The Laloui Group joins Swiss project into carbon capture and storage

The Laloui Group has joined a first-of-its-kind exploration of Carbon Capture and Storage technology. Following approval by the Swiss Federal Government, EPFL’s Laboratory of Soil Mechanics will join a Swiss consortium led by ETHZ which includes a broad range of industry and research/academic partners. The objective of the consortium is to investigate the feasibility of storing carbon captured from the atmosphere deep underground to combat climate change.

The project consists of two main areas of focus. The first, known as DemoUpCARMA (Demonstration and Upscaling of CARbon dioxide MAnagement solutions for a net-zero Switzerland), was able to successfully demonstrate the capture of atmospheric carbon. Project partner Carbfix, an Icelandic academic-industrial partnership, showed that it is possible to store dissolved CO2 in seawater in basaltic rock formations.

Now approved by the Swiss authorities, the project known as DemoUpStorage will explore the transportation and injection of this carbon-rich water into deep basaltic repositories in Iceland where, over time, it will be permanently stored through mineralization turning the CO2 into stone and locking the carbon away forever. However, to ensure the success of the project a deeper understanding of the interactions between the host basalt rock reservoir and the CO2 rich seawater is needed.

DemoUpCARMA will explore the transportation of Swiss CO2 and for the first time dissolved in seawater its injection into Basaltic reservoirs. The Laloui Group has been asked to join the consortium due to its expertise in hydromechanical characterization of geomaterials and microstructural analysis with live x-ray imaging. Headed by Dr Eleni Stavropoulou, the team has been tasked with:

• providing a mineralogical, petrophysical and hydromechanical characterization of the field cores,
• evaluating the coupled geomechanical and geochemical response of basalt reservoir rocks to CO₂-rich seawater injection under realistic conditions, and
• quantifying the time-dependent response of mineral trapping

Stavropoulou says the Laloui Group has an important role to play in the project. “One of our fundamental objectives is to characterize the connected porosity of basalts and determine how the injection of CO2-rich seawater affects the material’s microstructure. This will give us an understanding of the transport properties of the host rock to achieve efficient and optimal injection of the CO2” she said.

The tools required to assess the impacts rely on cutting-edge image analysis. X-ray tomography allows the visualization of the material’s microstructure in 3D “This is a powerful tool that enables access to precious information that cannot be obtained with conventional laboratory testing“ explains Stavropoulou. “We can reconstruct the precise architecture of the material’s porosity and solid phases and identify zones prone to CO2 mineralization. This 3D microstructural map allows us to build representative network models and simulate our lab-based injection tests that are necessary for successful upscaling!”

Whilst initial experiments will explore the micro-scale, the project will analyze larger, real-world scenarios. Based on the hydromechanical results generated by the experiments, Stavropoulou and her team will then develop a model which will be used to further enhance the calibration and resolution of the field-scale models developed throughout the DemoUpStorage project.

Dr Eleni Stavropoulou is a Scientist at the Laloui Group at EPFL, Switzerland.