New process may fight climate change by storing billions of tons of CO2 in rock
mongabay.com
November 4, 2008
Accelerating a natural carbon uptake process could help offset emissions on a massive scale, argue scientists.
Researchers may have devised a way to store massive amounts of carbon dioxide in rock through a relatively simple process. The finding is described in this week’s issue of the Proceedings of the National Academy of Sciences (PNAS).
With concerns over climate change rising, the search is on for ways to safely sequester atmospheric carbon dioxide. A solution could help avoid the worst effects of global warming while offering lucrative returns for its inventors.
Fittingly Peter B. Kelemen and Jürg Matter of Columbia University have filed for a patent on a technique that could potentially store billions of tons of CO2 in exposed peridotite, the dominant rock of the upper part of the Earth’s mantle, by accelerating a natural ‘carbonation’ process.
 Carbonate veins and massive travertine ‘inflating’ carbonate cemented, peridotite cobble conglomerate and young alluvial fan deposits. Sampling stalactites forming beneath overhang in peridotite cobble conglomerate. Courtesy of the authors. |
The approach consists of drilling into a layer of peridotite which is fractured and heated. Purified CO2 is then injected at elevated pressure and pumped at 25 or 30 °C. The process rapidly stores CO2 in the peridotite.
“In situ carbonation of peridotite could consume >1 billion tons of CO2 per year in Oman alone, affording a low-cost, safe, and permanent method to capture and store atmospheric CO2,” write the authors.
Kelemen and Matter base their projections on the discovery that carbonate veins in mantle peridotite in Oman have an average carbon-14 age of26,000 years, rather than the 30–95 million years old previously believed, showing that atmospheric CO2 can be rapidly converted to solid carbonate minerals via peridotite
weathering.
Peter B. Kelemen and Jürg Matter. In situ carbonation of peridotite for CO2 storage. PNAS Early Edition Nov 3, 2008
