Reactive Transport in Microfluidics Porous Media

Precipitation in porous media has a wide range of industrial and environmental applications such as oil recovery and lithium battery decay, as well as potential for optimized carbon dioxide storage. We design and produce low-cost porous media micromodels to study reactive transport in porous media. We quantify the fluid mixing between two miscible model fluids, water and glycerol, using optical microscopy, and measure fluid concentration as we vary the advection rates of each phase. Miscible displacement is initially dominated by diffusion, where relatively uniform low concentration of the invading phase is present; gradually, a transverse mixing border zone is established between the two fluid phases. We find a positive correlation between medium saturation and advection rate. Moreover, the medium relative permeability to water linearly increases with water flow rate, confirming the advection-dominated behavior.