Journal of Earth Science & Climatic Change
Open Access

Abstract

Monitoring of CO2 release through the ground surface is essential to verify the safety of carbon capture and storage. We conducted a small injection field test using the multichannel surface soil CO2 monitoring (SCM) system as a soil CO2 monitoring method. In the system, NDIR sensors measure CO2 concentration 10 cm above the ground surface and acrylic chambers covered the NDIR sensors to protect the sensors. Before injection, the background CO2 concentrations were monitored. They showed the distinct diurnal variation, and were positively related with relative humidity of the air, but negatively with air temperature. The daily variation of CO2 concentrations was damped with precipitation. 4.2 kg of CO2 was injected 1 m below the ground for 29 minutes. CO2 concentrations increased in the all five chambers, which were located less than 2.8 m of distance from each other. The Chamber 1, which is closest to the injection point, showed the largest increase of CO2 concentrations, while Chamber 2, 3, 4 showed the peak which is 2 times higher than the average of background CO2. The CO2concentrations decreased from the peak around 4 hours after the injection ended in Chamber 2, 4, and 5. The CO2 concentrations seem to be recovered to the background around 4 hours after the injection ended. The result of statistical analysis for determining the leakage shows that the coefficient of variation of CO2 for 30 minutes (CV30min) is efficient to determine the leakage signal, with reflecting the fast change in CO2 concentrations.

Biography

Jeong-Chan Kim has completed his PhD from Seoul National University. He is the director of Deep Geoenvironment Research Center, KIGAM (Korea Institute of Geoscience and Mineral Resources). He has published more than 20 papers in reputed journals and has been serving as a member of Geological Society of Korea.

Email: jckim@kigam.re.kr