Flow heterogeneity controls dissolution dynamics in topologically complex rocks

Rock dissolution is a common subsurface geochemical reaction affecting pore space properties, crucial for reservoir stimulation, carbon storage, and geothermal energy. Predictive models for dissolution remain limited due to incomplete understanding of the mechanisms involved. We examine the influence of flow, transport, and reaction regimes on mineral dissolution using time-resolved data from 3D rocks. We find that initial pore structure significantly influences the dissolution pattern, with reaction rates up to two orders of magnitude lower than batch conditions given solute and fluid-solid boundary constraints. Flow unevenness determines the location and rate of dissolution. We propose two models describing expected dissolution patterns and effective reaction rates based on dimensionless metrics for flow, transport, and reaction. Finally, we analyze feedback between evolving flow and pore structure to understand conditions that regulate/reinforce dissolution hotspots. Our findings und..., This data set contains (a) the initial steady-state Eulerian flow field at the pore-scale and (b) the temporal evolution of the dissolution reaction rate for various rock samples considered in this study. Briefly, for resolving the flow field, binary 3D rock images at time t=0 are used as the geometric boundaries in which the Navier-Stokes equations are solved numerically with the finite volume method (FlowDict, Math2Market). The boundary conditions imposed a uniform pressure gradient of 1kPa at opposite boundaries of each sample volume. For tracking the evolution of the reaction rate, reactive transport simulations are performed with the Digital Rock Physics module of GeoDict (Math2Market), starting with the initial rock image. Briefly, each dissolution simulation is run in so-called batches. During each batch, (i) the pore geometry is updated, (ii) the flow within that geometry is resolved to achieve an average linear velocity corresponding to the desired Peclet number of the study (i..., , # Flow heterogeneity controls dissolution reaction behavior in geologic porous media

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This dataset contains flow field and effective reaction rate information for 26 different dissolution rock experiments and simulations. Specifics on the imposed hydrodynamics (Peclet, Damkohler, and Kinetic numbers), initial flow heterogeneity (percolation threshold), mineralogy and batch reaction rate, converged effective reaction rate, and microtomography scan dimensions and resolution are given in a summary table (`DataSummaryTable.csv`). This file contains the sample dimensions (nx, ny, nz) in units of pixels; the voxel size in microns; initial_pc, Pe, advective Damkohler (adv_Da), and diffusive Damkohler (diff_Da) in dimensionless units; batch reaction rate and converged effective reaction rate in units of mol/m^2 s; and reaction ratio in dimensionless units.

The Eulerian flow fields were computed in the pore space of each sample’s segmented microtomography scan using the FlowDict module of ...,