oa Laboratory Evaluation of Physical Variability of Multiphase Flow During CO2 Sequestration

This study explores the physical variability of multiphase flow during CO2 sequestration through repeated injections in a large-scale laboratory setup called the FluidFlower. The FluidFlower allows real-time observation of CO2 flow patterns in a reservoir constructed from unconsolidated sand. The reservoir is based on seismic images from the Horda Platform. Gaseous CO2 is injected under controlled conditions, into the reservoir which is saturated with a pH-sensitive dye solution, enabling the tracking of both dissolved and free CO2.

A specialized Python package, DarSIA, processes time-lapse images from the experiments, and identifies the contours of the different phases. This provides the opportunity to quantify the degree of overlap across multiple experiments. Despite injecting the same mass of CO2 from the same injection wells, significant variability in flow patterns emerged during the injection phase, suggesting that the heterogeneity of the sand layers strongly influenced the distribution of CO2 in the system. However, as time progressed, the flow patterns converged again due to gravitational effects on dissolved CO2. These results underscore the importance of understanding flow variability in complex geological formations to improve the safety of CO2 storage and predict long-term behaviour in storage sites.