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Old 04-26-07, 12:01 PM   #1
donrhummy
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First Successful Demonstration of Carbon Dioxide Air Capture Technology Achieved

http://www.physorg.com/news96732819.html

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Global Research Technologies, LLC (GRT), a technology research and development company, and Klaus Lackner from Columbia University have achieved the successful demonstration of a bold new technology to capture carbon from the air. The "air extraction" prototype has successfully demonstrated that indeed carbon dioxide (CO2) can be captured from the atmosphere. This is GRT’s first step toward a commercially viable air capture device.
...

The GRT’s demonstration could have far-reaching consequences for the battle to reduce greenhouse gas levels. Unlike other techniques, such as carbon capture and storage from power plants, air extraction would allow reductions to take place irrespective of where carbon emissions occur, enabling active management of global atmospheric carbon dioxide levels. The technology shows, for the first time, that carbon dioxide emissions from vehicles on the streets of Bangkok could be removed from the atmosphere by devices located in Iceland. This could present a solution to three problems that until now have posed intractable obstacles for advocates of greenhouse gas reduction: how to deal with the millions of vehicles that together represent over 20 percent of global CO2 emissions, how to manage the emissions from existing infrastructure, and how to connect the sources of carbon to the sites of carbon disposal.
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Old 04-26-07, 12:19 PM   #2
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Originally Posted by donrhummy
I think nature beat the good scientists with a superior product, many years ago, and these are solar powered, they are called TREES!
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Old 04-26-07, 12:44 PM   #3
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Originally Posted by Wogsterca
I think nature beat the good scientists with a superior product, many years ago, and these are solar powered, they are called TREES!
yes. the experiment in the article just reinvents the wheel so to speak.

also mad tonnes of co2 are sequestered in the ocean.
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Old 04-26-07, 12:53 PM   #4
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Originally Posted by goldener
also mad tonnes of co2 are sequestered in the ocean.
If global warming is a problem, the co2 in the ocean is a good thing, because it's not in the atmosphere.
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Old 04-26-07, 01:03 PM   #5
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If global warming is a problem, the co2 in the ocean is a good thing, because it's not in the atmosphere.
Not really. Burning Fossil Fuels Acidifies Oceans, Erodes Coral Reefs
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Old 04-26-07, 01:07 PM   #6
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If global warming is a problem, the co2 in the ocean is a good thing, because it's not in the atmosphere.
that was my point. sequestration is a natural process, and a good thing, global warming or not.

co2 in the ocean helps stablise climate, and has existed in the ocean prior to any fossil fuels were ever burned.
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Old 04-26-07, 01:27 PM   #7
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The problem here is that we are pumping more CO2 into the atmosphere than would be there through natural processes. Sequestration of CO2 happens naturally, but we have, and continue to throw natural cycles out of balance with our ever increasing volume of CO2. We have added more C02 than the ocean can handle.

We don't even fully understand how the ocean sequesters CO2: Ocean's 'Twilight Zone' Plays Important Role In Climate Change

Science Daily — A major study has shed new light on the dim layer of the ocean called the "twilight zone"--where mysterious processes affect the ocean's ability to absorb and store carbon dioxide accumulating in our atmosphere.

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Old 04-26-07, 02:14 PM   #8
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Step back and consider how desperate people are getting in their attempt to keep fossil fuel culture going at any cost. Sure, we can continue burning all the fuel we want, if only we can get someone else to magically unburn it for us.
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Old 04-26-07, 08:38 PM   #9
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If global warming is a problem, the co2 in the ocean is a good thing, because it's not in the atmosphere.
Nope, it's killing the coral life. And the problem with that? It's the bottom of the food chain and essential to ALL sea life. They're finding that thousands of sea species are dying out where coral is oversaturated with CO2 (which kills the coral and causes it to break apart). It's bad. Very bad.

The good thing about removing CO2 from the air? It'll actually remove it from the water too. They've found that where the water and air meet, they actually are continually exchanging gases in a sort of "equilibrium exercise." So if we lower the CO2 content in the air, the ocean will start to release some of its CO2 (which of course shows just how long this is going to take).
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Old 04-26-07, 09:12 PM   #10
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Originally Posted by goldener
also mad tonnes of co2 are sequestered in the ocean.
This is another reason to lower, or at least stabilize, CO2 emissions as rapidly as possible. As the oceans absorb more and more CO2, which they do very efficiently, the water becomes more acidic. As we speak, in the north Pacific, crustaceans' shells are dissolving. Even more scary is the prospect of a sudden massive decrease in numbers of phytoplankton, which are the basis of the ocean's food web, not to mention the source of most of the planet's oxygen.

