HR: 0830h
AN: H51A-04    [Abstracts]
TI: Modeling the Effects of Mass Transfer on Contaminant Biodegradation in Porous Media
AU: * Mendoza-Sanchez, I
EM: itzam@neo.tamu.edu
AF: Texas A&M University, Department of Civil Engineering, Environmental and Water Resources Division, 3136 TAMU , College Station, TX 77843-3136 United States
AU: Cunningham, J A
EM: cunning@eng.usf.edu
AF: University of South Florida, Dept. of Civil & Environmental Engineering, 4202 E. Fowler Ave., ENB 118, Tampa, FL 33620 United States
AB: The effect of mass transfer on the rate of contaminant biodegradation in porous media has been evaluated using a mathematical model that accounts for the mechanisms of mass transport in the bulk liquid by advection and dispersion, mass transfer from the bulk liquid to the biofilm (BF) by diffusion, molecular diffusion within the BF, and biological reaction within the BF. The resulting set of equations has been solved using a finite difference method with operator splitting and an iterative solution procedure. The mathematical model was applied to a hypothetical column of homogeneous grains. The main result is that mass transfer may be a limiting factor in the rate of biodegradation. Mass transfer is strongly related to characteristics of the porous medium, namely porosity, hydraulic conductivity, water flow velocity, grain size distribution, contaminant characteristics, and biofilm characteristics. Therefore, the results presented here represent a first step to improve our understanding of biodegradation in biological reactors or during groundwater bioremediation, and, consequently, to enable the design of more effective treatment technologies.
DE: 1829 Groundwater hydrology
DE: 1832 Groundwater transport
SC: Hydrology [H]
MN: 2005 Joint Assembly