A University of Virginia engineering professor has proposed a novel approach for keeping waste carbon dioxide out of the atmosphere.
Andres Clarens, an assistant professor of civil and environmental engineering at U.Va.'s School of Engineering and Applied Science, and graduate student Zhiyuan Tao have published a paper in which they estimate the amount of carbon dioxide that could be stored in hydraulically fractured shale deposits after the methane gas has been extracted. Their peer-reviewed finding was published in Environmental Science and Technology, a publication of the American Chemical Society.
The team applied their model to the Marcellus Shale geological formation in Pennsylvania and found that the fractured rock has the potential to store roughly 50 percent of the U.S. carbon dioxide emissions produced from stationary sources between 2018 and 2030. According to his estimate, about 10 to 18 gigatonnes of carbon dioxide could be stored in the Marcellus formation alone. The U.S. has several other large shale formations that could provide additional storage.
The researchers' model is based on historical and projected methane production, along with published data and models for estimating the carbon dioxide capacity of the formations. Clarens said that production records are available for how much methane gas producers have already extracted from the Marcellus Shale, as well as estimates of how much more they expect to extract. That provides a basis for determining how much space will be left in the formation when the methane is gone, he said. Clarens said gas would be adsorbed into the pores of the shale and held securely.
"This would be a way of eating our cake and having it too," Clarens said. "We can drill the shale, pump out the gas and pump in the carbon dioxide.. I think this will get policymakers' attention."
He said his work deals with the chemical feasibility of the idea, and that additional studies must be perform
|Contact: Matt Kelly|
University of Virginia