EGEL
Energy GeoEngineering Laboratory

Engineered CO2 injection for geological storage - The Use of Surfactants

Engineered CO2 injection for geological storage - The Use of Surfactants

​Kim, S. H. and Santamarina, J. C. (2014). "Engineered CO2 injection for geological storage - The Use of Surfactants", International Journal of Greenhouse Gas Control vol. 20, pp. 324-332
Kim, S. H. and Santamarina, J. C.
Carbon dioxide, Interfacial tension, Surfactant, Engineered injection, Sweep efficiency
2014
Poor CO2 displacement efficiency can exacerbate hydro-chemo-mechanically coupled phenomena in CO2 storage reservoirs, increase the area affected by CO2 in the reservoir, and negatively impact the long-term geological storage of CO2. The injection of CO2 can be engineered using surfactants to improve displacement efficiency. Pendant and sessile drop tests show that a surfonic copolymer decreases the interfacial tension 
γfl and increases the contact angle Ɵ under reservoir conditions. The combined changesin surface tension and contact angle have a pronounced effect on the capillary factor γfl  cosƟ. Injectiontests using micro-models and pore network simulations show that a smaller capillary factor transforms the displacement pattern and enhances the pore-scale sweep efficiency of CO2, surpassing 40% in 2-D applications. Surfactant cost may offset the technical advantages identified in this study.