• Title/Summary/Keyword: Electrokinetic (EK)

Search Result 44, Processing Time 0.019 seconds

Remediation of Electroplating Contaminated Soil by a Field Scale Electrokinetic System with Stainless Steel Electrodes

  • Yuan, Ching;Tsai, Chia-Ren;Hung, Chung-Hsuang
    • Journal of Soil and Groundwater Environment
    • /
    • v.19 no.5
    • /
    • pp.26-34
    • /
    • 2014
  • A $1.5m(L){\times}1.0m(W){\times}1.1m(H)$ polypropylene (PP) field scale electroniketic system coupled with stainless steel electrodes was designed to examined metal removal performance applied 0.2-0.35 V/cm potential gradient and 0.05-0.5M lactic acid for 20 day. Electroosmosis permeabilities of $2.2{\times}10^{-5}cm^2/V-s$ to $4.8{\times}10^{-5}cm^2/V-s$ were observed and it increased with the potential gradient increased. The reservoir pH controlled at $7.0{\pm}1.0$ has been effectively diminished the clogging of most metal oxides. The best removal efficiency of Zn, Pb, and Ni was 78.4%, 84.3%, and 40.1%, respectively, in the field scale EK system applied 0.35 V/cm and 0.05M lactic acid for 20 days. Increasing potential gradient would more effectively enhance metal removal than increasing concentration of processing fluid. The reservoir and soil temperatures were majorly related to potential gradient and power consumptio. A $4-16^{\circ}C$ above room temperature was observed in the investigated system. It was found that the temperature increase in soil transported the pore water and metals from bottom to the topsoil. This vertical transport phenomenon is critical for the electrokinetic process to remediate in-situ deep pollution.

Effect on electrolyte concentration during the ElectroKinetic-Fenton Process for contaminated soil around railroad turnout (선로분기기 주변 철도토양의 동전기-펜톤 공정 정화에 따른 전해질 농도의 영향)

  • Kang, Hae-Suk;Jung, Woo-Sung;Yun, Sung-Taek;Kwon, Tae-Soon;Lee, Cheul-Kyu;Kim, Hee-Man
    • Proceedings of the KSR Conference
    • /
    • 2010.06a
    • /
    • pp.1997-2001
    • /
    • 2010
  • Generally, railroad soil around turnout was caused by leakage of lubricant oils during its maintenance. So, TPH concentration in soil was much higher than standard in Soil Envirnment Law. In additiont, railroad site was still difficult to assess due to railcar operation. This research was conducted to investigate the effect on electrolyte concentration during the Electrokinetic-Fenton process for contaminated soil around railroad turnout. As a result, experimental result shows that TPH removal in soil and amount of EOF were changed depending on electrolyte concentration. In future, the removal efficiency can be enhanced to optimize concentration in EK-Fenton Process.

  • PDF

Application of Electrokinetic Injection Method for Increasing Shear Strength of Low Permeable Soil (저투수성 지반의 전단강도 증가를 위한 동전기 주입 기법의 적용성)

  • Kim Soo-Sam;Han Sang-Jae;Kim Ki-Nyeon
    • Journal of the Korean Geotechnical Society
    • /
    • v.22 no.5
    • /
    • pp.5-12
    • /
    • 2006
  • In this study a series of tests (bench scale test) are carried out for increasing the strength of clayey soil by EK-Injection method. In addition, the effects of strength increase in the treated sample are measured by operating the vane shear test device during 25 days at 5 days intervals in order to estimate the effect of ground improvement caused by diffusion. Also, the effects of strength increase in the treated sample are measured by operating the vane shear test device to estimate the effect by treatment durations (5, 10, 15, 20, 25). The test results show that the strength increase was developed approximately 2 to 7 times in comparison to initial shear strength, and outstanding strenfth increase was created as much as 7 times while injecting the sodium silicate and phosphoric acid in anolyte and catholyte. In addition, the measured shear strength with the influence of diffusion and reduction of water-content had a tendency to converge in constant value in proportion to elapsed time. As a result of this study, strength increment developed by the influence of EK-Injection and diffusion rather than the reduction of water-content was 1000% high on average. In case of changes of treatment duration, strength increment developed by the influence of treatment durations rather than the reduction of water-content was 3 to 4 times high on average.

Bacterial Behavior in Soil under Electric Field and its Effect on Electrokientic Bioremediation (전기장하 토양내에서 미생물 이동특성과 동전기 생물학적복원의 효과)

  • Kim, Sang-Joon;Park, Ji-Yeon;Lee, You-Jin;Yang, Ji-Won
    • KSBB Journal
    • /
    • v.21 no.3
    • /
    • pp.175-180
    • /
    • 2006
  • In this study, it could be found that the microbial movement in soil under electric field mainly occurred by electrophoresis and electroosmosis. The contribution of electrophoresis on the microbial mobility and flux was generally higher than that of electroosmosis. In the electrokinetic(EK) bioremediation of a pentadecane-contaminated soil, the microbial population increased simultaneously at anode and cathode regions of the soil specimen because both electrophoresis and electroosmosis affected on the microbial movement. After initial operation, the microbial population was high in order of anode, middle, and cathode regions due to their negatively-charged surface and oxygen generation at anode. However, the uniform contaminant removal was achieved by the microbial movement with two-directionality.