I think this carbon-capture technology is a very encouraging development. It's not a permanent fix- we can't just pump CO2 undersground forever- but it might buy us much needed time to get our house in order.

BTW, I agree that trees are a good CO2 absorber (until they die and decompose); we should help third-world countries plant millions of them, and plant a whole bunch ourselves.
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Old 04-26-07, 09:29 PM   #11
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Originally Posted by Platy
Step back and consider how desperate people are getting in their attempt to keep fossil fuel culture going at any cost. Sure, we can continue burning all the fuel we want, if only we can get someone else to magically unburn it for us.
I think most reasonable, well-informed people agree that we'll all need to change the way we do things, if we want to maintain a life that's worth living, and that we'll have to make said changes on a scale of a mere decade or two. But six billion people have a lot of inertia; getting all those people to change course is going to be a gradual process, and probably an extremely painful one even in the best-case scenario. Data that demonstrates that we can extract at least some CO2 directly from the air should come as very welcome news. (I only hope it turns out to be true.) It gives us some much-needed wiggle room. I don't think anyone, including the developers of this technology, think it means we can now sell every Chinese family an Escalade.
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Old 04-26-07, 09:32 PM   #12
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wont be a technological fix that deals with our social problem
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Old 04-26-07, 09:37 PM   #13
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Originally Posted by Wogsterca
I think nature beat the good scientists with a superior product, many years ago, and these are solar powered, they are called TREES!
Guess how much foliage we would need to deal w/ the carbon dioxide current sinks can't take care of.

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BTW, I agree that trees are a good CO2 absorber (until they die and decompose); we should help third-world countries plant millions of them, and plant a whole bunch ourselves.
When those trees mature, they may be a small but viable carbon sink. But until that happens, and especially when they're planted, guess what the influx of cash will do in a fossil fuel based civilization...
That's why, aside from some silly celebrity publicity stunt, we won't see anything about using mass plantings as carbon dioxide sinks.
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Old 04-26-07, 10:15 PM   #14
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Originally Posted by lyeinyoureye
Guess how much foliage we would need to deal w/ the carbon dioxide current sinks can't take care of.



When those trees mature, they may be a small but viable carbon sink. But until that happens, and especially when they're planted, guess what the influx of cash will do in a fossil fuel based civilization...
That's why, aside from some silly celebrity publicity stunt, we won't see anything about using mass plantings as carbon dioxide sinks.
What influx of cash? You think planting a bunch of trees in Chad is suddenly going to make everyone there wealthy enough to go out and build a coal-fired power plant?

And let's consider the benefits of trees besides their usefulness as (temporary) carbon sinks. They prevent erosion. They help local economies. They provide cooling shade, which prevents soil from drying out and absorbing even more solar radiation. In some cases, they even promote rainfall. (Areas of the Amazon rain forest in northeastern Brazil that were totally cut down have since become near-deserts.) It's a pet hypothesis of mine, largely unproved, that worldwide deforestation has done as much to promote global warming as CO2. I think planting a lot of trees is always a good idea. Such a course of action wouldn't solve the warming probelm, of course, but it certainly wouldn't be useless.
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Old 04-26-07, 10:57 PM   #15
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You're right that it wouldn't solve the problem and that it wouldn't be useless. Otoh, it may make the problem significantly worse during the short term, which is especially dangerous due to the potential for positive feedback loops. Here in the US, forests/trees only account for ~12% of all carbon dioxide absorbed, and that percentage is probably similar give or take ~5-10% depending on location. Most carbon dioxide is absorbed by other land biota. And, most carbon dioxide released is done so by the destruction of land biota. Now, just to get this out in the open, stopping deforestation would be great, and probably reduce our carbon dioxide emissions by ~30% alone. Otoh, it isn't the greatest idea to destroy large tracts of vegetation, releasing co2, for some sort of inefficient use like raising cattle for beef, releasing co2, then replant it, with just trees, releasing more co2, infusing local economies with cash, that will spur activity, which will result in more co2 released. Not to mention the trees will take years, if not decades to mature as a co2 sink.

