Characterizing the spatial distribution of CO2 leakage from the shallow CO2 release experiment in South Korea. (May 2018)

• Record Type: Journal Article
• Authors: Kim, Hyun-Jun; Han, Seung Hyun; Kim, Seongjun; Yun, Seong-Taek; Jun, Seong-Chun; Oh, Yun-Yeong; Son, Yowhan
• Is Part Of: International journal of greenhouse gas control. Volume 72(2018)
• Page Start: 152
• Page End: 162
• Publication Date: 2018-05
• Subjects: CO2 leakage -- Environmental impact assessment -- K-COSEM -- Monitoring technique -- Indicator; Greenhouse gases -- Environmental aspects -- Periodicals; Air -- Purification -- Technological innovations -- Periodicals; Gaz à effet de serre -- Périodiques; Gaz à effet de serre -- Réduction -- Périodiques; Air -- Purification -- Technological innovations; Greenhouse gases -- Environmental aspects; Periodicals; 363.73874605
• DOI: 10.1016/j.ijggc.2018.03.015
• Languages: English
• ISSNs: 1750-5836

Abstract

Highlights: The spatial distribution of CO2 leakage was characterized from the shallow CO2 release experiment. CO2 gas was released at small areas of surface leakage (within a 10-m radius). Long-term monitoring should be conducted for the environmental risk assessment because of the remaining CO2 gas after the end of injection. CO2 leakage with low levels could be detected through some indicators such as the non-linear regression and CO2 :O2 ratio. Abstract: This study was conducted to detect and characterize potential CO2 leakage from the K-COSEM shallow CO2 release experiment. The study site was established in Eumseong, South Korea, and consisted of five zones divided into two lines (east and west). Approximately 1.8 t CO2 was injected from the perforated release well at Zones 1–4 from June 1–30, 2016. CO2 fluxes varied due to the uneven permeability of soil, and CO2 leakage at the surface was detected within small area (<10 m across). In-soil CO2 concentrations within 5 m from the well were also significantly higher than those measured at 10 m from the well. These results confirmed that the spatial distribution of in-soil CO2 is strongly affected by soil properties and atmospheric pressure effects. Non-linear regression and CO2 :O2 ratio analyses were conducted to determine whether there is a CO2 leakage. Even though maximum CO2 concentrations at some leak points were as low as the background concentration, CO2 concentration clearly increased. The CO2 :O2 ratios from the CO2 release experiments were completely different from the ratios associated with the biological reaction. Those methods seem to be practical use as indicators of CO2 leakage detection.