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Title: Modeling biofiltration of gas streams containing TEX components

Abstract

This paper describes a phenomenological model for simulating the removal of toluene, ethylbenzene and o-xylene (TEX) from contaminated air streams by a biofilter. The phenomena incorporated into the model are interphase mass transfer between the gas and the aqueous biofilm with equilibrium partition, advection, diffusion, and biological reactions. The reaction rate for each TEX component is quantified using a more generalized Monod equation to allow for inhibitive effects in the presence of multiple substrates. Solutions to the system of coupled nonlinear partial differential equations representing component mass conservation are obtained by a fully implicit finite difference method with first-order accuracy in time and second-order accuracy in space. A parametric study is performed to evaluate the sensitivity of the Peclet number and the normalized mass transfer coefficient, both of which show strong influence on the removal rates. Comparison of the concentration distribution along the biofilter against available measured data and the exact closed-form solution indicates a good agreement with discrepancies being within experimental uncertainties.

Authors:
;  [1]; ;  [2]
  1. Idaho National Engineering and Environmental Lab., Idaho Falls, ID (United States)
  2. Idaho State Univ., Pocatella, ID (United States). Coll. of Engineering
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
509263
DOE Contract Number:
AC07-94ID13223
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Environmental Engineering; Journal Volume: 123; Journal Issue: 6; Other Information: PBD: Jun 1997
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 02 PETROLEUM; ALKYLATED AROMATICS; BIODEGRADATION; MATHEMATICAL MODELS; BIOREACTORS; AIR POLLUTION ABATEMENT; GROUND WATER; REMEDIAL ACTION; OIL SPILLS

Citation Formats

Nguyen, H.D., Douglass, R.W., Sato, C., and Wu, J. Modeling biofiltration of gas streams containing TEX components. United States: N. p., 1997. Web. doi:10.1061/(ASCE)0733-9372(1997)123:6(615).
Nguyen, H.D., Douglass, R.W., Sato, C., & Wu, J. Modeling biofiltration of gas streams containing TEX components. United States. doi:10.1061/(ASCE)0733-9372(1997)123:6(615).
Nguyen, H.D., Douglass, R.W., Sato, C., and Wu, J. 1997. "Modeling biofiltration of gas streams containing TEX components". United States. doi:10.1061/(ASCE)0733-9372(1997)123:6(615).
@article{osti_509263,
title = {Modeling biofiltration of gas streams containing TEX components},
author = {Nguyen, H.D. and Douglass, R.W. and Sato, C. and Wu, J.},
abstractNote = {This paper describes a phenomenological model for simulating the removal of toluene, ethylbenzene and o-xylene (TEX) from contaminated air streams by a biofilter. The phenomena incorporated into the model are interphase mass transfer between the gas and the aqueous biofilm with equilibrium partition, advection, diffusion, and biological reactions. The reaction rate for each TEX component is quantified using a more generalized Monod equation to allow for inhibitive effects in the presence of multiple substrates. Solutions to the system of coupled nonlinear partial differential equations representing component mass conservation are obtained by a fully implicit finite difference method with first-order accuracy in time and second-order accuracy in space. A parametric study is performed to evaluate the sensitivity of the Peclet number and the normalized mass transfer coefficient, both of which show strong influence on the removal rates. Comparison of the concentration distribution along the biofilter against available measured data and the exact closed-form solution indicates a good agreement with discrepancies being within experimental uncertainties.},
doi = {10.1061/(ASCE)0733-9372(1997)123:6(615)},
journal = {Journal of Environmental Engineering},
number = 6,
volume = 123,
place = {United States},
year = 1997,
month = 6
}
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