Reuters: New technologies may grab carbon right out of air

[OKIsItJustMe]

http://www.reuters.com/article/latestCrisis/idUSN01290245

New technologies may grab carbon right out of air

Thu Oct 1, 2009 5:21pm EDT

• New approach seen to combat climate-warming carbon
• Strategy would reduce atmospheric carbon concentration
• Companies investigating "air capture" method

By Deborah Zabarenko, Environment Correspondent

WASHINGTON, Oct 1 (Reuters) - As the world wrestles with how to cut greenhouse gas emissions, new technologies are gearing up to grab climate-warming carbon right out of the air.

This is different from trapping carbon dioxide as it comes out of pollution sources like factories and power plants. This so-called air capture technology could be set up anywhere and suck carbon directly from the atmosphere.

The devices to do this are varied in appearance. Some look a bit like telescopes, others involve vast, thin wall-like structures to capture the carbon. But all aim for a net reduction in atmospheric carbon, instead of just slowing down the increase of greenhouse emissions.

Because air capture need not be near carbon-belching factories, it could help the world's poorest countries, which at this point cannot benefit from the global carbon market, in which companies in developed countries get credits for investing in carbon-limiting projects in poor countries.

…

[jdlh8894]

1. Don't trees and plants do this already? n/t

[Javaman]

2. Yup, but I think the issue at hand is...

because we are approaching negetive feed back at a dizzing pace, something else needs to be put into place to help.

Cities like Bejing, Mumbai, Los Angeles, Moscow, Houston, etc, could have these "scrubbers" put into place to tackle their massive amounts of pollution right off the bat.

Make them all solar powered as well.

[OKIsItJustMe]

5. They do, but (as you may have noticed) they haven't been doing a good job of keeping up

The last time the ecosystem dealt with elevated levels of greenhouse gases, it took about 100,000 years to bring CO₂ levels down about 100ppm.



It took us about 250 years to raise them 100ppm.



Currently, we're raising them at about 1.5ppm/year:



How long do you think it will take us to reverse that trend by planting trees and plants?

(Don't get me wrong here. I'm a “tree hugger” myself, I just think they are going to need some help.)

[Nihil]

3. Content-free puff piece.

Not really worth your time posting that one but thanks for the thought.
:shrug:

[OKIsItJustMe]

6. I like to think of it as thought provoking

I grant you, Earth-shattering it is not.

[tabatha]

4. I had always wondered about that ----

since oxygen and nitrogen are sucked out of the air in plants that produce those gases.
However, a lot of air would have to be sucked to get CO2 out - since it is only present in ppm, unlike O2 and N2.

[OKIsItJustMe]

7. Here's a Nature piece from last December: Sucking carbon out of the air

http://www.nature.com/news/2008/081217/full/news.2008.1319.html

Published online 17 December 2008 | Nature | doi:10.1038/news.2008.1319

News: Briefing

Sucking carbon out of the air

Are plans to take carbon dioxide out of the air just a pipe dream, or a cure for global warming?

Nicola Jones

…

Are there any companies looking at this?

A few. Global Research Technologies, based in Tucson, Arizona, was founded in 2004 and is the biggest commercial name in the business. Graciela Chichilnisky and Peter Eisenberger of Columbia University also have a company, called Global Thermostat, founded in 2006. But many others are working in the field. David Keith of the University of Calgary in Canada is now raising funds and hopes to start a company called Carbon Engineering within a few months.

How do their devices work?

There are various schemes. One main one first extracts CO2 from the air by dissolving it in sodium hydroxide (NaOH), giving a solution of sodium carbonate (Na2CO3). To get the carbon out of solution, a trick is borrowed from the pulp and paper industry: slaked lime (Ca(OH)2) or titanium dioxide (TiO2) is added to the mix. This creates particles — of limestone (CaCO3), if you're using lime — that settle out and can be collected. These particles are then thrown into a kiln and heated to release the CO2 and regenerate the material needed (slaked lime or titanium dioxide) to keep the system running. In effect, the entire system simply separates CO2 from air and concentrates it into a pure stream, so it's suitable for use or disposal.

This is the technique that Keith is pursuing, using a fine spray of liquid NaOH to suck up as much CO2 as possible. Keith calls it "Russian tractor" technology, because it is based on very conventional chemistry, scales up well and has a low technological risk. In the near term, says Keith, that makes it a solid bet.

Another idea is to use a solid ion-exchange resin, such as those found in the water-softening industry. This is the system being mainly pursued by Global Research Technologies. They have hit on a commercially sold resin that absorbs CO2 when dry, and releases it when exposed to humid air. This provides a very simple, low-energy way to mine CO2 from the air. But, Keith notes, if the resin proves vulnerable to contamination in scaled-up systems, that will be very hard to fix.

…

[tabatha]

8. Thanks, bookmarked it.