  Predicting the geometrical evolution of the pore space in geological
formations due to fluid-solid interactions has applications in reservoir
engineering, oil recovery, and geological storage of carbon dioxide. However,
modeling frameworks that combine fluid flow with physical and chemical
processes at a rock's pore scale are scarce. Here, we report a method for
modeling a rock's pore space as a network of connected capillaries and to
simulate the capillary diameter modifications caused by reactive flow
processes. Specifically, we model mineral erosion, deposition, dissolution, and
precipitation processes by solving the transport equations iteratively,
computing diameter changes within each capillary of the network simultaneously.
Our automated modeling framework enables simulations on digital rock samples as
large as (1.125mm)$^3$ with 125$\times 10^6$ voxels within seconds of CPU time
per iteration. As an application of the computational method, we have simulated
brine injection and calcium carbonate precipitation in sandstone. For
quantitatively comparing simulation results obtained with models predicting
either a constant or a flow-rate dependent precipitation, we track the
time-dependent capillary diameter distribution as well as the permeability of
the connected pore space. For validation and reuse, we have made the automated
simulation workflow, the reactive flow model library, and the digital rock
samples available in public repositories.
