F204 多孔質内における超臨界CO_2の毛管力トラップ現象のミクロスケール可視化(OS11 温暖化対策とCO_2削減技術),動力エネルギーシステム部門20周年,次の20年への新展開)

抄録

Residual gas trapping, where gas bubbles are trapped in porous media by capillarity, is an important trapping mechanism in CO_2 geological storage. Stability of trapped gas bubbles is an essential issue to insure the safety of geological storage. In previous study, we visualized trapped gas bubbles in sandstone at ordinary temperature and pressure. In present study, we directly visualize trapped CO_2 bubbles in a supercritical phase from a microscopic point of view. At the condition which corresponds to the depth of 850m, we found supercritical CO_2 bubbles were trapped as non-wetting phase compared to water and is in the porous media.