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Goodbye Global Warming!...Hello Terraforming?
silance writes "Here is an article from Science Daily detailing a new method for extracting carbon dioxide from the atmosphere on a large scale and at normal concentrations. Previous systems require placement near high concentration centers such as power plants, and do not address low-concentration sources (such as internal combustion engines) which are responsible for half of the world's carbon dioxide pollution. The article descibes the technology as scalable to the point of repairing Earth's atmosphere to pre-Industrial-Age levels! Next stop, Mars..." I seem to remember something like this in SimEarth ? - but I'm not going to hold my breath (Ha! I pun!) waiting for this.
When did trees go out of fashion?
Why invest so much money trying to replicate what just about all plants do naturally? I mean, geez, perhaps we will surpass plants' abilities to process Carbon Dioxide, but do you think it will run on water, Carbon Dioxide & dirt?
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
It would make it easier to get funding.
As a chemist I can say that the idea of capturing CO2 with CaO on an industrial scale is extremely optimistic.
It will consume huge amounts of energy to convert back and the efficiency will be very low. The figures come out so optimistic only if you forget about the fact that CaO gets covered by Ca carbonate quickly and in the absence of water the diffusion of CO2 to the remaining CaO will slow to a crawl.
Only alternative to this is to disperse the CaO to micron sizes which means emitting insane amounts of dust into the atmosphere. Same is valid for extracting back. Unless you make the CaCO3 granules of micron or less size the energy efficiency in recovering CaO is very low.In either case you either need huge amounts of water or you will pepper with CaCO3 dust everything several thousands miles windward.
This reeks of "reaserch" sponsored by specific global warming villains. Just the mentioning of "there is enough fossil fuels" about says it all. No names mentioned... We know them all...
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
For 20 cents per gallon, you could subsidise a better fuel such as Biodiesel which absorbs more carbon while growing than it emits while being used as fuel.
Also you could plant a lot of trees!!
Imagine No Restrictions On Fossil-Fuel Usage And No Global Warming
I kind of found this headline a bit disturbing... I hate things like this because they really discourage any responsibilty... It reminds me of all those miracle diets; "Eat all the fatty foods you want and don't gain a pound." Seems like people today just don't want responsibility.
I'm sure it would be a lot better on the planet on a whole if we aimed to reduce emmisions gradually, thus *if* there were any consequences to the environemnt they could probably be dealt with a lot easier than massive forest die-offs or the like.
Of course reducing emissions need some sort of united effort *cough* kyoto *cough*...
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Some weasel took the cork out of my lunch.
Lets take the chemistry a bit further...
Converting the CaCO3 back into CaO will take a minimum of 176kJ/mol CaCO3. (CaCO3 + 176kJ -> CaO + CO2). Not even getting into thermodynamics, it will actually take more energy than that - since it can't be done in anything other than a CO2 atmosphere (since they want to recover the CO2).
But for sake of argument, we will use the 176kJ figure. Now, it will take an enormous amount of HEAT to to release the CO2. How are we going to create this heat? How about fossil fuels!
Let's say we use gasoline to heat the CaCO3 and recover the CO2. Gasoline is nearly the hotest burning fossil fuel. Oxidation(burning) of gasoline follows 2C8H12 + 25O2 -> 16CO2 + 18H2O + 5249kJ.
Wow that's hot! Problem though - we just released 16CO2's in that reaction! No problem, we'll just scrub them out with all the rest of CO2 in the atmosphere (notice this machine is getting more and more complicated as we speak).
The energy required to suck that CO2 that we just produced back into a bottle is going to cost us 2816kJ. Which leaves us with 2433kJ to extract more CO2. Unfortunately, the world isn't perfect and we are assuming 100% efficiency.
What does that mean in the real world you ask? Well, given a 100% efficient blackbox into which we feed gasoline and air:
To extract 1 ton of CO2, we will use about 1/4 ton of gasoline (.255ton), almost a ton of O2 (.894ton), and will produce nearly a half ton of H2O (.402ton).