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n the United States in 2004 (the most recent year for which EPA statistics[2] are available), forests sequestered 10.6% (637 teragrams[3]) of the carbon dioxide released in the United States by the combustion of fossil fuels (coal, oil and natural gas; 5988 teragrams[4]). Urban trees sequestered another 1.5% (88 teragrams[5]). To further reduce U.S. carbon dioxide emissions by 7%, as stipulated by the Kyoto Protocol, would require the planting of "an area the size of Texas [8% of the area of Brazil] every 30 years",
Or, conversely, we could simply increase CAFE to ~40mpg, where European countries like France already are. Planting trees in areas where entire ecosystems were destroyed is nothing more than greenwashing imo. Especially considering there are steps that can definitely reduce carbon dioxide emissions by much more, and are much easier to implement. I'd rather not have BP preying on consumer guilt in order to pay for the externalities of their own product, which should have been incorporated into the cost in the first place.

P.s. Deforestation is responsible for ~2 Gt of co2 per year, while fossil fuels are responsible for ~5 Gt of co2 per year.
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Old 04-27-07, 06:50 AM   #16
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...I don't think anyone, including the developers of this technology, think it means we can now sell every Chinese family an Escalade.
But that's pretty much what the article says!

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...The technology shows, for the first time, that carbon dioxide emissions from vehicles on the streets of Bangkok could be removed from the atmosphere by devices located in Iceland....For example, the CO2 originating from all those vehicles in Bangkok can be captured in an oil field in Alberta, Canada, where it could be used on-site for enhanced oil recovery (EOR) operations or it could be captured in South Africa to feed a growing demand in that country for feed stocks for petrochemical production...
To a certain extent I agree that people need to be looking at stuff like this. My objection is to the media spin, which without exception has the subtext of "Go back to sleep, our finest scientists already have solutions to the CO2 problem."
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Old 04-27-07, 08:56 AM   #17
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Originally Posted by bragi
This is another reason to lower, or at least stabilize, CO2 emissions as rapidly as possible. As the oceans absorb more and more CO2, which they do very efficiently, the water becomes more acidic. As we speak, in the north Pacific, crustaceans' shells are dissolving. Even more scary is the prospect of a sudden massive decrease in numbers of phytoplankton, which are the basis of the ocean's food web, not to mention the source of most of the planet's oxygen.

I think this carbon-capture technology is a very encouraging development. It's not a permanent fix- we can't just pump CO2 undersground forever- but it might buy us much needed time to get our house in order.

BTW, I agree that trees are a good CO2 absorber (until they die and decompose); we should help third-world countries plant millions of them, and plant a whole bunch ourselves.
The problem for trees, is that we are deforesting the planet, at one time, most of North and South America were forest, now North America is almost completely deforested, and South America is catching up fast, so at the same time we are pumping CO2 into the air, we are removing the best way to get rid of it, and most of those trees are considered not economically viable, they just pile them up and burn them.
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Old 04-27-07, 11:19 AM   #18
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I really need help to understand this whole process of plants "removing" CO2 from the atmosphere. So here's a question for the science whizzes:

How do plants "get rid of" Carbon dioxide?

My understanding is that in photosynthesis plants use solar energy to take CO2 from the atmosphere, combine it chemically with hydrogen and oxygen (from water) and form carbohydrates, which are the tissues of the plant. In this process, they clearly do remove CO2 from the atmosphere.

So far so good. But what happens after the plant dies? It seems like there are 3 options, and each will release the CO2 back into the atmosphere. Here are the options, as I understand it:
  1. The dead plant is burned in a fire and the carbohydrates are broken down through combustion into water vapor and also emitted as CO2 gas.
  2. The plants rot or decompose, in which case microorganisms, through respiration, break down the carbohydrates and, as a waste product, emit CO2 gas.
  3. An animal eats the plant and through digestion and respiration, breaks the carbohydrates down to provide itself with energy and heat, and in the process emits CO2 gasas a waste product.

If I'm understanding this correctly, the plant only sequesters CO2 during the short period of its lifespan. In fact, even while it's alive, the plant respires and therefore emits CO2.

