Detachment-Influenced Transport of an Adhesion-Deficient Bacterial Strain within Water-Reactive Porous Media

Abstract

Bacteria and carboxylate-modified microsphere transport experiments were performed in glass bead packed columns in order to examine the distribution of retained colloids on the sediment. Solution pH was allowed to vary from 6.0 to 9.4 across the length of the column (20 cm) in order to examine potential effects of solution chemistry on the retained profiles. Both the microspheres and the bacteria showed retained profiles that deviated strongly from log-linear behavior expected from a spatially invariant colloid deposition rate coefficient. Deviation for the microspheres was in the form of steeper-than-expected decreases in retained concentrations with distance from source. Deviation for the bacteria was in the form of maximum retained concentrations that were located down-gradient from the column inlet. Subsidiary experiments with varying elution times showed that detachment during elution moved the peak of mass of retained bacteria down-gradient of the column inlet; however, the disproportional translation of the peak of mass relative to elution time indicated that processes operating during injection produced the initial down-gradient translation of peak concentrations of retained cells.

Transport of E. coli in aquifer sediments of Bangladesh: Implications for widespread microbial contamination of groundwater

“…In a separate study, Foppen et al [2007b] used a dual deposition mode approach for E. coli attachment with deionized water in washed quartz sand to fit profiles for strained and adsorbed bacteria separately, finding a reversible attachment rate between 3 and 22 hr -1 and an irreversible rate between 25 and 350 hr -1 . Tong and coworkers applied a random-walk particle tracking model to transport of an adhesion-deficient bacterial strain in soda-lime glass beads, finding attachment rates between 0.2 and 1.6 hr -1 and detachment rates between 0.05 and 0.25 hr -1 [ Tong et al , 2005]. These rates are comparable to all of the low-ionic strength experiments in the current study, where the average detachment rate was 0.5 hr -1 .…”

Predicting colloid transport through saturated porous media: A critical review

“…Extended tailing may occur during the elution phase of unfavorable experiments (Figure 2, left and middle top row). Tailing is defined by the slow release of colloids from the column (illustrated in Figure 2) and is indicative of significant reentrainment, as observed for microbes in the laboratory [Fontes et al, 1991;Hornberger et al, 1992;Lindqvist et al, 1994;McCaulou et al, 1994;Johnson et al, 1995b;McCaulou et al, 1995;Hendry et al, 1997Hendry et al, , 1999Harter et al, 2000;, field [Scholl and Harvey, 1992;Harvey et al, 1995;DeBorde et al, 1999;Ryan et al, 1999;Schijven et al, 1999], and nonbiological colloids [Li et al, 2004;Tufenkji et al, 2004;Tong et al, 2005;Johnson et al, 2007b]. The reentrainment behavior under unfavorable conditions is sensitive to solution chemistry and fluid flow as shown for reentrainment with perturbations, including variation in ionic strength [Ryan et al, 1999;Tufenkji andElimelech, 2004a, 2005a;Shen et al, 2007;Mattison et al, 2011;Jiang et al, 2012a;Shen et al, 2012], variation in pH [Ryan et al, 1999;Tufenkji andElimelech, 2004a, 2005a], and variation in fluid velocity [Shang et al, 2008;Pazmino et al, 2014a].…”

Cotransport of Pseudomonas putida and kaolinite particles through water‐saturated columns packed with glass beads

“…[19] Following the procedure outlined by Tong et al [2005], the glass beads were first rinsed sequentially with acetone and hexane and then soaked in concentrated HCl for about 12 h. Next, the beads were rinsed with ddH 2 O until the water conductivity, as determined by a conductivity meter, was negligible. Subsequently, the glass beads were soaked in 0.1 M NaOH for 12 h and rinsed repeatedly with ddH 2 O until the ionic strength (IS) of water was negligible.…”

“…A decrease in ionic strength results in electrical double‐layer expansion, and an increase in pH enlarges the negative charge on colloid surfaces. These solution chemistry changes increase the repulsive forces between suspended particles and collector surfaces and, consequently, may enhance the release of deposited particles [ Tong et al , 2005; Shiratori et al , 2007].…”