So for all our time and effort, we just created a larger demand for fossil fuels for a process which not only removes CO2 from the atmosphere, but also a NEARLY EQUAL AMOUNT OF OXYGEN!!!
It appears Ockham lost his razor and grew a beard.
Hi!
Okay--one square yard equals 9 square feet. There are 43,560 square feet in an acre, so 1 acre worth of quicklime would recapture CO2 for 4,840 people. There are, as of April 1, 2000, 281,421,906 people in the United States. So we'd need 58,145 acres of quicklime to process CO2 for just the United States.
Quiz: How big is Rhode Island?
Let's just skip the obligatory comparison to the size of the state of Rhode Island--and concede that we're talking about a lot of land. And, oh yeah--we're also talking about a huge amount of quicklime. Which will, of course, need to be replenished all over those tens of thousands of acres. And building a collection system to capture the calcium carbonate from all those tens of thousands of acres wouldn't be child's play, either. And then it has to be processed, and so forth.
This is the kind of government proposal that used to give the Keynesian macro-economics professors a head rush. Just think of the economic multipliers--think of all the jobs created finding and surveying and buying some 60,000 acres of land. Think of all the money spent on massive construction equipment necessary to find, dig, and move 60,000 acres worth of quicklime. Think of all the steel involved in building the equipment necessary to collect all that calcium carbonate. Think of all the steel, electricity, and machinery that will be required to do all this processing. Think of the tens of thousands of jobs we're talking about. Whoopie!
And, oh yeah! Think about the amount of CO2 generated by the electricity used to produce all that steel; and all the CO2 generated by all those cars driven by all those employees, and all those earth-movers scraping depleted quicklime out, and pushing new quicklime back in.
Still with me? Now consider this: there aren't a lot of vacant 60,000 acre tracts of land available in the Washington, D.C. metro area. So a project of this magnitude would require moving all those tens of thousands of people to wherever this (by definition) arid wasteland would be.
This isn't simple, and almost certainly not feasible
Okay, I'm just a simple programmer and part-time college professor. What could I possibly know? It seems pretty clear to me that this announcement wasn't peer-reviewed, or if it was, the peer-review processing happened at a really good office party. The chemistry might be "simple," but the project would not be.
Maybe I'm just turning into a conspiracy theorist, but this looks like it's trying to get people to waste more fuel, and possibly support drilling in more places, such as the oft-contested ANWR.
I don't understand why the US government seems to be so intent on getting people to continue using lots of energy (/me says as he sits in an air-conditioned apartment with numerous computers running constantly..). Okay, I do know -- damn near everyone in the administration came from an oil company. Bush, Cheney, hell, even Condoleeza Rice..
Anyway.. Conserving just a little here and there can do quite a bit, especially since folks here in the US already use the most energy per capita.
I agree with the other comments. Plant a tree (or ten, or a hundred..) Get a slightly smaller car, or at least one with a better engine/transmission. Support biodiesel or other renewable energy sources.
Also, the article doesn't appear to say you can make fuel out of the carbon dioxide -- they just found another way to get a supply for people who already use it (the big one being oil refineries).. So, okay, it allows you to re-use CO2 that gets into the air, rather than just leaving it there. Still, I think trees are probably more efficient at it than this idea (an unscientific quick glance at it, unfortunately).
Somehow, this article just seems to be misplaced optimism..
60,000 acres is the size of a moderate wheat ranch in Montana. It's a tiny fraction of the size of the US, and it doesn't have to be centralized. We're talking about facilities comparable in size and complexity to sewage treatment plants, on a per-capita basis. If we can build power plants and the infrastructure to support them, we can certainly build these.
As for the industrial side of getting all that quicklime, that's not a huge endeavor compared to any other kind of mining. We pull so much copper and bauxite and titanium and coal out of the earth that extracting a few million tons of quicklime wouldn't change the scale of the world's mining industry perceptibly.
Would it work? Maybe, maybe not. BUT, the argument against it on size and complexity does not appear valid.
-- Jeff Paulsen