News overview
Enough capacity for CO2 storage in US deep saline aquifers27 March 2012A new study by researchers at MIT shows that there is enough capacity in deep saline aquifers in the United States to store at least a century's worth of carbon dioxide emissions from the nation's coal-fired powerplants. Though questions remain about the economics of systems to capture and store such gases, this study addresses a major issue that has overshadowed such proposals.
Source: http://web.mit.edu/newsoffice/2012/greenhouse-gas-in-aquifers-0320.html From microns to milesThe MIT team modeled how the carbon dioxide would percolate through the rock, accounting not only for the ultimate capacity of the formations but the rate of injection that could be sustained over time. "The key is capturing the essential physics of the problem," Szulczewski says, "but simplifying it enough so it could be applied to the entire country." That meant looking at the details of trapping mechanisms in the porous rock at a scale of microns, then applying that understanding to formations that span hundreds of miles. When liquefied carbon dioxide is dissolved in salty water, the resulting fluid is denser than either of the constituents, so it naturally sinks. It's a slow process, but "once the carbon dioxide is dissolved, you've won the game," Juanes says, because the dense, heavy mixture would almost certainly never escape back to the atmosphere. |