TY - JOUR
T1 - Monitoring bacterially induced calcite precipitation in porous media using magnetic resonance imaging and flow measurements
AU - Sham, E.
AU - Mantle, M.D.
AU - Mitchell, J.B.A.
AU - Tobler, D.J.
AU - Phoenix, V.R.
AU - Johns, Michael
PY - 2013
Y1 - 2013
N2 - A range of nuclear magnetic resonance (NMR) techniques are employed to provide novel, non-invasive measurements of both the structure and transport properties of porous media following a biologically mediated calcite precipitation reaction. Both a model glass bead pack and a sandstone rock core were considered. Structure was probed using magnetic resonance imaging (MRI) via a combination of quantitative one-dimensional profiles and three-dimensional images, applied before and after the formation of calcite in order to characterise the spatial distribution of the precipitate. It was shown through modification and variations of the calcite precipitation treatment that differences in the calcite fill would occur but all methods were successful in partially blocking the different porous media. Precipitation was seen to occur predominantly at the inlet of the bead pack, whereas precipitation occurred almost uniformly along the sandstone core. Transport properties are quantified using pulse field gradient (PFG) NMR measurements which provide probability distributions of molecular displacement over a set observation time (propagators), supplementing conventional permeability measurements. Propagators quantify the local effect of calcite formation on system hydrodynamics and the extent of stagnant region formation. Collectively, the combination of NMR measurements utilised here provides a toolkit for determining the efficacy of a biological-precipitation reaction for partially blocking porous materials. © 2013 Elsevier B.V.
AB - A range of nuclear magnetic resonance (NMR) techniques are employed to provide novel, non-invasive measurements of both the structure and transport properties of porous media following a biologically mediated calcite precipitation reaction. Both a model glass bead pack and a sandstone rock core were considered. Structure was probed using magnetic resonance imaging (MRI) via a combination of quantitative one-dimensional profiles and three-dimensional images, applied before and after the formation of calcite in order to characterise the spatial distribution of the precipitate. It was shown through modification and variations of the calcite precipitation treatment that differences in the calcite fill would occur but all methods were successful in partially blocking the different porous media. Precipitation was seen to occur predominantly at the inlet of the bead pack, whereas precipitation occurred almost uniformly along the sandstone core. Transport properties are quantified using pulse field gradient (PFG) NMR measurements which provide probability distributions of molecular displacement over a set observation time (propagators), supplementing conventional permeability measurements. Propagators quantify the local effect of calcite formation on system hydrodynamics and the extent of stagnant region formation. Collectively, the combination of NMR measurements utilised here provides a toolkit for determining the efficacy of a biological-precipitation reaction for partially blocking porous materials. © 2013 Elsevier B.V.
U2 - 10.1016/j.jconhyd.2013.06.003
DO - 10.1016/j.jconhyd.2013.06.003
M3 - Article
C2 - 23872026
SN - 0169-7722
VL - 152
SP - 35
EP - 43
JO - Journal of Contaminant Hydrology
JF - Journal of Contaminant Hydrology
ER -