KAIST team shows direct recovery of methane from hydrates using CO2 or CO2/N2 mixture
22 June 2012
Researchers at the KAIST Graduate School of EEWS (Earth, Environment, Water and Sustainability) in South Korea have demonstrated the direct recovery of methane from massive methane hydrates (MHs), artificial MH-bearing clays, and natural MH-bearing sediments using either CO2 or a CO2/N2 gas mixture (20 mol % of CO2 and 80 mol % of N2, reproducing flue gas from a power plant) for methane replacement in complex marine systems.
A paper on their work is published in the journal ChemSusChem. The results, the team suggests, can provide an essential physicochemical background required for large-scale natural gas hydrates NGH production under the seabed.
Natural gas hydrates (NGHs) can be converted into CO2 hydrate by a swapping mechanism. The overall process serves a dual purpose: it is a means of sustainable energy-source exploitation and greenhouse-gas sequestration. In particular, scant attention has been paid to the natural sediment clay portion in deep-sea gas hydrates, which is capable of storing a tremendous amount of NGH. The clay interlayer provides a unique chemical–physical environment for gas hydrates. Herein, for the first time, we pull out methane from intercalated methane hydrates in a clay interlayer using CO2 and a CO2/N2 gas mixture.
Resources
Koh, D.-Y., Kang, H., Kim, D.-O., Park, J., Cha, M. and Lee, H. (2012), Recovery of Methane from Gas Hydrates Intercalated within Natural Sediments Using CO2 and a CO2/N2 Gas Mixture. ChemSusChem. doi: 10.1002/cssc.201100644
It is looking more and more as though exploitation of methane hydrates is going to happen, and perhaps not that far off.
Of course the truly handy thing about this is that it is carbon neutral or better.
Posted by: Davemart | 22 June 2012 at 01:09 PM
It also sounds like a climate warming neutral way of powering fuel cell cars.
Posted by: Davemart | 22 June 2012 at 01:20 PM
That's especially true if you extracted the methane, steam-reformed it to hydrogen and put the CO2 back in place.
Posted by: Engineer-Poet | 22 June 2012 at 06:17 PM
Can you imagine a machine crawling along the seabed and doing that conversion to H2 at the spot?.. I'm sure all the H2 lovers would be ecstatic
Posted by: Herm | 23 June 2012 at 01:40 AM
I imagined such a thing several years ago.
Posted by: Engineer-Poet | 23 June 2012 at 05:04 AM
I guess you could have a CCGT and grid connection off shore with a rig or two extracting the gas, creating electricity then using the exhaust as the source of the CO2
Posted by: 3PeaceSweet | 23 June 2012 at 05:14 AM
SOFCs can do auto-reforming and would be superior if electricity was needed at the site; the transport of oxygen across the electrolyte eliminates nitrogen contamination of the fuel/reformate stream.
Posted by: Engineer-Poet | 23 June 2012 at 10:48 AM