Thursday, November 06, 2008

Peridotite as CO2 Storage

Peridotite is a rock that looks like the picture over there --->
and it's not just any rock. It is actually the most common rock in the mantle. It is also the birthstone for August, peridote. Now, lets see if I can simplify this....

Recently these two rock docs, geologist Peter Kelemen and geochemist Juerg Matter have conducted studies on this rock and it's ability to absorb (react actually) carbon dioxide. They took the process another step and figured out a method to speed up the reaction rate by 100,000 times or more. The method involves drilling holes into the peridoitie and injecting the rock formation with really hot water and pressurized CO2. I presume that the H2O and CO2 will react with the chemical composition of the peridotite (like: magnesium, iron, oxygen, silicon, aluminum, sodium, potassium).

This is big news for the battle against anthropogenic CO2 in the atmosphere, which has been shown to be increasing for many years. This graph (the keeling curve) is perhaps the most well know and convincing evidence.The study our hero rock docs have coming out on November 11 in the Proceedings of the Natural Academy of Sciences will, I presume, layout in more detail the findings of the study and calculations on storage capacities and costs and all that shit. In the web-articles I have found, they are saying that as much as 4 to 5 billions tons per year will be able to be stored. Humans are currently spewing about 30 billion tons each year, so the amount of capture is significant.

I've done a previous post on carbon trapping before, HERE. That method involved pumping the CO2 in to really deep (many kilometers) aquifers. This has the potential issues of leakage, pH, stabilization and doesn't provide the same extreme long term storage solution that peridodite storage does. The peridotite storage, insofar as I can tell, is a chemical reaction with a crystal (calcite) as the resulting permanent storage device.

from that earlier post I wrote, standby and add:
Carbon Capture and Storage SlingShot Thoughts:
  • We have to try. This echos' my thoughts on geoengineering in general (1,2,3,4).
  • We have less than 50 years to turn this Carbon ship around. More like 1 year.
  • It is VERY unlikely that the coal fired plants will be retrofitted with CS facilities within 50 years.
  • The human effect on the atmosphere in undeniable. see Keeling Curve.
  • The Earth has great natural carbon sinks. Like the oceans and trees and now peridodite.
  • Humans are overwhelming the system.
  • Carbon sequestration can work but it is only a small part of the solution. Alternatively- we will probably need multiple methods, perhaps geographical.
  • Humans suck and there is nothing you can do about it.


  1. I own shares in Statoil, albeit very few shares, but they're a Norwegian oil company that does CO2 carbon capturing. Does it make fiscal sense? No, Statoil does it, because it's a part-private, part-publicly owned oil company that's mandated by the government to do it.

    In any case, if you're interested in big oil doing it, check Statoil.


    - D

  2. Hey D.
    Actually I dont thinks its mandated by the government. What the Norwedgian government did was essentially make the carbon and emissions tax so high that it became less expensive to sequester the CO2 than to pay to release it.