Upscaling of Reactive Transport.
Current Funding: NSF/EAR Hydrologic Sciences, A Practical Upscaling of Reactive Transport, $566,000, 2014-2017. PI: T. R. Ginn, co-PI: J. DeJong, UC Davis.
Students: Ahmed Ali, Mohamed Nassar, Mehrdad Bastani.
Collaborators: Tanguy Le Borgne/Géosciences Rennes; Marco Dentz/Universitat Politècnica de Catalunya; Jason DeJong/UC Davis.
Project Summary: The determination of large scale biogeochemical transformations of solutes undergoing transport in porous media includes challenges ranging from geothermal energy production, to prediction of bioremediation or natural attenuation long-term reaction extent, to quantifying redox processes and/or precipitation rates in natural biogeochemical cycling. Despite decades of research on upscaling transport and characterizing biogeochemical processes, the upscaling of reactive transport remains arguably the greatest barrier surmounting these challenges. We remain essentially unable to predict multicomponent reactive transport in natural porous media. Methods for upscaling reactive transport have sidestepped complexities of biogeochemical transformations including nonlinear and coupled processes. This situation is due in part to the chasm between the physics of hydrogeological transport and the biogeochemistry of remediation processes.
O2 and Benzoate profiles showing mixing-limited degradation. Conceptual approach to upscaling.
In this project we integrate well-studied reactions with a new approach to representing transport via kinematics of mixing that focuses on the interface between displacing and displaced solutions. Using results from turbulence theory, we treat the moving interface between reacting solutions as a chain of individual strips, termed “lamellae”, and upscale mixing-limited reaction extent using the scalar dissipation of an analogous passive solute, in the lamella context, for cases where the reactions do not change the nature of the flow field. Given the way that the whole set of lamella behave (achievable for any given rendition of a porous media), the problem reduces to one of predicting the reactions on a given lamella as it evolves kinematically. This simplification reduces much of the complexity while honoring the mixing on the lamella during its advection along with the moving front. We combine mathematical physics analyses of the transport problem to develop a lamella dynamic solution for representative elementary volumes of porous media including multidomain mass transfer, and we then exercise the method in upscaling data or simulated data from two published experiments with which the we have prior modeling experience. Finally we propose a suite of controlled experiments in abiotic calcite precipitation where the front displacement is controlled, and apply our upscaling to these data as well. In all cases we combine the upscaling with “ground-truth” modeling using complete characterization.
Important papers on the topic:
- LeBorgne, T., T. R. Ginn, and M. Dentz, Impact of Fluid Deformation on Mixing-Induced Chemical Reactions in Heterogeneous Flows, Geophysical Research Letters, in press, 2014.
- Ginn, T. R., M. K. Nassar, T. Kamai, K. Klise, V. Tidwell, and S. McKenna, On a recent solute transport laboratory experiment involving sandstone and its modeling, Water Resour. Res. 49(11):7327-7338, 2013.
- Ginn, TR, Generalization of the Multirate Basis for Time-Convolution to Unequal Forward and Reverse Rates and Connection to Reactions with Memory, Water Resour. Res. 45, Art. W12419, 2009.
- Seeboonruang, U., and T. R. Ginn, Upscaling heterogeneity in aquifer reactivity via exposure-time concept: forward model, J. Contam. Hydrol., 84 (3-4): 127-154, 2006.
- Seeboonruang, U., and T. R. Ginn, Upscaling heterogeneity in aquifer reactivity via exposure-time concept: inverse model, J. Contam. Hydrol., 84(3-4): 155-177, 2006.
- Ginn, T.R. On the distribution of multi-component mixtures over generalized exposure-time in subsurface flow and reactive transport: Theory and formulations for residence-time dependent sorption/desorption with memory, Water Resour. Res. 36:2885-2894, 2000.
- Ginn, T.R. On the distribution of multi-component mixtures over generalized exposure-time in subsurface flow and reactive transport: Batch and column applications involving residence-time distributions and non-Markovian reaction kinetics, Water Resour. Res. 36:2895-2904, 2000.
- Ginn, T. R. Stochastic-convective transport with nonlinear reactions and mixing: Finite streamtube ensemble formulation for multicomponent reaction systems with intra-streamtube dispersion, J. Contam. Hydrol., 47:1-28, 2001.
