• Title/Summary/Keyword: 확산오염

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Adsorption-Desorption Modeling of Pollutants on Granular Activated Carbon (오염물질에 대한 입상 활성탄의 흡·탈착 모델링)

  • Wang, Chang Keun;Weber, Walter J. Jr.
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.2
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    • pp.279-285
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    • 1993
  • It is important to understand the interrelationship between adsorption, equilibrium and mass transport in efficient design and operation of the granular activated carbon(GAC) adsorption systems. In this study, the micro-diameter-depth adsorption system(MIDDAS) technique was developed to estimate equilibrium and mass transport parameters, which were utilized to simulate adsorption and mass transport phenomena dynamically and mathematically. The homogeneous surface diffusion model(HSDM) utilizing the estimated equilibrium and mass transport parameters including the film transfer coefficients and surface diffusivities from the MIDDAS technique, successfully predicted competitive adsorption, desorption and chromatographic displacement effects. In the binary solute system of p-chlorophenol(PCP) and p-nitrophenol(PNP), PCP was displaced by PNP and the HSDM could predict successfully. While the HSDM described the desorption breakthrough curves for PCP, PNP and PTS well when complete reversible adsorption was assumed, the desorption breakthrough curves for DBS could be predicted after subsequent incorporation of the degree of irreversibility into the model simulations.

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Permeability Characteristics of Geosynthetics Vertical Barrier Connections for the Prevention of Contaminants Diffusion (오염물질 확산방지를 위한 토목섬유 연직차수벽 연결부의 투수성능 평가)

  • Park, Jeong Jun
    • Journal of the Society of Disaster Information
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    • v.18 no.1
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    • pp.1-9
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    • 2022
  • Purpose: In this study, we used hydrophilic waterstop used in geosynthetics vertical barrier system to evaluate the performance of impermeability under sealing conditions. Method: ASTM D5887 and ASTM D6766 were applied to determine the capability of the connection during the geosynthetics vertical barrier system. Hydrophilic waterstop was saturated in each solution and the weight, thickness, and volume changes were analyzed over elapsed time. Hydrophilic waterstop was installed at the geosynthetics vertical barrier system connection to evaluate the permeability characteristics. Results: As the expansion reaction time of hydrophilic waterstop increased relatively under saline conditions, the decrease in permeability also showed a smaller decrease in fresh water. Furthermore, the method of engagement of the geosynthetics vertical barrier system showed somewhat better performance of the impermeability due to the large pressure resistance caused by the roll joint type than interlock type. Conclusion: In urban pollutants, which can estimate the outflow of pollutants such as oil storage facilities and industrial complexes, proactive response technologies that can prevent the contaminant diffusion can significantly reduce the damage.