LATTICE BOLTZMANN METHOD FOR REACTING FLOW IN POROUS MEDIA

We present a numerical framework based on the lattice Boltzmann method (LBM) for modeling reacting flow in porous media at the pore scale. Our numerical model accounts for multiple processes at the fundamental scale of a single pore volume, including fluid flow, diffusion and advection of species, adsorption-desorption and mineral precipitation/dissolution reactions, as well as the evolution of pore geometry due to dissolution/precipitation. Homogeneous reactions are described either kinetically or through local equilibrium mass action relations. Heterogeneous reactions are incorporated into the LBM through boundary conditions imposed at the mineral surface. The LBM can provide detailed information on local fields, such as fluid velocities, solute concentrations, mineral compositions and amounts, as well as the evolution of pore geometry due to chemical reactions. Presented are simulation examples including crystal growth from supersaturated solution, precipitation of a mineral with evolving geometry, injection of CO₂ into a limestone rock, and bacterial growth in micromodels.

This approach is being applied in a broad spectrum of energy, environmental, and biological research, including clean energy exploitation (fuel cells and batteries), enhanced oil recovery and geothermal systems, nuclear waste disposal, geologic CO₂ sequestration, underground contaminant migration, biomedical engineering applications, and novel materials design. Particularly, perspectives of applying this method to seafloor hydrothermal systems are discussed.