Monday, November 17, 2008

Here's a fascinating geological study, coming at a time when humans are so desperately looking for ways to reduce greenhouse gases:

Rocks called peridotite, which are found deep in the earth in the mantle, but which are sometimes exposed to the earth's surface by colliding tectonic places, may hold a massive potential for absorbing and sequestering carbon dioxide produced by human consumption of fossil fuels. The ability of these rocks -- which appear on the surface of the earth in large quantities in Oman and in smaller amounts at other sites around the world, including the western U.S. -- to turn carbon dioxide into solid carbonates like limestone or marble, has been known for some time, but now it is believed the process could be made fast and effective for very large quantities of CO2.

The idea would be to pressurize CO2 in water and artificially transport it to places where the rock exists. By boring holes in the rock and piping in the water, a reaction would begin to absorb the carbon. Heat generated by this reaction would then cause the rock to crack and make it possible for even more carbon to be absorbed more quickly.

Accounting for engineering challenges and other imperfections, [the scientists] assert that Oman alone could probably absorb some 4 billion tons of atmospheric carbon a year—a substantial part of the 30 billion sent into the atmosphere by humans, mainly through burning of fuels.

The scientists believe this may be one part of a complete package for sequestering carbon. Trials involving another rock that absorbs carbon are beginning shortly in Iceland.

No comments: