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Song-bae Kim - One of the best experts on this subject based on the ideXlab platform.

  • Contaminant Transport and biodegradation in saturated porous media: model development and simulation
    Hydrological Processes, 2005
    Co-Authors: Song-bae Kim
    Abstract:

    A mathematical model is developed to describe the Contaminant Transport, sorption, and biodegradation in saturated porous media. In the model development, sorption was accounted for as a kinetic process for the Contaminant Transport. In addition, a double Monod function was incorporated into the model to describe the biodegradation of Contaminants and utilization of oxygen. In the description of bacterial Transport, reversible and irreversible depositions of bacteria were considered as kinetic processes in the model. The model equations were solved numerically with a fully implicit finite-difference method along with the Runge–Kutta method. The simulation showed that Contaminant Transport in porous media could be greatly affected by sorption and biodegradation processes. Sensitivity analysis demonstrated that the Contaminant Transport model was insensitive to the changes of desorption rate constant for Contaminants kb, half-saturation constant for oxygen Ko, bacterial yield factor Y, and oxygen use coefficient F. However, the model was sensitive to the changes of adsorption rate constant for Contaminants kf, maximum utilization rate of Contaminants µmax, and half-saturation constant for Contaminants Kc, and so their values should be selected carefully in the modelling process. Copyright © 2005 John Wiley & Sons, Ltd.

  • effect of dissolved organic matter and bacteria on Contaminant Transport in riverbank filtration
    Journal of Contaminant Hydrology, 2003
    Co-Authors: Song-bae Kim, Yavuz M Corapcioglu, Dong Ju Kim
    Abstract:

    A mathematical model for the Transport of hydrophobic organic Contaminants in an aquifer under simplistic riverbank filtration conditions is developed. The model considers a situation where Contaminants are present together with dissolved organic matter (DOM) and bacteria. The aquifer is conceptualized as a four-phase system: two mobile colloidal phases, an aqueous phase, and a stationary solid phase. An equilibrium approach is used to describe the interactions of Contaminants with DOM, bacteria, and solid matrix. The model is composed of bacterial Transport equation and Contaminant Transport equation. Numerical simulations are performed to examine the Contaminant Transport behavior in the presence of DOM and bacteria. The simulation results illustrate that Contaminant Transport is enhanced markedly in the presence of DOM and bacteria, and the impact of DOM on Contaminant mobility is greater than that of bacteria under examined conditions. Sensitivity analysis demonstrates that the model is sensitive to changes of three lumped parameters: K1 + (total affinity of stationary solid phase to Contaminants), K2 + (total affinity of DOM to Contaminants), and K3 + (total affinity of bacteria to Contaminants). In a situation where Contaminants exist simultaneously with DOM and bacteria, Contaminant Transport is mainly affected by a ratio of K1 + /K2 + /K3 + , which can vary with changes of equilibrium distribution coefficient of Contaminants and/or colloidal concentrations. In riverbank filtration, the influence of DOM and bacteria on the Transport behavior of Contaminants should be accounted to accurately predict the Contaminant mobility. D 2003 Elsevier Science B.V. All rights reserved.

  • Effect of dissolved organic matter and bacteria on Contaminant Transport in riverbank filtration.
    Journal of contaminant hydrology, 2003
    Co-Authors: Song-bae Kim, M Yavuz Corapcioglu, Dong Ju Kim
    Abstract:

    A mathematical model for the Transport of hydrophobic organic Contaminants in an aquifer under simplistic riverbank filtration conditions is developed. The model considers a situation where Contaminants are present together with dissolved organic matter (DOM) and bacteria. The aquifer is conceptualized as a four-phase system: two mobile colloidal phases, an aqueous phase, and a stationary solid phase. An equilibrium approach is used to describe the interactions of Contaminants with DOM, bacteria, and solid matrix. The model is composed of bacterial Transport equation and Contaminant Transport equation. Numerical simulations are performed to examine the Contaminant Transport behavior in the presence of DOM and bacteria. The simulation results illustrate that Contaminant Transport is enhanced markedly in the presence of DOM and bacteria, and the impact of DOM on Contaminant mobility is greater than that of bacteria under examined conditions. Sensitivity analysis demonstrates that the model is sensitive to changes of three lumped parameters: K+1 (total affinity of stationary solid phase to Contaminants), K+2 (total affinity of DOM to Contaminants), and K+3 (total affinity of bacteria to Contaminants). In a situation where Contaminants exist simultaneously with DOM and bacteria, Contaminant Transport is mainly affected by a ratio of K+1/K+2/K+3, which can vary with changes of equilibrium distribution coefficient of Contaminants and/or colloidal concentrations. In riverbank filtration, the influence of DOM and bacteria on the Transport behavior of Contaminants should be accounted to accurately predict the Contaminant mobility.

Yoshihisa Kawahara - One of the best experts on this subject based on the ideXlab platform.

  • Research on Passive Contaminant Transport in a Vegetated Channel
    Journal of Environmental Informatics, 2016
    Co-Authors: Fatima Jahra, Yoshihisa Kawahara
    Abstract:

    Vegetation plays an important role in the physical, ecological, and hydraulic functions of streams, rivers and many other water bodies and can affect the Transport of water, sediment and nutrients both within the channel and to or between the riparian zones. This research studied the momentum and passive Contaminant Transport mechanism in a vegetated channel with a floodplain (river bank). Three dimensional numerical simulation and physical experimentations were conducted for turbulent flow in the presence of model vegetation. A non-linear k-e model with a vegetation model for turbulent flow and an algebraic flux model proposed by Daly and Harlow (1970) (DH model) for Contaminant Transport were adopted. An in-house code developed by the authors was implemented for numerical simulations. Model vegetation zones were prepared in the channel to predict the mixing mechanism. The numerical results were compared with corresponding experimental observations. A good agreement between the simulated and experimental results was observed in terms of pollutant concentration.

  • Research on Passive Contaminant Transport in a Vegetated Channel
    2014
    Co-Authors: Fatima Jahra, Yoshihisa Kawahara
    Abstract:

    Vegetation plays an important role in the physical, ecological, and hydraulic functions of streams, rivers and many other water bodies and can affect the Transport of water, sediment and nutrients both within the channel and to or between the riparian zones. This research studied the momentum and passive Contaminant Transport mechanism in a vegetated channel with a floodplain. Three dimensional numerical simulation and physical experimentations were conducted for turbulent flow in the presence of model vegetation. A non-linear k-e model with a vegetation model for turbulent flow and an algebraic flux model (DH model) for Contaminant Transport were adopted. An in-house code developed by the authors was implemented for numerical simulations. Model vegetation zones were prepared in the channel to predict the mixing mechanism. The numerical results were compared with corresponding experimental observations. A good agreement between the simulated and experimental results was observed in terms of pollutant concentration.

Dong Ju Kim - One of the best experts on this subject based on the ideXlab platform.

  • effect of dissolved organic matter and bacteria on Contaminant Transport in riverbank filtration
    Journal of Contaminant Hydrology, 2003
    Co-Authors: Song-bae Kim, Yavuz M Corapcioglu, Dong Ju Kim
    Abstract:

    A mathematical model for the Transport of hydrophobic organic Contaminants in an aquifer under simplistic riverbank filtration conditions is developed. The model considers a situation where Contaminants are present together with dissolved organic matter (DOM) and bacteria. The aquifer is conceptualized as a four-phase system: two mobile colloidal phases, an aqueous phase, and a stationary solid phase. An equilibrium approach is used to describe the interactions of Contaminants with DOM, bacteria, and solid matrix. The model is composed of bacterial Transport equation and Contaminant Transport equation. Numerical simulations are performed to examine the Contaminant Transport behavior in the presence of DOM and bacteria. The simulation results illustrate that Contaminant Transport is enhanced markedly in the presence of DOM and bacteria, and the impact of DOM on Contaminant mobility is greater than that of bacteria under examined conditions. Sensitivity analysis demonstrates that the model is sensitive to changes of three lumped parameters: K1 + (total affinity of stationary solid phase to Contaminants), K2 + (total affinity of DOM to Contaminants), and K3 + (total affinity of bacteria to Contaminants). In a situation where Contaminants exist simultaneously with DOM and bacteria, Contaminant Transport is mainly affected by a ratio of K1 + /K2 + /K3 + , which can vary with changes of equilibrium distribution coefficient of Contaminants and/or colloidal concentrations. In riverbank filtration, the influence of DOM and bacteria on the Transport behavior of Contaminants should be accounted to accurately predict the Contaminant mobility. D 2003 Elsevier Science B.V. All rights reserved.

  • Effect of dissolved organic matter and bacteria on Contaminant Transport in riverbank filtration.
    Journal of contaminant hydrology, 2003
    Co-Authors: Song-bae Kim, M Yavuz Corapcioglu, Dong Ju Kim
    Abstract:

    A mathematical model for the Transport of hydrophobic organic Contaminants in an aquifer under simplistic riverbank filtration conditions is developed. The model considers a situation where Contaminants are present together with dissolved organic matter (DOM) and bacteria. The aquifer is conceptualized as a four-phase system: two mobile colloidal phases, an aqueous phase, and a stationary solid phase. An equilibrium approach is used to describe the interactions of Contaminants with DOM, bacteria, and solid matrix. The model is composed of bacterial Transport equation and Contaminant Transport equation. Numerical simulations are performed to examine the Contaminant Transport behavior in the presence of DOM and bacteria. The simulation results illustrate that Contaminant Transport is enhanced markedly in the presence of DOM and bacteria, and the impact of DOM on Contaminant mobility is greater than that of bacteria under examined conditions. Sensitivity analysis demonstrates that the model is sensitive to changes of three lumped parameters: K+1 (total affinity of stationary solid phase to Contaminants), K+2 (total affinity of DOM to Contaminants), and K+3 (total affinity of bacteria to Contaminants). In a situation where Contaminants exist simultaneously with DOM and bacteria, Contaminant Transport is mainly affected by a ratio of K+1/K+2/K+3, which can vary with changes of equilibrium distribution coefficient of Contaminants and/or colloidal concentrations. In riverbank filtration, the influence of DOM and bacteria on the Transport behavior of Contaminants should be accounted to accurately predict the Contaminant mobility.

