Geochemical Feasibility of Aquifer Rocks for CO2 Sequestration

Geologists at Kansas State University are part of a statewide study to test the feasibility of aquifer rocks for permanent storage of CO₂. Production of CO₂ has been associated with climate change.

Saugata Datta and Robin Barker, the geologists, are performing the study on the Arbuckle aquifer, which is under Kansas. The aquifer consists of porous rock and groundwater with such high salt concentrations that it is not fit for consumption. In the first phase of the study, the geologists are studying the rock core and water samples to observe their mineralogical composition and interaction using mass spectrometers and ion chromatography.

Water provides an indication of activities that occur in the subsurface. It can indicate the effect to the subsurface, the environment and the long term effect due to injection of CO₂.

In the second phase, the researchers are geochemically modeling the reaction when the injection of CO₂ is done into the aquifer rocks. They are utilizing drill core samples, CO₂ and brine from the aquifer.

In 2013, the third phase will commence wherein 40,000 t of compressed CO₂ will be injected below the aquifer and 30,000 t of CO₂ will be injected into an oil reservoir. The study will involve a number of sampling techniques to study the CO₂ in the aquifer. Silicates and other such minerals have the capability to trap CO₂ and transform it into a mineral. This will prevent the release of CO₂ into the atmosphere.

The Kansas Geological Survey, Wichita-based BEREXCO, Sandia Technologies, University of Kansas and the Lawrence Berkley National Laboratories are collaborating in the project. The U.S. Department of Energy has awarded four grants to the Kansas State University for this study.