So how the hell can we say that plants remove CO2 from the atmosphere, at least in any significant way? It seems to me that CO2 is actually being emitted at every stage of the plant's existence, either before or after death.
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Old 04-27-07, 11:32 AM   #19
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This technological removal of CO2 from the atmosphere obviously requires a great deal of study and thought. The last thing we want to do is mess up the atmosphere even more by monkeying around with it. However, I go against the sentiments expressed here. IF these experiments lead to a safe and controllable technology that can undo some of the atmospheric harm we've already done, then I'm all for it.

I don't see any natural fix to the excess atmospheric CO2. The oceans can only absorb so much CO2, and as others have mentioned, at great cost to the chain of life in the oceans. (Not only coral would be affected, but all marine life that requires calcium to make shells.) And unless somebody can answer the question I asked in my last post, I don't see reforestation as the solution either.

Carbon capture at the source will reduce emissions, at a cost of probably only about $35 to $100 per ton of carbon captured (or is it CO2?--important distinction). And of course conservation is the crucial step that we will have to take. Nothing else will work if we don't start reducing use in the first place. But conservation and capture can only take care of future emissions. They do nothing about reducing the current and near-future levels of CO2 in the atmosphere.

That seems to leave only atmospheric removal technology as a solution to the immediate problem of too high levels of CO2. Obviously, however, I would never advocate that we use this technology as carte blanche to burn as much fossil fuel as we want.
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Old 04-27-07, 11:46 AM   #20
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Quote:
Originally Posted by Roody
I really need help to understand this whole process of plants "removing" CO2 from the atmosphere. So here's a question for the science whizzes:

How do plants "get rid of" Carbon dioxide?

My understanding is that in photosynthesis plants use solar energy to take CO2 from the atmosphere, combine it chemically with hydrogen and oxygen (from water) and form carbohydrates, which are the tissues of the plant. In this process, they clearly do remove CO2 from the atmosphere.

So far so good. But what happens after the plant dies? It seems like there are 3 options, and each will release the CO2 back into the atmosphere. Here are the options, as I understand it:
  1. The dead plant is burned in a fire and the carbohydrates are broken down through combustion into water vapor and also emitted as CO2 gas.
  2. The plants rot or decompose, in which case microorganisms, through respiration, break down the carbohydrates and, as a waste product, emit CO2 gas.
  3. An animal eats the plant and through digestion and respiration, breaks the carbohydrates down to provide itself with energy and heat, and in the process emits CO2 gasas a waste product.

If I'm understanding this correctly, the plant only sequesters CO2 during the short period of its lifespan. In fact, even while it's alive, the plant respires and therefore emits CO2.

So how the hell can we say that plants remove CO2 from the atmosphere, at least in any significant way? It seems to me that CO2 is actually being emitted at every stage of the plant's existence, either before or after death.
Hey Roody, in two ways.
1) The way fossil fuels, coal, peat and oil were formed in the first place. They die into an environment where they don't release their carbon to the atmosphere.

2) By creating an environment with a semi- permenant supply of standing biomass. Compare a rainforest with some mono culture replacement. I learned
that many rainforests with their spectacular biomass have very poor soils, when something dies it is quickly recycled into some other living thing. If we reforest areas that have been dunuded the growing trees will remove carbon from the atmosphere. If we manage the forest for wood products in a sustainable way then the living biomass in the forest at any one time will be more than the
biomass from a cattle ranch or sugar cane field.

Maybe if we use #1 on an industrial scale by creating artificial peat bogs that will turn to coal or oil for future generations we can grow a fossil fuel economy with artificial fossil fuels. At any one point in time a huge amount of dead biomass may be in these artificial peat bogs and we use a fraction each year, like a giant
compost heap. It might be doable if we give up on car culture that uses fossil fuel much faster than it is being created.
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Old 04-27-07, 11:51 AM   #21
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But gwd, are you saying that rain forests tie up more CO2 than they emit through decomposition and natural burning? Do they actually remove some of the CO2 that's emitted from the coal generator down the street from me? If so, how much? And has this been proven?

Is the earth still in the process of creating oil and coal deposits? Where and how much?
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Old 04-27-07, 12:53 PM   #22
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Quote:
Originally Posted by Roody
I really need help to understand this whole process of plants "removing" CO2 from the atmosphere. So here's a question for the science whizzes:

How do plants "get rid of" Carbon dioxide?

My understanding is that in photosynthesis plants use solar energy to take CO2 from the atmosphere, combine it chemically with hydrogen and oxygen (from water) and form carbohydrates, which are the tissues of the plant. In this process, they clearly do remove CO2 from the atmosphere.

