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A.b. Mersmann - One of the best experts on this subject based on the ideXlab platform.

  • On intraparticle Total Pressure Change during gas phase adsorption
    Gas Separation & Purification, 1991
    Co-Authors: S.e. Scholl, A.b. Mersmann
    Abstract:

    Abstract The effect of a non-constant intraparticle Total Pressure for one-component ad- and desorption kinetics on single adsorbent pellets is investigated. Intraparticle pore mass transport is quantified by using the Dusty Gas model accounting for Knudsen diffusion, Fickian diffusion and viscous flow. Sorbed phase diffusion may also be included. Adsorption equilibrium between pore fluid and adsorbed phase is assumed. From the computations intraparticle Total Pressure, temperature and concentration profiles are obtained. It is found that intraparticle Total Pressure Change may be as high as 1% of the ambient Total Pressure depending on process conditions as well as material properties. Although this results in a viscous flow contribution to Total pore mass transport of up to 15% at certain positions within the particle, the effect seems negligible for most cases of practical relevance as far as purification tasks are considered. For separation purposes further studies are needed.

  • Influence of intraparticle Total Pressure Change on pore mass transport
    Chemical Engineering & Technology, 1991
    Co-Authors: Stephan Scholl, A.b. Mersmann
    Abstract:

    Influence of intraparticle Total Pressure Change on pore mass transport is investigated in physical gas phase adsorption of a single component from an inert carrier medium. The Dusty Gas Model is applied to quantify pore mass transport, assuming local equilibrium between pore fluid and adsorbed phase. Calculated results for single pellet adsorption kinetics of cyclohexane on activated carbon and CO2 on molecular sieve 5 A are compared with experimental data. It is found that the Total Pressure drop in the pore system may be as much as 1% of the ambient Total Pressure. This results in a maximum viscous flow contribution of 13% for the cases studied. Since this contribution is obtained only under conditions of low overall transport rates of the adsorbed component, the assumption of isobaric conditions within the pore system of a porous adsorbent appears justified for most cases of practical calculations.

  • Influence of Pore Structure Parameters on the Intraprticle Pressure Change During Adsorption
    Characterization of Porous Solids II Proceedings of the IUPAC Symposium (COPS 11), 1991
    Co-Authors: Stephan Scholl, A.b. Mersmann
    Abstract:

    Abstract The influence of pore structure parameters on intraparticle Total Pressure Change during gas phase adsorption is investigated. Dusty Gas theory is applyed to quantify pore mass transport for the case of non-isothermal, non-isobaric single component adsorption from an inert carrier medium. Comparing the results for activated carbon Chemviron BPL and a large pore adsorbent it is found that intraparticle Total Pressure reduction is less pronounced for the large pore solid. This is due to a larger intraparticle mole flux of the adsorbed component thus resulting in a faster equilibration of the gas phase mole defect caused by adsorption.

Sigrún Hreinsdóttir - One of the best experts on this subject based on the ideXlab platform.

  • Volcanic plume height correlated with magma-Pressure Change at Grímsvötn Volcano, Iceland
    Nature Geoscience, 2014
    Co-Authors: Sigrún Hreinsdóttir, Freysteinn Sigmundsson, Matthew Roberts, Halldór Björnsson, Ronni Grapenthin, Pórdur Arason, Thóra Árnadóttir, Jósef Hólmjárn, Halldór Geirsson, Richard Bennett
    Abstract:

    Magma flow during volcanic eruptions causes surface deformation that can be used to constrain the location, geometry and internal Pressure evolution of the underlying magmatic source(1). The height of the volcanic plumes during explosive eruptions also varies with magma flow rate, in a nonlinear way(2,3). In May 2011, an explosive eruption at Grimsvotn Volcano, Iceland, erupted about 0.27 km(3) dense-rock equivalent of basaltic magma in an eruption plume that was about 20 km high. Here we use Global Positioning System (GPS) and tilt data, measured before and during the eruption at Grimsvotn Volcano, to show that the rate of Pressure Change in an underlying magma chamber correlates with the height of the volcanic plume over the course of the eruption. We interpret ground deformation of the volcano, measured by geodesy, to result from a Pressure drop within a magma chamber at about 1.7 km depth. We estimate the rate of magma discharge and the associated evolution of the plume height by differentiating the co-eruptive Pressure drop with time. The time from the initiation of the Pressure drop to the onset of the eruption was about 60 min, with about 25% of the Total Pressure Change preceding the eruption. Near-real-time geodetic observations can thus be useful for both timely eruption warnings and for constraining the evolution of volcanic plumes.

