A reactionbased paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions
Abstract
This paper presents a reactionbased water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M partial differential equations (PDEs). Decomposition via GaussJordan column reduction of the reaction network transforms M species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing NE equilibrium reactions and a set of reactive transport equations of MNE kineticvariables involving no equilibrium reactions (a kineticvariable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kineticvariables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kineticmore »
 Authors:
 ORNL
 University of Central Florida, Orlando
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC)
 OSTI Identifier:
 931723
 DOE Contract Number:
 DEAC0500OR22725
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Contaminant Hydrology; Journal Volume: 92; Journal Issue: 12
 Country of Publication:
 United States
 Language:
 English
 Subject:
 54 ENVIRONMENTAL SCIENCES; 97; KINETIC EQUATIONS; PARTIAL DIFFERENTIAL EQUATIONS; ENVIRONMENTAL TRANSPORT; WATER QUALITY; GROUND WATER; CHEMICAL REACTIONS; EQUILIBRIUM; MATHEMATICAL MODELS; URANIUM; SOILS; RADIONUCLIDE MIGRATION
Citation Formats
Zhang, Fan, Yeh, GourTsyh, Parker, Jack C, Brooks, Scott C, Pace, Molly, Kim, Young Jin, Jardine, Philip M, and Watson, David B. A reactionbased paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions. United States: N. p., 2007.
Web. doi:10.1016/j.jconhyd.2006.11.007.
Zhang, Fan, Yeh, GourTsyh, Parker, Jack C, Brooks, Scott C, Pace, Molly, Kim, Young Jin, Jardine, Philip M, & Watson, David B. A reactionbased paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions. United States. doi:10.1016/j.jconhyd.2006.11.007.
Zhang, Fan, Yeh, GourTsyh, Parker, Jack C, Brooks, Scott C, Pace, Molly, Kim, Young Jin, Jardine, Philip M, and Watson, David B. Mon .
"A reactionbased paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions". United States.
doi:10.1016/j.jconhyd.2006.11.007.
@article{osti_931723,
title = {A reactionbased paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions},
author = {Zhang, Fan and Yeh, GourTsyh and Parker, Jack C and Brooks, Scott C and Pace, Molly and Kim, Young Jin and Jardine, Philip M and Watson, David B},
abstractNote = {This paper presents a reactionbased water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M partial differential equations (PDEs). Decomposition via GaussJordan column reduction of the reaction network transforms M species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing NE equilibrium reactions and a set of reactive transport equations of MNE kineticvariables involving no equilibrium reactions (a kineticvariable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kineticvariables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kinetic and equilibrium reactions.},
doi = {10.1016/j.jconhyd.2006.11.007},
journal = {Journal of Contaminant Hydrology},
number = 12,
volume = 92,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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