Pore-Water Extraction Intermediate-Scale Laboratory Experiments and Numerical Simulations

Oostrom, Martinus; Freedman, Vicky L; Wietsma, Thomas W; Truex, Michael J

doi:10.2172/1029434

Title: Pore-Water Extraction Intermediate-Scale Laboratory Experiments and Numerical Simulations

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Abstract

A series of flow cell experiments was conducted to demonstrate the process of water removal through pore-water extraction in unsaturated systems. In this process, a vacuum (negative pressure) is applied at the extraction well establishing gas and water pressure gradients towards the well. The gradient may force water and dissolved contaminants, such as 99Tc, to move towards the well. The tested flow cell configurations consist of packings, with or without fine-grained well pack material, representing, in terms of particle size distribution, subsurface sediments at the SX tank farm. A pore water extraction process should not be considered to be equal to soil vapor extraction because during soil vapor extraction, the main goal may be to maximize gas removal. For pore water extraction systems, pressure gradients in both the gas and water phases need to be considered while for soil vapor extraction purposes, gas phase flow is the only concern. In general, based on the limited set (six) of flow experiments that were conducted, it can be concluded that pore water extraction rates and cumulative outflow are related to water content, the applied vacuum, and the dimensions of the sediment layer providing the extracted water. In particular, it was observed thatmore »« less

Authors:: Oostrom, Martinus; Freedman, Vicky L; Wietsma, Thomas W; Truex, Michael J

Publication Date:: Thu Jun 30 00:00:00 EDT 2011

Research Org.:: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1029434

Report Number(s):: PNNL-20507
42793; 24992; 830403000; TRN: US201201%%129

DOE Contract Number:: AC05-76RL01830

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 54 ENVIRONMENTAL SCIENCES; DIMENSIONS; DISTRIBUTION; PARTICLE SIZE; PRESSURE GRADIENTS; REMOVAL; SEDIMENTS; SOILS; STORAGE FACILITIES; WATER; WATER REMOVAL; pore water extraction; intermediate-scale experiments; Environmental Molecular Sciences Laboratory

Citation Formats


                    Oostrom, Martinus, Freedman, Vicky L, Wietsma, Thomas W, and Truex, Michael J. Pore-Water Extraction Intermediate-Scale Laboratory Experiments and Numerical Simulations.  United States: N. p., 2011. 
        Web.  doi:10.2172/1029434.

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                    Oostrom, Martinus, Freedman, Vicky L, Wietsma, Thomas W, & Truex, Michael J. Pore-Water Extraction Intermediate-Scale Laboratory Experiments and Numerical Simulations.  United States.  https://doi.org/10.2172/1029434

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                    Oostrom, Martinus, Freedman, Vicky L, Wietsma, Thomas W, and Truex, Michael J. 2011.  
        "Pore-Water Extraction Intermediate-Scale Laboratory Experiments and Numerical Simulations".  United States.  https://doi.org/10.2172/1029434.  https://www.osti.gov/servlets/purl/1029434.

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@article{osti_1029434,

  title        = {Pore-Water Extraction Intermediate-Scale Laboratory Experiments and Numerical Simulations},

  author       = {Oostrom, Martinus and Freedman, Vicky L and Wietsma, Thomas W and Truex, Michael J},

  abstractNote = {A series of flow cell experiments was conducted to demonstrate the process of water removal through pore-water extraction in unsaturated systems. In this process, a vacuum (negative pressure) is applied at the extraction well establishing gas and water pressure gradients towards the well. The gradient may force water and dissolved contaminants, such as 99Tc, to move towards the well. The tested flow cell configurations consist of packings, with or without fine-grained well pack material, representing, in terms of particle size distribution, subsurface sediments at the SX tank farm. A pore water extraction process should not be considered to be equal to soil vapor extraction because during soil vapor extraction, the main goal may be to maximize gas removal. For pore water extraction systems, pressure gradients in both the gas and water phases need to be considered while for soil vapor extraction purposes, gas phase flow is the only concern. In general, based on the limited set (six) of flow experiments that were conducted, it can be concluded that pore water extraction rates and cumulative outflow are related to water content, the applied vacuum, and the dimensions of the sediment layer providing the extracted water. In particular, it was observed that application of a 100-cm vacuum (negative pressure) in a controlled manner leads to pore-water extraction until the water pressure gradients towards the well approach zero. Increased cumulative outflow was obtained with an increase in initial water content from 0.11 to 0.18, an increase in the applied vacuum to 200 cm, and when the water-supplying sediment was not limited. The experimental matrix was not sufficiently large to come to conclusions regarding maximizing cumulative outflow.},

  doi          = {10.2172/1029434},

  url          = {https://www.osti.gov/biblio/1029434},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Thu Jun 30 00:00:00 EDT 2011},

  month        = {Thu Jun 30 00:00:00 EDT 2011}

}

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