  • Volcanic plume height correlated with magma-Pressure Change at Grímsvötn Volcano, Iceland
    Nature Geoscience, 2014
    Co-Authors: Sigrún Hreinsdóttir, Freysteinn Sigmundsson, Halldór Björnsson, Ronni Grapenthin, Pórdur Arason, Thóra Árnadóttir, Jósef Hólmjárn, Halldór Geirsson, Matthew J. Roberts, Richard A. Bennett
    Abstract:

    The 2011 eruption of a 20-km-high volcanic plume from Grímsvötn Volcano, Iceland, led to the closure of northern European airspace. Geodetic measurements from the volcano reveal a correlation between plume height, surface deformation and magma-chamber Pressure, with a delay of an hour, implying that volcanic-plume behaviour can be predicted before eruption onset. Magma flow during volcanic eruptions causes surface deformation that can be used to constrain the location, geometry and internal Pressure evolution of the underlying magmatic source^ 1 . The height of the volcanic plumes during explosive eruptions also varies with magma flow rate, in a nonlinear way^ 2 , 3 . In May 2011, an explosive eruption at Grímsvötn Volcano, Iceland, erupted about 0.27 km^3 dense-rock equivalent of basaltic magma in an eruption plume that was about 20 km high. Here we use Global Positioning System (GPS) and tilt data, measured before and during the eruption at Grímsvötn Volcano, to show that the rate of Pressure Change in an underlying magma chamber correlates with the height of the volcanic plume over the course of the eruption. We interpret ground deformation of the volcano, measured by geodesy, to result from a Pressure drop within a magma chamber at about 1.7 km depth. We estimate the rate of magma discharge and the associated evolution of the plume height by differentiating the co-eruptive Pressure drop with time. The time from the initiation of the Pressure drop to the onset of the eruption was about 60 min, with about 25% of the Total Pressure Change preceding the eruption. Near-real-time geodetic observations can thus be useful for both timely eruption warnings and for constraining the evolution of volcanic plumes.

Richard A. Bennett - One of the best experts on this subject based on the ideXlab platform.

  • Volcanic plume height correlated with magma-Pressure Change at Grímsvötn Volcano, Iceland
    Nature Geoscience, 2014
    Co-Authors: Sigrún Hreinsdóttir, Freysteinn Sigmundsson, Halldór Björnsson, Ronni Grapenthin, Pórdur Arason, Thóra Árnadóttir, Jósef Hólmjárn, Halldór Geirsson, Matthew J. Roberts, Richard A. Bennett
    Abstract:

    The 2011 eruption of a 20-km-high volcanic plume from Grímsvötn Volcano, Iceland, led to the closure of northern European airspace. Geodetic measurements from the volcano reveal a correlation between plume height, surface deformation and magma-chamber Pressure, with a delay of an hour, implying that volcanic-plume behaviour can be predicted before eruption onset. Magma flow during volcanic eruptions causes surface deformation that can be used to constrain the location, geometry and internal Pressure evolution of the underlying magmatic source^ 1 . The height of the volcanic plumes during explosive eruptions also varies with magma flow rate, in a nonlinear way^ 2 , 3 . In May 2011, an explosive eruption at Grímsvötn Volcano, Iceland, erupted about 0.27 km^3 dense-rock equivalent of basaltic magma in an eruption plume that was about 20 km high. Here we use Global Positioning System (GPS) and tilt data, measured before and during the eruption at Grímsvötn Volcano, to show that the rate of Pressure Change in an underlying magma chamber correlates with the height of the volcanic plume over the course of the eruption. We interpret ground deformation of the volcano, measured by geodesy, to result from a Pressure drop within a magma chamber at about 1.7 km depth. We estimate the rate of magma discharge and the associated evolution of the plume height by differentiating the co-eruptive Pressure drop with time. The time from the initiation of the Pressure drop to the onset of the eruption was about 60 min, with about 25% of the Total Pressure Change preceding the eruption. Near-real-time geodetic observations can thus be useful for both timely eruption warnings and for constraining the evolution of volcanic plumes.

Jósef Hólmjárn - One of the best experts on this subject based on the ideXlab platform.

  • Volcanic plume height correlated with magma-Pressure Change at Grímsvötn Volcano, Iceland
    Nature Geoscience, 2014
    Co-Authors: Sigrún Hreinsdóttir, Freysteinn Sigmundsson, Matthew Roberts, Halldór Björnsson, Ronni Grapenthin, Pórdur Arason, Thóra Árnadóttir, Jósef Hólmjárn, Halldór Geirsson, Richard Bennett
    Abstract:

    Magma flow during volcanic eruptions causes surface deformation that can be used to constrain the location, geometry and internal Pressure evolution of the underlying magmatic source(1). The height of the volcanic plumes during explosive eruptions also varies with magma flow rate, in a nonlinear way(2,3). In May 2011, an explosive eruption at Grimsvotn Volcano, Iceland, erupted about 0.27 km(3) dense-rock equivalent of basaltic magma in an eruption plume that was about 20 km high. Here we use Global Positioning System (GPS) and tilt data, measured before and during the eruption at Grimsvotn Volcano, to show that the rate of Pressure Change in an underlying magma chamber correlates with the height of the volcanic plume over the course of the eruption. We interpret ground deformation of the volcano, measured by geodesy, to result from a Pressure drop within a magma chamber at about 1.7 km depth. We estimate the rate of magma discharge and the associated evolution of the plume height by differentiating the co-eruptive Pressure drop with time. The time from the initiation of the Pressure drop to the onset of the eruption was about 60 min, with about 25% of the Total Pressure Change preceding the eruption. Near-real-time geodetic observations can thus be useful for both timely eruption warnings and for constraining the evolution of volcanic plumes.

  • Volcanic plume height correlated with magma-Pressure Change at Grímsvötn Volcano, Iceland
    Nature Geoscience, 2014
    Co-Authors: Sigrún Hreinsdóttir, Freysteinn Sigmundsson, Halldór Björnsson, Ronni Grapenthin, Pórdur Arason, Thóra Árnadóttir, Jósef Hólmjárn, Halldór Geirsson, Matthew J. Roberts, Richard A. Bennett
    Abstract:

    The 2011 eruption of a 20-km-high volcanic plume from Grímsvötn Volcano, Iceland, led to the closure of northern European airspace. Geodetic measurements from the volcano reveal a correlation between plume height, surface deformation and magma-chamber Pressure, with a delay of an hour, implying that volcanic-plume behaviour can be predicted before eruption onset. Magma flow during volcanic eruptions causes surface deformation that can be used to constrain the location, geometry and internal Pressure evolution of the underlying magmatic source^ 1 . The height of the volcanic plumes during explosive eruptions also varies with magma flow rate, in a nonlinear way^ 2 , 3 . In May 2011, an explosive eruption at Grímsvötn Volcano, Iceland, erupted about 0.27 km^3 dense-rock equivalent of basaltic magma in an eruption plume that was about 20 km high. Here we use Global Positioning System (GPS) and tilt data, measured before and during the eruption at Grímsvötn Volcano, to show that the rate of Pressure Change in an underlying magma chamber correlates with the height of the volcanic plume over the course of the eruption. We interpret ground deformation of the volcano, measured by geodesy, to result from a Pressure drop within a magma chamber at about 1.7 km depth. We estimate the rate of magma discharge and the associated evolution of the plume height by differentiating the co-eruptive Pressure drop with time. The time from the initiation of the Pressure drop to the onset of the eruption was about 60 min, with about 25% of the Total Pressure Change preceding the eruption. Near-real-time geodetic observations can thus be useful for both timely eruption warnings and for constraining the evolution of volcanic plumes.

