Living Car Free - Removing CO2 from the air...

New group claims to have an efficient way of doing it. The question is: is this an actual solution to the problem or a near-useless red herring?

http://cleantechnica.com/2008/09/29/scientists-create-device-to-remove-carbon-directly-from-the-air/

Scientists from the University of Calgary in Canada have created a method to efficiently capture carbon dioxide directly from the air around us. The device, which is built on near-commercial technology, was built by Uof C climate change scientists David Keith and his team.


In a recent test, Keith and his team demonstrated that they could capture CO2 directly from the air, using less than 100 kilowatt-hours of electricity, and capture the equivalent of about 20 tons per year of CO2 on a single square meter of scrubbing material. “This means that if you used electricity from a coal-fired power plant, for every unit of electricity you used to operate the capture machine, you’d be capturing 10 times as much CO2 as the power plant emitted making that much electricity,” Keith says.

We already had this. It's called a tree... although we seem hell-bent on cutting them all down.

The idea of storing CO2 away seems like a REALLY bad idea. Haven't we proven that time and time again with the various crap we've tried to bury in the past?

I mostly think of Lake Nyos, which had a bunch of CO2 stored underwater that outgassed all the sudden and suffocated a huge area when I think of CO2 storage. At least nuclear waste is fairly compact.

If we'd stop adding carbon into the atmosphere, the solution would be fairly simple... stop recycling paper and composting veg waste and start burying it in landfills.

We already had this. It's called a tree... although we seem hell-bent on cutting them all down.


These things are actually pretty good at sucking CO2 out of the atmosphere. There was an article in the New York Times about a study of tree growth in locations with different levels of CO2. Apparently, in many cities, the levels are quite a bit higher than in nearby countryside. As you might expect, the study discovered that these trees grew at a much faster rate than their country cousins.

article (http://www.nytimes.com/2008/06/29/magazine/29weeds-t.html)



By comparing three sites — an organic farm in western Maryland, a park in a Baltimore suburb and the one by the inner harbor — Ziska planned to study three circumstances: the present (on the organic farm), the mid-century future as predicted by the climate-change panel (in Baltimore) and something in between (the suburban site). He took soil from the organic farm, which already contained seeds of 35 common weeds, and with it created uniform beds at each of the sites, urban, suburban and rural, so that the growing medium and weed population would be the same throughout. What happened over the next five growing seasons surprised even him.

Not only did the weeds grow much larger in hotter, CO2-enriched plots — a weed called lambs-quarters, or Chenopodium album, grew to an impressive 6 to 8 feet on the farm but to a frightening 10 to 12 feet in the city — but the urban, futuristic weeds also produced more pollen. Even more alarming was the way that the increased heat and CO2 accelerated and perverted the succession of species within the plots. Typically, a cleared area in the Eastern United States, if left to itself, returns to native woodland. This process varies with the site and circumstances, but in its archetypical form fast-growing annual weeds cover the soil first, playing the role of what ecologists classify as “pioneer plants.” These gradually give way to longer-lived perennial weeds, which are in turn replaced by shrubs and trees.

We already had this. It's called a tree... although we seem hell-bent on cutting them all down.



Absolutely...in some areas like Wake County NC, land has been plowed under at an average rate of 4+ acres per day! That is a lot of land that is going out of production and not having trees planted on it.

Aaron:)

I think this is the associated technical paper (PDF):

http://www.ucalgary.ca/~keith/papers/97.Stolaroff.AirCaptureContactor.e.pdf

The process evaporates enormous amounts of presumably fresh water. The cost analysis explicitly does not include recovery of the sodium carbonate solution, regeneration of the sodium hydroxide, or recovery, compression, transportation and sequestration of the CO2.


The question is: is this an actual solution to the problem or a near-useless red herring?

My conclusion: near-useless red herring.

I will not pretend to understand the science behind the scrubbers, but I think the best place to store carbon is in plants ( vegetation ).

If we'd stop adding carbon into the atmosphere, the solution would be fairly simple... stop recycling paper and composting veg waste and start burying it in landfills.

Burying organic wastes is not a good idea. The buried wastes will produce methane, which is a far more potent greenhouse gas than carbon dioxide. If the organic wastes are composted, the methane problem is averted.

Burying organic wastes is not a good idea. The buried wastes will produce methane, which is a far more potent greenhouse gas than carbon dioxide. If the organic wastes are composted, the methane problem is averted.

BUT! if the landfills are tapped properly methane gas can be captured and burned to produce heat and light for homes. FWIW we compost as much as we can at our home place, recycle, reduce and reuse. Compost goes in the gardens. With 4 people in the household (more or less) we only generate a large garbage bag of trash every couple of weeks. The biggest challenge is to reduce the amount of plastic that comes in via the packaging from the grocery store. Why they insist on packaging things like bananas and corn on the cob is beyond me! We do attempt to shop conservatively and choose things that are packaged in readily recyclable materials, ie; glass, steel and aluminum.

Aaron:)

So the plan is to dig the carbon out of the ground--where it's been safely "sequestered" for 100 million years--and put it in the air. Then build big expensive machines to take it back out of the air.... and bury it in the ground again!

Does this not strike you as absolutely insane?

So the plan is to dig the carbon out of the ground--where it's been safely "sequestered" for 100 million years--and put it in the air. Then build big expensive machines to take it back out of the air.... and bury it in the ground again!

Yes, but I have a name for it: reverse coal mining. Actually, that would involve building whole mountains out of trees, then covering the tree-mountains in dirt.

Burying organic wastes is not a good idea. The buried wastes will produce methane, which is a far more potent greenhouse gas than carbon dioxide. If the organic wastes are composted, the methane problem is averted.

Quoted for truth. An additional concern is sequestering all the nutrients tied up in that organic matter: nitrogen, magnesium, etc.

We already had this. It's called a tree.

+1 :D I LOVE TREES! :love: