Pore-Scale Process Coupling and Effective Surface Reaction Rates in Heterogeneous Subsurface Materials

Journal Article · Tue Sep 01 04:00:00 EDT 2015 · Reviews in Mineralogy and Geochemistry, 80(1):191-216

DOI:https://doi.org/10.2138/rmg.2015.80.06· OSTI ID:1214889

Liu, Chongxuan; Liu, Yuanyuan; Kerisit, Sebastien N.; Zachara, John M.

This manuscript provides a review of pore-scale researches in literature including experimental and numerical approaches, and scale-dependent behavior of geochemical and biogeochemical reaction rates in heterogeneous porous media. A mathematical equation that can be used to predict the scale-dependent behavior of geochemical reaction rates in heterogeneous porous media has been derived. The derived effective rate expression explicitly links the effective reaction rate constant to the intrinsic rate constant, and to the pore-scale variations in reactant concentrations in porous media. Molecular simulations to calculate the intrinsic rate constants were provided. A few examples of pore-scale simulations were used to demonstrate the application of the equation to calculate effective rate constants in heterogeneous materials. The results indicate that the deviation of effective rate constant from the intrinsic rate in heterogeneous porous media is caused by the pore-scale distributions of reactants and their correlation, which are affected by the pore-scale coupling of reactions and transport.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1214889
• Report Number(s): PNNL-SA-106979; 48590; KP1702030
• Journal Information: Reviews in Mineralogy and Geochemistry, 80(1):191-216, Journal Name: Reviews in Mineralogy and Geochemistry, 80(1):191-216
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory
pore scale
pore scale simulations
rate constant scaling
rate scaling
scaling
surface reactions