Halldór Geirsson - One of the best experts on this subject based on the ideXlab platform.

  • Volcanic plume height correlated with magma-Pressure Change at Grímsvötn Volcano, Iceland
    Nature Geoscience, 2014
    Co-Authors: Sigrún Hreinsdóttir, Freysteinn Sigmundsson, Matthew Roberts, Halldór Björnsson, Ronni Grapenthin, Pórdur Arason, Thóra Árnadóttir, Jósef Hólmjárn, Halldór Geirsson, Richard Bennett
    Abstract:

    Magma flow during volcanic eruptions causes surface deformation that can be used to constrain the location, geometry and internal Pressure evolution of the underlying magmatic source(1). The height of the volcanic plumes during explosive eruptions also varies with magma flow rate, in a nonlinear way(2,3). In May 2011, an explosive eruption at Grimsvotn Volcano, Iceland, erupted about 0.27 km(3) dense-rock equivalent of basaltic magma in an eruption plume that was about 20 km high. Here we use Global Positioning System (GPS) and tilt data, measured before and during the eruption at Grimsvotn Volcano, to show that the rate of Pressure Change in an underlying magma chamber correlates with the height of the volcanic plume over the course of the eruption. We interpret ground deformation of the volcano, measured by geodesy, to result from a Pressure drop within a magma chamber at about 1.7 km depth. We estimate the rate of magma discharge and the associated evolution of the plume height by differentiating the co-eruptive Pressure drop with time. The time from the initiation of the Pressure drop to the onset of the eruption was about 60 min, with about 25% of the Total Pressure Change preceding the eruption. Near-real-time geodetic observations can thus be useful for both timely eruption warnings and for constraining the evolution of volcanic plumes.

  • Volcanic plume height correlated with magma-Pressure Change at Grímsvötn Volcano, Iceland
    Nature Geoscience, 2014
    Co-Authors: Sigrún Hreinsdóttir, Freysteinn Sigmundsson, Halldór Björnsson, Ronni Grapenthin, Pórdur Arason, Thóra Árnadóttir, Jósef Hólmjárn, Halldór Geirsson, Matthew J. Roberts, Richard A. Bennett
    Abstract:

    The 2011 eruption of a 20-km-high volcanic plume from Grímsvötn Volcano, Iceland, led to the closure of northern European airspace. Geodetic measurements from the volcano reveal a correlation between plume height, surface deformation and magma-chamber Pressure, with a delay of an hour, implying that volcanic-plume behaviour can be predicted before eruption onset. Magma flow during volcanic eruptions causes surface deformation that can be used to constrain the location, geometry and internal Pressure evolution of the underlying magmatic source^ 1 . The height of the volcanic plumes during explosive eruptions also varies with magma flow rate, in a nonlinear way^ 2 , 3 . In May 2011, an explosive eruption at Grímsvötn Volcano, Iceland, erupted about 0.27 km^3 dense-rock equivalent of basaltic magma in an eruption plume that was about 20 km high. Here we use Global Positioning System (GPS) and tilt data, measured before and during the eruption at Grímsvötn Volcano, to show that the rate of Pressure Change in an underlying magma chamber correlates with the height of the volcanic plume over the course of the eruption. We interpret ground deformation of the volcano, measured by geodesy, to result from a Pressure drop within a magma chamber at about 1.7 km depth. We estimate the rate of magma discharge and the associated evolution of the plume height by differentiating the co-eruptive Pressure drop with time. The time from the initiation of the Pressure drop to the onset of the eruption was about 60 min, with about 25% of the Total Pressure Change preceding the eruption. Near-real-time geodetic observations can thus be useful for both timely eruption warnings and for constraining the evolution of volcanic plumes.