二酸化炭素地中貯留の数値シミュレーションにかかる特徴的な技術要素

抄録

This lecture provides an overview of the advancements in carbon capture and storage（CCS） technology and its application to numerical simulations. According to the 2023 report by the Global CCS Institute, the number of carbon capture, utilization and storage（CCUS）projects has tripled in the past five years, and in Japan, several projects have advanced to the feasibility study stage. However, the study of CCS did not begin just recently; it has a history of about 30 years. This history can be divided into three phases: the initial rise, the period of stagnation, and the current phase. The technological advancements during each period were closely related to the technologies used in oil and natural gas development.

The technology for geological carbon storage（GCS）is based on the CO₂-enhanced oil recovery（EOR）technology used in the oil and gas sectors. However, from the perspective of creating new storage reservoirs, different requirements are needed, such as pressure boundary conditions and understanding sealing layers, which differ from conventional technologies. Nevertheless, the numerical calculation methods required for these evaluations are based on simulators used in oil and gas development. Thanks to the development of simulation technologies, long-term behavior predictions for GCS have become possible. Simulators from companies like SLB, CMG, and LBLN are primarily used. These incorporate complex elements specific to GCS, such as mineral chemical reactions, rock mechanics, and heat conduction calculations, and the advancements in technology have made CCS simulations more precise. In the future, further technological innovation is expected with the development of monitoring technologies and simulation methods that utilize artificial intelligence.