Investigations of CO2 gas dissolution during flow using 3D printed micromodels and Computational Fluid Dynamics

Abstract:

One of the dominating mechanisms occurring during CO₂ sequestration is the dissolution of CO₂. Recent advances in three-dimensional (3D) printing have enabled cheap and fast manufacturing of complex porosity models for repeatable investigations of flow processes including sensitivity analysis for small geometry alternations. Direct Numerical Simulations (DNS) allows for numerical investigation of interfacial mass transfer during CO₂ dissolution processes. Yet there is lack of experimental work that can validate existing numerical models. Benchmark datasets to compare with Direct Numerical Simulation have been limited to using semi-analytical methods for Bubble Column Reactors (BCR) where a gas bubble rises and dissolves in a water column (Fleckenstein & Bothe, 2015).

In this work we image a trapped CO₂ bubble in a single 3D printed pore geometry with a light microscope during dissolution. We then compare these experimental results with numerical simulations performed with the Continuous Species Transfer (CST) method, which was implemented in GeoChemFoam, our in-house CFD reactive transport software. We show how different differencing schemes lead to 14% difference when estimating the mass evolution of the CO₂ during the dissolution. We also compare the results with the existing semi-analytical solution for a rising bubble in a water column. Our results suggest that 3D printed micromodels can be used to experimentally investigate CO₂ dissolution processes and perform a geometrical sensitivity analysis.