Continuous increasing of CO2 emission is observed to a main potential reason of global warning, while CO2 geological sequestration (CGS) offers a promising technique to solve this huge environmental challenge that the world has to face today. There are, however, still some unsolved problems in CGS procedure, which is determined by pore-scale displacement mechanisms. In this study, we investigate the drainage and imbibition process of CO2-brine-glass beads system under reservoir conditions. A micro-focused X-ray computed tomography (micro-CT) machine with high resolution was introduced to imaging CO2/brine displacement and analyse the pore-scale mechanisms. The result shows that, CO2 is continuous and brine phase remains in small pores and throats in drainage. The shape of CO2/brine meniscus indicates that glass beads behave intermediate wet. While in imbibition, the effect of pore-scale displacement mechanisms become significant, piston-like front was observed at pore scale, CO2 phase is cracked and forms isolated ganglia by snap off events.
Lv, P., Wang, Z., Liu, Y., Dong, H., Jiang, L., Song, Y., … Liu, S. (2017). Pore-scale Displacement Mechanisms Investigation in CO2-brine-glass Beads System. In Energy Procedia (Vol. 105, pp. 4122–4127). Elsevier Ltd. https://doi.org/10.1016/j.egypro.2017.03.875