• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.302-306
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• 2000

In case of applying electrokinetic remediation, magnitude of electric current is one of major factors for estimation of contaminant transport. In practice, electric current provide determination of electric conductivity based on specimen resistance. Electric current variation is produced during Electrokinetic remediation test. Electric current is decreased by expotential function according to time in condition of constant voltage. This can be interpreted as precipitation effect by OH$^{-10}$ generation in a cathode.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.873-881
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• 2004

A serious of EK remediation tests on contaminated soil are performed under unsaturated conditions and analyzed for electrical potential, water content, pH and so on. The results indicated that electrical potential and pH distributions in the sample are dependent on the amount and inward/outward flow of hydrogen ion. Specially, for the closed system the water content is largely decreased with the flow of hydrogen. The maximum electrical conductivity is measured at the catholyte of CEM(Sealing) test and directly related to the remedial efficiency. Although pHs in the region near to the anode are similarly developed, the different concentration of lead is measured with the electrical gradient contrary to the lead concentration dependent on pH within the sample.

• 한국지하수토양환경학회지:지하수토양환경
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• 제9권1호
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• pp.54-62
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• 2004

본 연구에서는 납으로 오염된 유기물과 철성분이 다량 함유된 철성분 함유토에 대한 정화 효율을 향상시키기 위해 세척제로 산, 킬레이트제 및 계면활성제를 사용하여 동전기 정화실험을 실시하였다. 실험결과 주입되는 세척제의 pH가 낮을수록 양극(兩極)저수조의 pH는 더 빠른 시간에 정상상태 값에 도달하였으며, 전압 분포의 경우 세척제 종류에 따른 차이는 크게 나타나지 않았고, 주입용액의 농도가 증가함에 따라 (+)극으로부터 정규화된 거리인 0.9지점에서의 전압은 더 크게 나타나는 경향을 보였다. 또한, 음이온성 계면활성제인 SDS가 가장 높은 잔류 납농도 분포를 보였다. 세척제 농도의 경우 1 mM의 Acetic acid에서 가장 양호한 정화효율을 보였지만, 아세트산의 농도 변화는 철성분 함유토(Ferrous soil)의 동전기 정화 효율에 큰 영향을 미치지 않는 것으로 나타났다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.890-896
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• 2004

This study is intended as an investigation of the EK remediation characteristics of natural soil with treatment time under unsaturated conditions. EK tests are performed under the voltage gradient of 1V/cm, the degree of saturation of 82.8%, and the installing of cation exchange membrane. It was found from the results that the acid front is initially transported at 0.75cm/day and then continuously degreased until the transport velocity of the acid front is balanced to the velocity of the base front. The residual lead concentration indicated the maximum value at the treatment time of lOdays, then the increasing of treatment time largely decreases the concentration within the sample though electromigration than electroosmosis.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.484-490
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• 2003

Fundamental data was obtained to apply to the real contaminated soil of railroad by analyzing pollutant-elimination efficiency and process variables through electro-kinetic technology as well as by investigating Pollution sources of railroad soil contaminated by oil and pollution propensities.

• 한국지반공학회논문집
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• 제18권1호
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• pp.49-57
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• 2002

오염지반 정화를 위한 Electrokinetic 처리 과정에서 지반에 전류를 적용하면 흙물 시스템 내에서 발생하는 유체의 이동 현상과 계면의 특성 변화가 발생하여 Electrokinetic 반응에 영향을 미친다. 본 논문에서는 지반 내에서 발생하는 전기적, 화학적 변수와 그 변화 특성을 규명하고자 실내실험을 수행하여, 시료의 전압, 전류, 제타포텐셜, pH등의 전기 화학적 현상을 연구하였으며 이러한 인자들의 특성변화를 모델링하는 기법을 제시하였다. 그 결과 정화 도중 전압, 전류 변화를 각 농도에서 시간에 따른 지수함수로 표현할 수 있었으며 제타포텐셜의 변화를 pH와 오염농도에 따라 모델링 할 수 있었다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.25-39
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• 2003

Risk and exposure assessment for subsurface environment is very important for both aspects of health and environmental protection as well as making decision of remedial goal for engineering activities. Exposure due to hazardous chemicals in the subsurface environment is essential to assess risk lev121 to individual person, especially from soil and groundwater environmental media. In this paper, the status of soil and groundwater contamination is presented to discuss on the problem for environmental risk assessment. The methodologies of fate and exposure models are also discussed by conducting the case studies of exposure assessment for heavy metals, organic compounds, and dioxin compounds. In addition, the structure of exposure models and available data for model calculation are examined to make clear more realistic exposure scenarios and the application to the practical environmental issues. Three kinds of advanced remediation techniques for soil and groundwater contamination are described in this paper, The most practical method for VOCs is the bio-remediation technique in which biological process due to consortium of microorganisms can be applied. For more effective remediation of soil contaminated by heavy metals we have adopted the soil flushing technique and clean-up system using electro-kinetic method. We have also developed the advanced techniques of geo-melting method for soil contaminated by DXNs and PCB compounds. These techniques are planed to introduce and to apply for a lot of contaminated sites in Japan.

• Environmental Engineering Research
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• 제22권2호
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• pp.141-148
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• 2017

Globalization, industrialization, mining, and uncontrolled population growth have fostered a shortage of potable water. Therefore, it has become imperative to understand an effective and reasonable water purification technique. A renewed interest in electrocoagulation (EC) has been spurred by the search for reliable, cost-effective, water-treatment processes. This paper has elucidated a technical approach for getting rid of heavy metals and total suspended solids (TSS) from synthetic water using an aluminum electrode. The effect of operational parameters, such as current density, inter-electrode distance, operating time, and pH, were studied and evaluated for maximum efficiency. This study corroborates the correlation between current density and removal efficiency. Neutral pH and a low electrode gap have been found to aid the efficacy of the EC setup. The outcome indicates that a maximum TSS removal efficiency of 76.6% occurred at a current density of $5.3mA/cm^2$ during a contact time of 30 min. In the case of heavy metals remediation, 40 min of process time exhibited extremely reduced rates of 99%, 59.2%, and 82.1%, for Cu, Cr, and Zn, respectively. Moreover, kinetic study has also demonstrated that pollutants removal follows first-and second-order model with current density and EC time being dependent.