Reactive transport in porous media recently attracted significant attention because of its implications to important environmental issues. Multiphase fluids in the Earth are always in a close proximity or in a direct contact with solids, and the complex behavior at the fluid/solid interfaces plays an important role in the transport phenomena. The open question remains, though, about the impact of pore-scale physical and chemical heterogeneities on observed behavior at a larger scale. This question should be answered to explain discrepancies in parameters measured at different scales and discrepancy in behaviors, observed in laboratory and field experiments and predicted by macro (Darcy) scale models. Pore-scale numerical models can be a useful tool to improve the fundamental understanding of the reactive transport. Combined with upscaling, pore-scale simulations can predict key parameters and identify physiochemical processes that control macroscopic phenomena or demonstrate whether upscaling is impossible.

Despite considerable efforts, developing accurate and efficient models for pore-scale multiphase flow and reactive transport remains an ongoing challenge. Large density and viscosity contrasts and low compressibility of geological fluids are a challenge for many numerical methods. A better theoretical understanding of the behavior of fluids near to the contact line should be developed and accurate and effective ways must be found to couple hydrodynamics and contact-line dynamics. Models of mineral dissolution and precipitation should include the information of crystal structure and be coupled with chemical transport in multiphase fluid systems.

This session will be devoted to recent advances in these areas and will include: (1) methods for direct imaging and statistical reconstruction of porous media; (2) different methods to simulate reactive transport in porous media at the pore scale, including lattice-Boltzmann, pore-network, and smoothed-particle hydrodynamics methods; (3) hybrid methods to bridge a gap between different scales; and (4) different approaches to upscaling pore-scale results to the continuum scale.  Applications of these methods to subsurface contaminant migration, bioremediation, geological CO2 sequestration, etc. are particularly sought.