Direct Air Capture

Sorry, I grew up with that term Energy Economics (my father being the founding member of the International Association of Energy Economics). The idea behind the organization is that the discussion of energy issues at the time tended to be very heated politically, but involved little rational discussion of economics. Since he had a background in Government and Academia (and many contacts there) and had just started working for private industry, he felt like there needed to be a forum for these excellent minds from the various sectors to meet and exchange ideas.

That was true then when when inflation and oil prices was the big issue. I see a lot of similar issues today where CO2 emissions are the big issue. The discussion today (IMO) is mostly dominated by political actors and environmentalists (including climate scientists) helped along by allies in mass media. Unfortunately, there is very little discussion of the economics of energy. Despite the fact that there are lots of good articles published on the subject from various positions.

https://www.iaee.org/en/inside/history.aspx

RE: Direct Air Capture

(OP)
Politics has taken over science, economics, religion and just about everything else.

RE: Direct Air Capture

I tend to agree.... But, it doesn't have to be that way. Not sure how we get away from that nationally. But, we can all do it locally and in our personal interactions.

RE: Direct Air Capture

(OP)
I send my senators semi-regular advice, but it goes in one ear and quickly echos back out. I get better responses from senators I write to in states where I used to live.

RE: Direct Air Capture

"The machines essentially function like giant vacuum fans that pull carbon from the air and magnetically attach it to calcium or potassium molecules, transforming the emissions into a substance that can be injected underground for permanent storage, to prevent its return to the atmosphere."

I worked on this exact subject in graduate school and 2 years into a PhD program (did not finish due to extenuating circumstance) and I say this is not a viable strategy. It's a fun idea, but the sorption levels are not high enough to make a real difference, and mining companies walk a very fine line between business and compliance with environmental regulations. They all but threw us out after our pitch meeting. haha.

Bottom line, it's "feel good" science that would end up being another Solyndra debacle.

It's the exact subject that made me cynical about academic types and their incentive structure. I definitely wrote and edited my fair share of shady money-grab proposals while in school. Tenure can be a perverse master.

RE: Direct Air Capture

Quote:

It's the exact subject that made me cynical about academic types and their incentive structure.

Yup. Similar things are true all around. The politicians push stuff not because they think they'll work, but because it helps them to raise funds for re-election or excites their base. Industry groups are rightly concerned about their own profits and how regulation will affect them.

Every group acts in their own self interests. That's not a bad thing. But, we need to do a better job of balancing the various considerations and taking real and rational action. Actions that are both scientifically and economically feasible.

RE: Direct Air Capture

(OP)
I admit I've done my fair share of laughing off PhD opinions.

RE: Direct Air Capture

I look at the "direct air capture" technology kind of similar to how I look at Santa Barbara's desalinization plant. California is in a constantly cycle of drought / non-drought. So, when we were deep in a drought Santa Barbara built a desalination plant to convert sea water into drinking water.

It's proven technology, but it's also very expensive. The plant was built in 1991 and only operated for 5 months. Then it was de-commissioned until 2017 and now provides about 30% of the cities water supply. It deserves to be in the discussion when we are in crisis mode for water supply. Even having it run like it does now provides us with flexibility in case other things happen.

However, it alone is not a solution. Part of the solution, sure. But, the economics of desalination means that it shouldn't be looked at as a MAJOR solution to our problems.

RE: Direct Air Capture

Oz too. Sydney built a desalination plant in the last drought ... now they're drowning (again).

another day in paradise, or is paradise one day closer ?

RE: Direct Air Capture

(OP)
It seems that they think being prepared is better than insufficient water supply during times of drought. You know what they say, when it rains, it pours. In any case, weather is certainly appearing to be getting extreme, according to your own observations, so it just could be a prudent investment. So, what are you saying? That the droughts are finished and they wasted their money? It would seem that they should look at desal plants or building a large dam. Problem with dams is that if you don't ever get rain again, you don't have any water at all.

RE: Direct Air Capture

Quote:

So, what are you saying? That the droughts are finished and they wasted their money?

Well, the first time that certainly seemed to be the case. The spent a ton of money building the plant then turned around and immediately de-commissioned it.

The current path (of keeping the plant going as a low level so that they are not as vulnerable to drought) makes a lot more sense. It's accepting a higher long term cost to do away with periods of extreme fluctuation.

But, what I was really saying is that the carbon capture technology that was described in the article in the initial post shouldn't be viewed by itself as a true "solution" to the problem of CO2. It can be part of a solution, maybe. But, the economics of it likely prevent it from being a realistic MAJOR player in the solution.

If you ignore the economics of your proposed solution, then you are inefficiently allocating your resources. If you ignore the economics of other partial solutions because they are imperfect and don't check the right political boxes (e.g. nuclear), then you're putting your idealism over practicality and are likely destined to fail.

RE: Direct Air Capture

(OP)
Sorry, I was asking rb1957 what he was going on about.

Future planning is just like trying to cover all the spots on a roulette table with limited resources and the table is getting larger these days. Basically those in charge are forced to make difficult decisions from too many possibilities and will be damn lucky if they get very much right in the end. One thing for sure is that everyone will find fault, because no matter how successful they might be addressing one concern, there are not enough resources (taxes) to cover all bases, so plenty of potential for failure. Apparently people are fine with that approach, keeping tax rates low, right up to the point where failure occurs and they conveniently blame the planners for their lack of foresight.

RE: Direct Air Capture

My point was like Josh's ...
Australia had a very severe drought, water levels were getting very low, so they built a desalination plant. Soon after the rain came and now the plant is idel.

Yes, you (and Josh) are right. There came a future need (in Josh's case, and there will be in Australia's) and so they were ready. Unfortunately I'm sure that in both cases someone made political mileage out of the "waste" (build a plant only to not need it). I'm certain too that people (politicians) will spend tonnes of time talking over whether to keep funding the plant's maintenance (to have it ready if needed) or to mothball it, or to sell it (to someone's crony).

another day in paradise, or is paradise one day closer ?

RE: Direct Air Capture

(OP)
OK, now I understand. Yes, unfortunately the world's supply of crystal balls has always been lacking, especially the ones that work. All we can do is make the charts and see what range of future values look like, then count the money available to see how to best get us there.
As has been quoted many times,
" It's tough to make predictions, especially about the future." ― Yogi Berra.

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