Effects of network dissolution changes on pore-to-core upscaled reaction rates for kaolinite and anorthite reactions under acidic conditions

Handle URI:
http://hdl.handle.net/10754/552135
Title:
Effects of network dissolution changes on pore-to-core upscaled reaction rates for kaolinite and anorthite reactions under acidic conditions
Authors:
Kim, Daesang; Lindquist, W. Brent
Abstract:
We have extended reactive flow simulation in pore-network models to include geometric changes in the medium from dissolution effects. These effects include changes in pore volume and reactive surface area, as well as topological changes that open new connections. The computed changes were based upon a mineral map from an X-ray computed tomography image of a sandstone core. We studied the effect of these changes on upscaled (pore-scale to core-scale) reaction rates and compared against the predictions of a continuum model. Specifically, we modeled anorthite and kaolinite reactions under acidic flow conditions during which the anorthite reactions remain far from equilibrium (dissolution only), while the kaolinite reactions can be near-equilibrium. Under dissolution changes, core-scale reaction rates continuously and nonlinearly evolved in time. At higher injection rates, agreement with predictions of the continuum model degraded significantly. For the far-from-equilibrium reaction, our results indicate that the ability to correctly capture the heterogeneity in dissolution changes in the reactive mineral surface area is critical to accurately predict upscaled reaction rates. For the near-equilibrium reaction, the ability to correctly capture the heterogeneity in the saturation state remains critical. Inclusion of a Nernst-Planck term to ensure neutral ionic currents under differential diffusion resulted in at most a 9% correction in upscaled rates.
KAUST Department:
Clean Combustion Research Center
Citation:
Effects of network dissolution changes on pore-to-core upscaled reaction rates for kaolinite and anorthite reactions under acidic conditions 2013, 49 (11):7575 Water Resources Research
Journal:
Water Resources Research
Issue Date:
Nov-2013
DOI:
10.1002/2013WR013667
Type:
Article
ISSN:
00431397
Additional Links:
http://doi.wiley.com/10.1002/2013WR013667
Appears in Collections:
Articles; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorKim, Daesangen
dc.contributor.authorLindquist, W. Brenten
dc.date.accessioned2015-05-03T14:24:48Zen
dc.date.available2015-05-03T14:24:48Zen
dc.date.issued2013-11en
dc.identifier.citationEffects of network dissolution changes on pore-to-core upscaled reaction rates for kaolinite and anorthite reactions under acidic conditions 2013, 49 (11):7575 Water Resources Researchen
dc.identifier.issn00431397en
dc.identifier.doi10.1002/2013WR013667en
dc.identifier.urihttp://hdl.handle.net/10754/552135en
dc.description.abstractWe have extended reactive flow simulation in pore-network models to include geometric changes in the medium from dissolution effects. These effects include changes in pore volume and reactive surface area, as well as topological changes that open new connections. The computed changes were based upon a mineral map from an X-ray computed tomography image of a sandstone core. We studied the effect of these changes on upscaled (pore-scale to core-scale) reaction rates and compared against the predictions of a continuum model. Specifically, we modeled anorthite and kaolinite reactions under acidic flow conditions during which the anorthite reactions remain far from equilibrium (dissolution only), while the kaolinite reactions can be near-equilibrium. Under dissolution changes, core-scale reaction rates continuously and nonlinearly evolved in time. At higher injection rates, agreement with predictions of the continuum model degraded significantly. For the far-from-equilibrium reaction, our results indicate that the ability to correctly capture the heterogeneity in dissolution changes in the reactive mineral surface area is critical to accurately predict upscaled reaction rates. For the near-equilibrium reaction, the ability to correctly capture the heterogeneity in the saturation state remains critical. Inclusion of a Nernst-Planck term to ensure neutral ionic currents under differential diffusion resulted in at most a 9% correction in upscaled rates.en
dc.relation.urlhttp://doi.wiley.com/10.1002/2013WR013667en
dc.rightsArchived with thanks to Water Resources Research. © 2013. American Geophysical Union. All Rights Reserved.http://doi.wiley.com/10.1002/2013WR013667en
dc.titleEffects of network dissolution changes on pore-to-core upscaled reaction rates for kaolinite and anorthite reactions under acidic conditionsen
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.identifier.journalWater Resources Researchen
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionDepartment of Applied Mathematics and Statistics; Stony Brook University; Stony Brook New York USAen
kaust.authorKim, Daesangen
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