New option found for carbon storage

Researchers at Colombia University in New York have a patent out for using a common rock as a carbon sink to reduce greenhouse gases.

In a paper to be published by the National Academy of Sciences, they describe how their process uses peridotite, a rock that lies directly under the Earth’s crust, but which only emerges near the earth’s surface in a few locations, notably in Oman.

The researchers, Peter Kelemen and Juerg Matter of the Lamont-Doherty Earth Observatory at Colombia, say they can accelerate the process by which the peridotite naturally converts carbon dioxide into solid minerals such as calcite. They would do so by drilling down and injecting the rock with heated water containing pressurized carbon dioxide. According to their abstract: “After an initial heating step, C02 pumped at 25 or 30 degrees C can be heated to exothermic carbonation reactions that sustain high temperature and rapid reaction rates at depth with little expenditure of energy.”

They estimate “in-situ carbonation of peridotite could consume a billion tons of carbon dioxide per year in Oman alone, and believe this is a low-cost, safe and permanent method of storing carbon dioxide.

It is particularly fortuitous that the peridotite is available in a country so close to the rich oil and gas fields in the Middle East.