Kartic C. Khilar - One of the best experts on this subject based on the ideXlab platform.

  • Review on subsurface colloids and colloid-associated Contaminant Transport in saturated porous media.
    Advances in colloid and interface science, 2005
    Co-Authors: Tushar Kanti Sen, Kartic C. Khilar
    Abstract:

    In this review article, the authors present up-to-date developments on experimental, modeling and field studies on the role of subsurface colloidal fines on Contaminant Transport in saturated porous media. It is a complex phenomenon in porous media involving several basic processes such as colloidal fines release, dispersion stabilization, migration and fines entrapment/plugging at the pore constrictions and adsorption at solid/liquid interface. The effects of these basic processes on the Contaminant Transport have been compiled. Here the authors first present the compilation on in situ colloidal fines sources, release, stabilization of colloidal dispersion and migration which are a function of physical and chemical conditions of subsurface environment and finally their role in inorganic and organic Contaminants Transport in porous media. The important aspects of this article are as follows: (i) it gives not only complete compilation on colloidal fines-facilitated Contaminant Transport but also reviews the new role of colloidal fines in Contaminant retardation due to plugging of pore constrictions. This plugging phenomenon also depends on various factors such as concentration of colloidal fines, superficial velocity and bead-to-particle size ratio. This plugging-based Contaminant Transport can be used to develop containment technique in soil and groundwater remediation. (ii) It also presents the importance of critical salt concentration (CSC), critical ionic strength for mixed salt, critical shear stressor critical particle concentration (CPC) on in situ colloidal fines release and migration and consequently their role on Contaminant Transport in porous media. (iii) It also reviews another class of colloidal fines called biocolloids and their Transport in porous media. Finally, the authors highlight the future research based on their critical review on colloid-associated Contaminant Transport in saturated porous media.

  • Colloid‐associated Contaminant Transport in porous media: 2. Mathematical modeling
    AIChE Journal, 2002
    Co-Authors: Tushar Kanti Sen, Nitesh Nalwaya, Kartic C. Khilar
    Abstract:

    A comprehensive mathematical model developed describes the colloid-associated Contaminant Transport in groundwater flows based on equilibrium adsorption of Contaminants, hydrodynamic release, migration, and capture of colloidal fines in groundwater flows. This model is more realistic than the existing models in that the physics of migration of colloidal fines is adequately incorporated. It also accounts for the entrapment and plugging of fine particles and, therefore, predicts both facilitation and retardation of the Transport of Contaminants depending on the flow and other conditions. The conditions leading to inhibition/retardation of Contaminant Transport due to plugging are: high release coefficient, low initial porosity, high inlet fines concentration, and high initial permeability. The mobilization and migration of colloidal fines, kaolin and their role on plugging, as well as on Ni2+ Contaminant Transport through kaolin-sand packed beds, were studied, and the model was tested with published experimental measurements, as well as with our laboratory column results. The plugging-based retardation of Contaminant Transport can be used to develop a new containment technique.

Fatima Jahra - One of the best experts on this subject based on the ideXlab platform.

  • Research on Passive Contaminant Transport in a Vegetated Channel
    Journal of Environmental Informatics, 2016
    Co-Authors: Fatima Jahra, Yoshihisa Kawahara
    Abstract:

    Vegetation plays an important role in the physical, ecological, and hydraulic functions of streams, rivers and many other water bodies and can affect the Transport of water, sediment and nutrients both within the channel and to or between the riparian zones. This research studied the momentum and passive Contaminant Transport mechanism in a vegetated channel with a floodplain (river bank). Three dimensional numerical simulation and physical experimentations were conducted for turbulent flow in the presence of model vegetation. A non-linear k-e model with a vegetation model for turbulent flow and an algebraic flux model proposed by Daly and Harlow (1970) (DH model) for Contaminant Transport were adopted. An in-house code developed by the authors was implemented for numerical simulations. Model vegetation zones were prepared in the channel to predict the mixing mechanism. The numerical results were compared with corresponding experimental observations. A good agreement between the simulated and experimental results was observed in terms of pollutant concentration.

  • Research on Passive Contaminant Transport in a Vegetated Channel
    2014
    Co-Authors: Fatima Jahra, Yoshihisa Kawahara
    Abstract:

    Vegetation plays an important role in the physical, ecological, and hydraulic functions of streams, rivers and many other water bodies and can affect the Transport of water, sediment and nutrients both within the channel and to or between the riparian zones. This research studied the momentum and passive Contaminant Transport mechanism in a vegetated channel with a floodplain. Three dimensional numerical simulation and physical experimentations were conducted for turbulent flow in the presence of model vegetation. A non-linear k-e model with a vegetation model for turbulent flow and an algebraic flux model (DH model) for Contaminant Transport were adopted. An in-house code developed by the authors was implemented for numerical simulations. Model vegetation zones were prepared in the channel to predict the mixing mechanism. The numerical results were compared with corresponding experimental observations. A good agreement between the simulated and experimental results was observed in terms of pollutant concentration.