• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2001년도 봄 학술발표회 논문집
• /
• pp.405-410
• /
• 2001

Bioremediation is a degradation process of existing organic contaminants in soils and groundwater by indigenous or inoculated microorganisms. This process can provide economical solution as well as safe and effective alternative in remediation technologies. However, it has been suggested that the rate of bioremediation process of organic contaminants by microorganisms can be limited by the concentration of nutrients and TEAs(Terminal Electron Accepters). In in-situ bioremediation, conventional pumping techniques have been used for supplying these additives. However, the injection of these additives is difficult in low permeable soils, and also hindered by preferential flow paths resulting from heterogeneities in high permeable ground. Therefore, the Injection of chemical additives is the most significant concern in in-situ bioremediation. Most recently, electrokinetic technique has been applied into the bioremediation and the injection characteristics under electrokinetics have not been examined in various soil types. Therefore, in this study, electrokinetic injection method is investigated in kaolinite and sand, and the concentration of ammonium(nutrients) and sulfate(TEAs) in soil is presented.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제7권1호
• /
• pp.15-24
• /
• 2002

현재 원위치 bioremediation을 목적으로 EK (electrokinetlc)기법에 의한 영양분과 TEAs (Terminal electron accepters) 공급이 연구되고 있으나, 아직까지 다양한 토질에서의 EK 주입특성 연구는 미비하다. 따라서 본 연구에서는 카올린과 모래시료에 대하여 영양분인 암모늄이온과 TEAs로서 황산염이온의 EK주입실험을 수행하였다. EK주입에 의한 암모늄이온의 경우 카올린에서는 주입부(양극)에서 높은 농도분포를 보이며, 특별히 모래의 경우는 음극에서 더욱 높은 농도분포를 보인다. 황산염이온의 주입분포는 두 시료에서 모두 균일한 주입분포를 보이지만 두 시료에서의 농도차는 크게 달랐다. 따라서 원위치 bioremediation에 EK 주입기법을 이용할 경우 토질에 따른 주입특성의 평가가 가장 중요하게 고려되어야 한다.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2002년도 추계학술발표회
• /
• pp.351-354
• /
• 2002

In this study, variation of electrochemical parameters and characteristics of lead immobilization due to phosphoric acid injection in soil were studied during electrokinetic remediation of lead contaminated soil. TCLP result showed about 100% of soil was satisfied TCLP regulation criteria. And injected ion from cathode reservoir by ionmigration was proportionate to concentration of phosphoric acid and elapsed time. Therefore, when removal is infeasible or not cost-effective, in situ immobilization method would be more effective.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2003년도 추계학술발표회
• /
• pp.310-313
• /
• 2003

The precipitation of heavy metals within the region of pH jump is inevitable in the conventional electrokinetic remediation technology. This study prevents the interest species from precipitating through the injection of flushing solutions in which HCl, acetic acid, citric acid, EDTA and SDS dissolved. The cumulative flow resulted from electroosmosis appear in order of Citric acid

• 분석과학
• /
• 제9권1호
• /
• pp.35-42
• /
• 1996

원자력 발전소의 배관 부식 등의 방지를 위하여 초순수에 첨가되는 고순도 시약 중의 미량 음이온 성분올 모세관 전기영동법에 의하여 정량하는 분석법을 개발하였다. 전해질은 5mM 크롬산염(pH=8.0)을, 캐필러리는 내경이 50 또는 $75{\mu}m$인 석영 캐필러리 내부를 염화 삼메틸 실란으로 처리하여 사용하였다. 기타 기기 조건은 전압 20kV, 검출은 254nm에서 간접 자외흡수법을 사용하였고 주요 정량 성분은 $Cl^-$, $NO{_3}^-$, $SO{_4}^{2-}$, $N{_3}^-$, $PO{_4}^{3-}$등이며, 시료 주입은 시료 농도가 1ppm 이상일 때는 유체역학적 주입법으로, 1ppm 이하는 계면 동전기 주입법을 적용하였다. 특히 본 연구에서는 시료 주입시 공존 이온의 영향을 조사한 결과 유체역학적으로 시료를 주입할 때는 시료 내 공존하는 음이온의 영향이 크게 없었으나, 계면 동전기적인 시료 주입시에는 공존하는 이온량과 전기영동적 이동도에 따라 분석 이온의 신호 크기가 크게 변함을 확인하였으며, 각 분석 성분 주입량, 즉 신호 크기는 시료 용액의 저항에 비례하였다. 따라서, 분석 이온보다 과량의 공존 이온 존재하에 계면 동전기 주입법으로 분석할 경우 시료 용액과 표준 용액의 전기 전도도 차이를 보상할 수 있는 표준물 첨가법 또는 내부 표준물법 등의 적절한 방법을 반드시 사용해야 한다.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2000년도 창립총회 및 춘계학술발표회
• /
• pp.20-23
• /
• 2000

