Title

Effect of Permeable Biofilm on Micro-and Macro-Scale Flow and Transport in Bioclogged Pores

Abstract

Simulations of coupled flow around and inside biofilms in pores were conducted to study the effect of porous biofilm on micro-and macro-scale flow and transport. The simulations solved the Navier-Stokes equations coupled with the Brinkman equation representing flow in the pore space and biofilm, respectively, and the advection-diffusion equation. Biofilm structure and distribution were obtained from confocal microscope images. The bulk permeability (k) of bioclogged porous media depends on biofilm permeability (kbr) following a sigmoidal curve on a log-log scale. The upper and lower limits of the curve are the k of biofilm-free media and of bioclogged media with impermeable biofilms, respectively. On the basis of this, a model is developed that predicts k based solely on kbr and biofilm volume ratio. The simulations show that kbr has a significant impact on the shear stress distribution, and thus potentially affects biofilm erosion and detachment. The sensitivity of flow fields to kbr directly translated to effects on the transport fields by affecting the relative distribution of where advection and diffusion dominated. Both kbr and biofilm volume ratio affect the shape of breakthrough curves.

Department(s)

Civil, Architectural and Environmental Engineering

Comments

This material is based upon work supported as part of the Center for Frontiers of Subsurface Energy Security (CFSES), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award No. DE-SC0001114. Matching funding was provided by the Geology Foundation of the University of Texas.

Keywords and Phrases

Advection and diffusions; Advection-diffusion equation; Biofilm permeabilities; Biofilm structure; Break through curve; Brinkman equation; Confocal microscope images; Flow and transport; Advection; Navier Stokes equations; Porous materials; Biofilms; Breakthrough curve; Navier-Stokes equations; Numerical model; Permeability; Pore space; Porous medium; Shear stress; Article; Bioclogging; Confocal microscopy; Controlled study; Diffusion; Membrane permeability; Membrane structure; Membrane transport; Prediction; Simulation; Transport kinetics; Models; Theoretical; Porosity; Pseudomonas fluorescens

International Standard Serial Number (ISSN)

0013-936X; 1520-5851

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2013 American Chemical Society (ACS), All rights reserved.

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