A Pore‐Scale Investigation of Mineral Precipitation Driven Diffusivity Change at the Column‐Scale

Mineral precipitation affects the pore structure and thus transport properties of porous media. In this study, we investigated pore-scale dynamics in diffusion controlled systems resulting impacts on effective diffusivity, using a micro-continuum reactive model. Forty two-dimensional structures representing both idealized realistic geometries were simulated with consideration different scenarios rates. A homogeneous nucleation scenario reproduced patterns observed previous experimental study showing mixing-induced precipitation, surface growth captured pattern for mineral substrate same or similar structures. all cases, local resulted reduction average porosity domain (Φ) until cessation diffusive termination precipitation. The minimum reached was referred to as critical (Φc). diffusivity (Deff) decreased Φ dropped sharply effectively zero, that is, (Deffc), Φc reached. These can be by revised relationship explicitly considers corresponding pre-exponential coefficient exponent varied initial kinetics. Overall, results systematically larger coefficients give rise sharper decrease is approached, compared scenario. also implemented at continuum scale used examine column change reactions.