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DoE Considers Artificial Trees To Remove CO2
eldavojohn writes "CNN is running an article on a new angle of attack to reducing greenhouse gases. After meeting with the US Department of Energy on the concept, the researchers revealed the details that each 'tree' (really a small building structure in the concept design) would cost about as much as a Toyota and remove 1 ton of CO2 from the air per day. Don't worry, they're accounting for the energy the 'tree' uses to operate: 'By the time we make liquid C02 we have spent approximately 50 kilojoules [of electricity] per mole of C02. Compare that to the average power plant in the US, which produces one mole of C02 with every 230 kilojoules of electricity. In other words, if we simply plugged our device in to the power grid to satisfy its energy needs, for every roughly 1,000 kilograms [of carbon dioxide] we collected we would re-emit 200, so 800 we can chalk up as having been successful.' Each unit would remove 20 automobiles' worth of CO2 from the air and cost about as much as a Toyota... so the plan might be a five percent surcharge on automobiles to fund these synthetic tree farms."
Umm, injecting CO2 into oil wells to enhance recovery has been used for some time, limited primarily by supplies of CO2. Injection into empty gas wells is doable as well, and somewhat more exotic approaches(like bubbling the stuff through algae farms) aren't too far outside the realm of the currently possible.
As for CFLs, Recyclers aren't too hard to find. (More generally, mercury containing florescent lamps(mostly the conventional long-tube type) have been used in commercial and industrial applications for decades; because they are cheap and last a long time. Somehow, nobody worried at all about that, until they became associated with the evil environmental movement, at which point their mercury content became a talking point. Funny how that works...)
As an experienced scientist, placing any form or CO2 in water is a very bad idea. Eventually it will change states from solid to gas or from solid to dissolved in water, which then is known as carbonic acid. This is exactly how your body deals with CO2, it is dissolved in your salty blood, where it is expelled as a gas from the lungs. Only hemoglobin transports oxygen to the tissues, it does not transport CO2 in any way shape or form. CO2 will influence the affinity oxygen has for hemoglobin, and in the presence of higher concentrations of carbonic acid, hemoglobin more readily releases oxygen to the surrounding tissues. Hemoglobin will also transport CO, carbon monoxide, but the binding is through carbon-metal (iron) back bonding, not through the oxygen. I didn't even mention the unknown effects this would have on marine life.
The only way to curb CO2 in the atmosphere is to stop burning fuel and let natural vegetation grow. This also means letting forests GROW and not clear cutting for land development, wood, and paper.
I don't know where to begin.
Do you know how many species of trees are native to the more arid parts of California? The problem with most of Los Angeles, is exactly what you propose. A decades-long successful but misguided effort to cut down trees in order to save a few dollars in maintenance costs. Dunno about you, but the endless miles sun-bleached concrete and asphalt is hardly a hospitable environment, to say nothing of the problem with everyone needing an airconditioner to get through the summer because no one's thought to actually plant a frigging tree.
Seriously, you have a problem with trees? I'd suggest that if everyone started planting new ones and did so for the next decade, we (and our planet) would be better off.
Can't we turn it into biodiesel with algae farms? That would be win-win.
Or, build a glasshouse near your power plant. Pipe the CO2 from the power plant into the glasshouse. In winter (and summer, if needed) heat the glasshouse using waste hot water from the power plant. Grow tomatoes.
This is already done in lots of places.
If we could cover all the land area in the world with bamboo (heh) then we could sequester basically all excess carbon in 15 years or less. We can't, but anyway.
There's plants other than trees which are applicable.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Finally, my M.S. on the deep-ocean sequestration of carbon dioxide becomes relevant!
CO2 is a supercritical liquid at depth, denser than water. Here's the stuff at 3300 meters (courtesy of MBARI)
Here's your phase diagram.
Here's some pictures that show CO2 at depth.
Once at depth, the CO2 will slowly dissolve into the seawater, lowering the pH. Of course, we're doing this at the ocean surface as-is, so one can make the argument that it's less bad to acidify the deep ocean slowly vs. surface waters quickly.
If you drop dry ice overboard, a goodly amount of it will dissolve before reaching bottom. There's research on this; I leave finding the reference as an exercise.
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