단층을 통한 CO2 누출에 관한 수치 시뮬레이션 연구

Abstract

Many carbon capture and storage projects are underway all over the world to reduce greenhouse gas emissions. In this study, we numerically analyze the movement of injected CO2 through the faults undetected prior to injection. We use TOUGH2-MP ECO2N software to estimate the behavior of injected and leaked CO2. The storage site is 100 m thick saline aquifer located 850 m under the shallow continental shelf. It is assumed that CO2 is first leaked through the 1st fault located 400 m away from injection well and then leaked to the seabed through the 2nd fault located 400 m away from 1st fault. We vary the injection rate of CO2 to 0.25, 0.50, and 0.75 MtCO2/year to analyze the effect of injection rate. For 0.25 MtCO2/year injection rate, no leakage is calculated, however, for 0.50 and 0.75 MtCO2/year, the leakages of CO2 to seabed are detected. The starting times of leakage at 0.5 and 0.75 MtCO2/year injection rates are 22.9 and 17.8 years, respectively. The ratios of total leaked CO2 to total injected CO2 at 0.5 and 0.75 MtCO2/year injection rates are 8% and 16.4%, respectively.