CO2 capture and storage
CO2 capture and storage (CCS) has gained global interest due to its potential to reduce the impact of CO2 on climate change. CO2 sequestration in deep geological formations is one of most suitable solutions for CCS so far. Three main geological formations provide potential to store CO2 : depleted oil or gas reservoirs, saline formations, and coal seams. During the early storage phase (10 years – 100 years) for CO2 sequestration, injected CO2 is mainly trapped by structural or stratigraphic mechanisms relying on the existence of a caprock formation of low permeability that acts as a barrier to the CO2 flow. Chemical trapping, such as mineralization, offers a very long-term storage capacity (>1000 years). The influence, on the surrounding environment, of mechanical and chemical changes, as well as heat effects during CO2 injection are not well-known. Research for a better understanding of complex modelling and experimental issues is essential for the enhancement of field studies so as to provide benchmarks for developing reliable solutions to geo-environmental problems.
Research Group for CO2 Storage
Visualising the impact of CO2 on the microstructure of an argillaceous caprock
The project aims to capture the structural modifications of a potential caprock formation due to supercritical CO2 with in-situ 3D imaging. The outcome of this research aims to introduce an innovative approach for a better understanding of the complex multiphysical mechanisms involved in the context of safe geological CO2 sequestration. This research is carried out thanks to Swiss National Science Foundation (SNSF) Spark funding awarded to Eleni Stavropoulou, PhD, who specializes in studying the coupled behaviour of shale caprocks in different scales.
CS-C Experiment: Experimental assessment of shale properties for safe geological CO2 storage – sponsored by Mont Terri consortium (Swisstopo)
The storage of carbon dioxide (CO2) in underground reservoir formation strongly relies on the presence of impermeable caprock formations to prevent the migration of CO2 towards the surface. Shales are considered among the best candidates caprock formation due to their low permeability, high water retention properties, and self-sealing capacity. The goal of this project is the experimental assessment of the sealing capacity and integrity of the Opalinus Clay that is considered as representative shale caprock formation. Swisstopo ( Mont Terri project ) and FANC are partners of this project.
PhD Research Project
Geomechanical response of geomaterials to chemical reaction with CO2 – Taeheon Kim
In order to fully understand the ground response to CO2, the long term chemical effects of CO2 on the host ground should be identified. Much experimental evidence suggests that the long term dissolution and precipitation effects of CO2 on the host materials are non-negligible, however, there are still struggles in quantification. In our lab, we are attempting to quantify the mechanical response of geomaterials to acidic fluid focusing on the effect of mineral dissolution. Along with constitutive model development and experiments are being conducted using the advanced high-pressure oedometer cell invented in our lab and the high-pressure triaxial cell which we can simulate the in situ reservoir stress conditions. By taking both approaches, we aim to achieve confidence in the developed model and a better understanding of the long term geomechanical behaviour to CO2 injection.
The Chair is actively participating to the activities of the SCCER-SoE. The goal of the consortium is to perform innovative research in the context of geo-energy and hydropower. In particular the Chair is contributing to the work package 1 (WP1), leaded by Prof. Lyesse Laloui, with scientific activities in the context of carbon dioxide sequestration. Experimental studies are currently carried out to investigate shaly caprock formations. Numerical analyses are also performed to forecast seismicity induced by fluid injection and production.
This project is part of the European initiative ACT (Accelerating CCS Technologies) to facilitate research, development, and innovation in the context of carbon capture storage (CCS) and utilization. The Elegancy project aims at combining CCS with hydrogen production; as large quantities of carbon dioxide (CO2) are obtained during the production of hydrogen, CCS is needed to keep the hydrogen energy source clean. The Swiss partners are participating to the Elegancy project through the SCCER-SoE by performing an in-situ experiment to assess the sealing capacity and integrity of a faulted caprock formation. The experiment is planned in the Mont Terri URL and aims at analysing the physical phenomena controlling the migration of CO2-rich brine in the faulted caprock, along with the impact on mechanical and transport properties of the damaged caprock. The Chair is contributing to the project with experimental activities at the laboratory scale to characterize the material (Opalinus Clay) extracted from the drilled boreholes for injection and monitoring. Parameters governing the mechanical response and the transport of CO2-rich brine in the Opalinus Clay are investigated to provide consistent data for the performance of numerical simulation. The experimental activities are carried out in collaboration with ETH Zurich, and Imperial College London.
Waste water injection in sedimentary sequences has been seen to cause induced seismicity in the basement rocks below. This seismicity may also pose a threat to potential CO2 sequestration operations. Switzerland, especially, has already had problems with induced seismicity. The most notable case being in Basel in 2006, when magnitude 3+ earthquakes were induced during EGS stimulation and were enough to bring the project to a halt. Clearly, the magnitude 5+ earthquakes seen during waste water injection can therefore also pose a threat. The chair “Gaz Naturel” performs quantitative seismic risk analysis accounting for the lithology differences between the sedimentary sequences where injection is occurring and the crystalline basement rock below.
Séquestration du CO2: remettre le carbone à sa place2020-12-04.
Laboratory Study on the Volumetric Response of Gas Shale Samples with Controlled Pore Fluid PressuresSymposium on Coupled Processes in Radioactive Waste Disposal and Subsurface Engineering Applications (DECOVALEX 2019), Brugg, Switzerland, November 4-5, 2019.
Compaction-induced permeability loss’s effect on induced seismicity during reservoir depletionPure and Applied Geophysics. 2019. Vol. 176, p. 4277–4296. DOI : 10.1007/s00024-019-02198-0.
Experimental assessment of shale properties for safe geological CO2 storage
NAGRA Project Order 15’228 EBS – Task Force: Homogenization Analysis of Bentonite & Gas Transport in Bentonite