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David Saloner - One of the best experts on this subject based on the ideXlab platform.

Petter Dyverfeldt - One of the best experts on this subject based on the ideXlab platform.

Michael D Hope - One of the best experts on this subject based on the ideXlab platform.

Elaine E Tseng - One of the best experts on this subject based on the ideXlab platform.

Michael L Johns - One of the best experts on this subject based on the ideXlab platform.

  • Novel Magnetic Resonance Measurements of Fouling in Operating Spiral Wound Reverse Osmosis Membrane Modules.
    Water research, 2021
    Co-Authors: Nicholas W. Bristow, Michael L Johns, Sarah J. Vogt, Szilard Bucs, Johannes S. Vrouwenvelder, Einar O. Fridjonsson
    Abstract:

    Abstract A novel Magnetic Resonance Measurement (MRM) protocol for non-invasive monitoring of fouling in spiral wound reverse osmosis (SWRO) membrane modules is demonstrated. Sodium alginate was used to progressively foul a commercial SWRO membrane at industrially relevant operating conditions in a circulating flow loop. The MRM protocol showcased the following: (i) earlier, more sensitive detection and quantification of fouling in the membrane module compared to feed-channel pressure drop. This was achieved using appropriate detection of the total nuclear Magnetic Resonance (NMR) signal. (ii) 2D cross-sectional imaging of the location of the accumulated foulant material; this was preferentially located adjacent to the membrane spacer sheet nodes, which was subsequently confirmed by a module autopsy. This image contrast, which could also readily differentiate the membrane, feed spacer and permeate spacer regions, was realised based on differences in the NMR relaxation parameter, T2,eff. (iii) High frequency acquisition of 2D cross-sectional velocity images of the module revealing very localised flow channelling in response to gradual foulant accumulation which impacted significantly on the flow pattern within the central permeate tube. Collectively this NMR/MRI Measurement protocol provides a powerful analysis tool for the evolution of fouling in such complex modules, thus ultimately enabling more informed module design.

  • monitoring water transport in sandstone using flow propagators a quantitative comparison of nuclear Magnetic Resonance Measurement with lattice boltzmann and pore network simulations
    Advances in Water Resources, 2013
    Co-Authors: R Hussain, P S Hammond, Andrew J. Sederman, J. Mitchell, Michael L Johns
    Abstract:

    Abstract A comparison of advective displacement probability distributions (flow propagators) obtained by nuclear Magnetic Resonance (NMR) experiment with both lattice Boltzmann (LB) and pore network (PN) simulations is presented. Here, we apply all three methods to the exact same sample for the first time: we consider water transport in a Bentheimer sandstone. The LB and PN simulations are based on X-ray micro-tomography (XMT) images of a small rock sample; the NMR experiments are conducted on a much larger rock core-plug from which the small rock sample originated. Despite the limited size of the simulation domains, good agreement is achieved between all three sets of results, verified quantitatively by comparison of the low order moments of the flow propagators. We are concerned primarily with validating the simulations at high liquid flow rates (>10 ml min−1) in high permeability sandstone, ultimately for future application to geological carbon sequestration studies. Under these conditions the LB simulation is found, as expected, to be more robust than the PN model due primarily to the reduced requirement to manually tune the simulation lattice to match the petro-physical properties of the rock.