Bacterial Deposition in Porous Media:  Effects of Cell-Coating, Substratum Hydrophobicity, and Electrolyte Concentration

Abstract

Deposition of seven bacterial strains on spherical glass and Teflon collectors was studied in vertical downflow columns at an ionic strength (I) of 0.1 M. The various bacteria had either one of the following types of major cell-surface constituents: nonpolysaccharide (NP), amphiphilic (AMPH), or anionic polysaccharide (AP) macromolecules. Deposition was analyzed in terms of the clean bed collision efficiency R 0 (the probability of a cell to attach upon reaching a substratum free of cells) and a blocking factor B (the ratio of the area blocked by an attached cell to the geometric area of a cell). The value of R 0 decreased from 1.0 to about 0.01 in the following order of cell-surface constituents/collector combinations: NP/Teflon and AMPH/Teflon > NP/glass > AMPH/ glass, AP/Teflon, and AP/glass. The value for B, at a Peclet number of 1 × 10 5 , increased from about 3 to 18 in the order NP/low cell charge < NP or AMPH/ high cell charge < AP/high cell charge. This indicates that cell-cell repulsion enhances blocking. Blocking is higher on Teflon than on glass. Most likely cell-surface macromolecules adsorb in the surroundings of the attached cells and enhance blocking on Teflon. The deposition of four bacterial strains was investigated at 0.0001 M e I e 0.1 M. For I values smaller than a critical level, R 0 decreased with decreasing I. The critical I is determined by the range over which cell-surface macromolecules can penetrate the repulsive Gibbs energy barrier between cell and solid. The value for B increases about 1 order of magnitude upon changing I from 0.1 to 0.001 M. Maximal control of microbial mobility in porous media can be reached in systems for which B and R 0 are high at high I (0.1 M): the high B value minimizes the occurrence of pore-clogging whereas the dependencies of R 0 and B on I allow manipulation of deposition by varying the ionic strength.

Development of Permeable Reactive Barriers (PRB) Using Edible Oils

“…The α' values for FS-7% and FS-9% are similar to values obtained for common bacteria (Camesano and Logan 1998, Camesano et al 1999, Rijnaarts et al 1996a. Similarly, the variability α' is comparable to that observed for bacteria retention by other investigators (Jewett et al 1995).…”

“…The single collector efficiency is most commonly determined using the Rajagopalan and Tien equation (1976) which includes terms for diffusion (η D ), interception (η I ) and gravitational settling (η S ). α is an empirical term that reflects a variety of particle -collector interactions that affect adhesion including pH, ion strength, colloid and sand grain surface coatings, and prior coverage of the collector surface by previously trapped particles (Rijnaarts et al 1996a, Bolster et al 2001.…”

Solid mechanics in colloidal and bacterial filtration

“…These studies revealed new factors affecting colloidal or bacterial filtration, e.g. bacterial surface characterizations (Abu-Lail & Camesano, 2003;Burks et al, 2003;Kuznar & Elimelech, 2005;Rijnaarts, Norde, Bouwer, Lyklema, & Zehnder, 1995, 1996bRijnaarts, Norde, Lyklema, & Zehnder, 1999;Williams & Fletcher, 1996), motility (Matthew W Becker, Samantha A Collins, David W Metge, Ronald W Harvey, & Allen M Shapiro, 2004;Camesano & Logan, 1998;Camper, Hayes, Sturman, Jones, & Cunningham, 1993;Hendry, Lawrence, & Maloszewski, 1999;McCaulou, Bales, & Arnold, 1995), softness (Ivanov, 2012;Y. Li, Wang, Onnis-Hayden, Wan, & Gu, 2014;X.…”

“…For bacteria with motility, low flow velocity has limited impacts (Grolimund et al, 1998). Fluid velocity also affects bacteria collision with collector via the blocking effect (Rijnaarts, Norde, Bouwer, Lyklema, & Zehnder, 1996a;Rijnaarts et al, 1996b). Under low flow rate, a bacterium has smaller hydrodynamic shadow and diffuses faster.…”

“…Recent studies which attempted to improve our understanding on the role of such macromolecules in microbial adhesion, showed that the presence of surface biomolecules can either enhance (Abu-Lail & Camesano, 2003;Burks et al, 2003;Rijnaarts et al, 1995Rijnaarts et al, , 1996bRijnaarts et al, 1999;Walker et al, 2004) or hinder (Burks et al, 2003;Kuznar & Elimelech, 2005;Rijnaarts et al, 1995Rijnaarts et al, , 1996bRijnaarts et al, 1999;Williams & Fletcher, 1996) microbe adhesion in aqueous media. Correlation of transport/adhesion behavior of E Coli (K12 mutant JM109, Abu-Lail and Camesano) and LPS on cell wall is still not clear (Burks et al, 2003;Walker et al, 2004).…”