So far so good. But what happens after the plant dies? It seems like there are 3 options, and each will release the CO2 back into the atmosphere. Here are the options, as I understand it:
  1. The dead plant is burned in a fire and the carbohydrates are broken down through combustion into water vapor and also emitted as CO2 gas.
  2. The plants rot or decompose, in which case microorganisms, through respiration, break down the carbohydrates and, as a waste product, emit CO2 gas.
  3. An animal eats the plant and through digestion and respiration, breaks the carbohydrates down to provide itself with energy and heat, and in the process emits CO2 gasas a waste product.

If I'm understanding this correctly, the plant only sequesters CO2 during the short period of its lifespan. In fact, even while it's alive, the plant respires and therefore emits CO2.

So how the hell can we say that plants remove CO2 from the atmosphere, at least in any significant way? It seems to me that CO2 is actually being emitted at every stage of the plant's existence, either before or after death.
Plant's don't emit CO2 during their lifespan, what they do, is you take two chemicals the plant needs CO2 and H2O, it chains the hydrogen, carbon and 2 of the oxygen atoms together to make a carbohydrate, the third oxygen atom isn't needed, and is released by the plant. Carbon is a basic cell building block, so for large plants, the carbon is sequestered (held) within the plant, there is a lot of carbon in a California Redwood. When the plant dies, some of the plant material is eaten by various forms of animals, who do release some CO2, some of that carbon ends up in the soil as well, where it stays sequestered. As long as it's not combined with Oxygen, it stays as Carbon, it doesn't revert to CO2 right away.
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Old 04-27-07, 01:35 PM   #23
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But gwd, are you saying that rain forests tie up more CO2 than they emit through decomposition and natural burning? Do they actually remove some of the CO2 that's emitted from the coal generator down the street from me? If so, how much? And has this been proven?

Is the earth still in the process of creating oil and coal deposits? Where and how much?
Yes, as rainforests grow they tie up more than they omit, as their biomass increases. At some point they reach a steady state of course. As far as "proven" it seems obvious as the mass increases the amount of carbon removed from the air increases. Gases diffuse at amazingly high velocities, according to my chemistry professor so probably some small number of CO2 molecules from that coal plant down the street would be captured by a growing forest.

I don't know how much but when mudslides cover forests or earthquakes cause forests to subside below the water table the carbon gets trapped right? If we hadn't drained the everglades the peat in florida would continue to trap carbon.
I just read a book on archealogical discoveries in peat in Florida. If developers hadn't drained the lake the organic deposits would have continued to grow there. So yes the conditions for fossil fuel formation still occur. I was suggesting that we encourage those processes as a way to capture carbon for future generations to use at a slower rate than we use it. Maybe we can speed the formation process by encouraging the right conditions? Extending wetlands would help.

As it relates to car free living if we depave suburbia and let the paved areas revert to forest we can increase the amount of carbon stored in the biomass that replaces the concrete. Again the carbon will cease accumulating when the forest reaches a steady state. If we build with less concrete and more wood the wood stores carbon for 100 years or so.
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Old 04-27-07, 06:25 PM   #24
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An atmospheric carbon sequestration scheme that appeals to me is to (1) grow trees, (2) harvest the wood as biomass, (3) convert to charcoal through partial oxidation, yielding (4) some energy and (5) pulverized charcoal for topsoil amendments. There is some reason to think adding charcoal to the soil improves it greatly for agriculture (google terra preta soils), plus the carbon in that form could remain sequestered for thousands of years. One problem is that agriculture with terra preta soil isn't completely understood right now, it's a pre-columbian technology that has to be re-discovered.

No way does that let everyone in China drive an Escalade, though.
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Old 04-27-07, 11:20 PM   #25
cerewa
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Sure, we can continue burning all the fuel we want, if only we can get someone else to magically unburn it for us.
When you put it in those words, it certainly sounds similar to a "faith healer" scam, pyramid scheme scam, or whatever.

One of the problems I had with the original article is that it doesn't seem to touch on how the carbon is "caught", what form it will be in when caught, and where it will go after that. It doesn't explain how the system might be better than or different from just growing plants and leaving them somewhere where they will not, for the most part, rot or be eaten. (Which doesn't sound like such a great idea to me.)

Last edited by cerewa; 04-27-07 at 11:29 PM.
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