The use of electrokinetic injection and transport for the distribution of an NAPLs-degrading microorganism in a sandy soil bed was studied. After the injection of the cell into cathode side of bed, an electric current was applied. The transport of cell though the sandy soil was achieved by electokinetics, mainly by electrophoresis, The pH control in electrode chamber plays un important role to achieve desirable cell transport because H$^{+}$ generated at anode is toxic or inhibits the transport of cells. Electokinetic distribution rate of bacterial cells changed depending on the applied electric current and pH. The degradation of diesel by electrokinetically transport cells were monitored.d.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
• /
• pp.31-34
• /
• 2004

Feasibility of electrokinetic(EK)-Fenton process and Ozone chemical oxidation were investigated for tile removal of organic contaminants and heavy metals from the contaminated soil. In EK-Fenton process, accumulated electroosmotic flow(EOF) was 80 L for 26 days. Removal efficiency of TPH, As, and Ni were 61%, 36%, and 47%, respectively. The concentration of As was high near the anode due to the transport of anionic As toward the anode, while the concentration of Ni was high near the cathode by the movement of cationic Ni to the cathode. Field scale application of in-situ ozonation was carried out for removal of TPH in 3-D test cell (3 m$\times$2 m$\times$2 m). After 25 days of ozone injection, more than 80% of removal rate was observed through the test cell.

• Journal of Microbiology and Biotechnology
• /
• 제11권6호
• /
• pp.1038-1045
• /
• 2001

The electrokinetic technology was applied in bioremediation for the purpose of supplying a Pseudomonas strain capable of degrading diesel to contaminated soil bed, and their biodegradation of diesel was carried out after a desired cell distribution was obtained. Electrokinetic injection of the strain was made possible because the cells acted as negatively charged particles at neutral pH, and thus the cells were transported with a precise directionality through the soil mostly by the mechanism of electrophoresis and in part by electroosmosis. A severe pH change in the soil bed was formed due to the penetration of electrolysis products, which was harmful to the cell viability and cell transport. To achieve a desirable cell transport and distribution, the control of pH in soil bed by a recirculating buffer solution in electrode chambers was essential during the appliation of an electric field. The judicious selections of electrolyte concentration and conductivity were also important for achieving an efficient electrokinetic cell transport since a higher electrolyte concentration favored the maintenance of pH stability in soil bed, but lowered electrophoretic mobility on the other hand. With electrolyte solution of pH 7 phosphate buffer, a 0.05 M concentration showed a better cell transport buffer, a 0.05 M concentration showed a better cell transport than 0.02 M and 0.08 M. The cell under pH 8 were obtained, compared to the cells under pH 7 or pH 9 in a given time period Up to $60\%$ of diesel was degraded in 8 days by the Pseudomonas cell, which were distributed electrokinetically under the conditions of pH 8 ($1,800{\mu}S/cm$, a mixture of phosphate and ammonia buffers) and 40 mA in a soil bed of 15 cm length.

• 방사성폐기물학회지
• /
• 제7권3호
• /
• pp.153-160
• /
• 2009

방사성 토양을 복원하기 위해 원자력시설 주변 부지의 수리지질 특성을 분석하여 국내 방사성 토양 복원에 적합한 수직형 동전기세정장치를 개발하였다. 또한, 이 수직형 동전기세정장치를 이용한 실험을 통해 원자력시설 주변 방사성토양을 복원하기 위한 최적 세정제를 선정하고 단기간에 높은 제거효율을 확보할 수 있는 최적제염조건들을 도출하였다. 초산을 세정제로 사용하였을 때 토양으로부터 코발트와 세슘의 제거효율이 가장 높으므로 동전기제염을 위한 최적 세정제로 초산을 선정하였다 동전기세정제염 시 세정제 주입량을 증가 시켰을 때 토양으로부터 코발트와 세슘의 제거효율은 평균 약 4.6% 제거효율이 증가했고 토양폐액 발생량도 동전기제염의 1.5배 인 2.4mL/g이었다. 동전기토양셀의 전압구배를 2배로 증가시켜 4 V/cm를 적용시켰을 때, 코발트와 세슘의 제거효율은 각각 98.9%와 96.7%로 평균 약 4.3% 제거효율이 증가했다. 그리고 세정제 농도를 0.01M로부터 0.05M로 증가시킨 후 제염실험 결과 코발트의 제거효율은 상승했지만 세슘의 제거효율은 감소하였다. 위 실험결과 개발한 수직형 동전기세정장치의 최적제염조건으로 제염시간은 20일 동안 초산 $0.01M{\sim}0.05M$을 세정제로 사용하여 동전기토양셀의 전압구배는 4 V/cm를 가하고, 2.4mL/g의 세정제를 주입하는 것이다.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2005년도 춘계 학술발표회 논문집
• /
• pp.910-915
• /
• 2005

In this study a series of tests(bench scale test) are carried out for increasing in 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. The test results show that the strength increase was developed approximately double to 7 times in comparison to initial shear strength, and outstanding strength 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 were high as 1000% on average