Development of Methods for Gaseous Phase Geochemical Monitoring on the Surface and in the Intermediate Overburden Strata of Geological CO2 Storage Sites

摘要

Development of Methods for Gaseous Phase Geochemical Monitoring on the Surface and in the Intermediate Overburden Strata of Geological CO2 Storage Sites - The developments and results presented in this paper are taken from the work carried out as part of the GeoCarbon-Monitoring project, which was partly funded by the French National Research Agency (ANR). An important part of this project covers methods for gas monitoring on the surface as well as within the cap rock of geological CO2 storage sites. The work undertaken by INERIS was targeted at two specific approaches which are often recommended as essential for the monitoring of future storage sites: - early detection (pre-alert), based on the sampling and analysis of gas at the bottom of the dedicated boreholes which are drilled from the surface into the intermediate cap rock strata; - the detection and quantification of the gaseous flux of CO2 released from the ground into the atmosphere. These two approaches were developed in the laboratory successively and then applied and tested in-situ, under conditions that are as close as possible to those of the future storage sites. They offer the advantage of ensuring a direct measurement as well as providing real-time information on the presence or, on the contrary, the absence of CO2 leaks.