CO2 地中貯留の鉱物トラップ再現実験による 砂岩の力学・透水特性評価

Abstract

CCS has been expected as a countermeasure against global warming in recent years. When the injected CO2 reacts to rock minerals, it may form secondary minerals such as calcite, which is called mineral trapping of CO2. It is of significant importance to examine how the mineral trapping exerts an influence on the physical properties in the targeted reservoir rocks because the trapped minerals may change the strength, deformability, and permeability of the reservoir rocks, although such works are quite sparse in literature. In this study, the influence of the mineral trapping on the evolution of physical properties has been evaluated by replicating precipitation of calcium carbonate that may occur in the mineral trapping. The results of mechanical and permeability experiments show that the change of the mechanical and hydraulic properties is significant even if the amount of calcite precipitation is relatively small.