TY - JOUR
T1 - Transport of Sporosarcina pasteurii in sandstone and its significance for subsurface engineering technologies
AU - Tobler, Dominique Jeanette
AU - Cuthbert, Mark O.
AU - Phoenix, Vernon R.
PY - 2014
Y1 - 2014
N2 - The development of microbially mediated technologies for subsurface remediation and rock engineering is steadily increasing; however, we are lacking experimental data and models to predict bacterial movement through rock matrices. Here, breakthrough curves (BTCs) were obtained to quantify the transport of the ureolytic bacterium, Sporosarcina pasteurii, through sandstone cores, as a function of core length (1.8-7.5cm), bacterial density (4×106 to 9×107cells/ml) and flow rate (5.8-17.5m/s). S. pasteurii was easily immobilised within the homogeneous sandstone matrix (>80%) in comparison to a packed sand column (<20%; under similar experimental conditions), and percentage recovery decreased almost linearly with increasing rock core length. Moreover, a decrease in bacterial density or flow rate enhanced bacterial retention. A numerical model based on 1D advection dispersion models used for unconsolidated sand was fitted to the BTC data obtained here for sandstone. Good agreement between data and model was obtained at shorter rock core lengths (<4cm), suggesting that physicochemical filtration processes are similar in homogeneous packed sand and sandstones at these lengths. Discrepancies were, however observed at longer core lengths and with varying flow rates, indicating that the attributes of consolidated rock might impact bacterial transport progressively more with increasing core length. Implications of these results on microbial mineralisation technologies currently being developed for sealing fluid paths in subsurface environment is discussed.
AB - The development of microbially mediated technologies for subsurface remediation and rock engineering is steadily increasing; however, we are lacking experimental data and models to predict bacterial movement through rock matrices. Here, breakthrough curves (BTCs) were obtained to quantify the transport of the ureolytic bacterium, Sporosarcina pasteurii, through sandstone cores, as a function of core length (1.8-7.5cm), bacterial density (4×106 to 9×107cells/ml) and flow rate (5.8-17.5m/s). S. pasteurii was easily immobilised within the homogeneous sandstone matrix (>80%) in comparison to a packed sand column (<20%; under similar experimental conditions), and percentage recovery decreased almost linearly with increasing rock core length. Moreover, a decrease in bacterial density or flow rate enhanced bacterial retention. A numerical model based on 1D advection dispersion models used for unconsolidated sand was fitted to the BTC data obtained here for sandstone. Good agreement between data and model was obtained at shorter rock core lengths (<4cm), suggesting that physicochemical filtration processes are similar in homogeneous packed sand and sandstones at these lengths. Discrepancies were, however observed at longer core lengths and with varying flow rates, indicating that the attributes of consolidated rock might impact bacterial transport progressively more with increasing core length. Implications of these results on microbial mineralisation technologies currently being developed for sealing fluid paths in subsurface environment is discussed.
U2 - 10.1016/j.apgeochem.2014.01.004
DO - 10.1016/j.apgeochem.2014.01.004
M3 - Journal article
AN - SCOPUS:84893388478
SN - 0883-2927
VL - 42
SP - 38
EP - 44
JO - Applied Geochemistry
JF - Applied Geochemistry
ER -