• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.306-309
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• 2003

Surfactant-enhanced electrokinetic (EK) remediation is an emerging technology that can effectively remove hydrocarbons from low-permeability soils. In this study, the electrokinetic remediation using Calfax 16L-35 was conducted for the removal of phenanthrene from kaolinite. An anionic surfactant Calfax 16L-35 was used at concentrations of 5, 15, and 30g/L to enhance the solubility of phenanthrene. When the surfactant solution was applied to EK system, low electrical potential gradient was maintained because of its ions. Even when the surfactant concentration was high, the removal efficiency of phenanthrene was low After the operation, most of surfactants were remained in soil and there were few in effluent. This phenomena was observed because the migration of Calfax 16L-35 from cathode to anode was predominant over electroosmotic flow which moved in opposite direction. Therefore, the anionic surfactant Calfax 16L-35 is considered to be improper in surfactant - enhanced electrokinetic remediation.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.356-359
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• 2003

Polycyclic aromatic hydrocarbons (PAHs) are representative hydrophobic organic carbons (HOCs). Surfactant-enhanced electrokinetic (EK) remediation is an innovative in-situ technology that can effectively remove HOCs from low-permeability soils. In this study, the electrokinetic remediation using Tergitol 15-S-12, a nonionic surfactant, was conducted for the removal of phenanthrene from kaolinite. Tergitol 15-S-12 was used at concentrations of 1.5, 2.0, 2.5 and 7.5 g/L to enhance the solubility of phenanthrene. When the surfactant solution was applied to EK system, high electrical potential gradient was maintained and the amount of electroosmotic flow decreased. Removal efficiency of phenanthrene was proportional to the concentration of Tergitol 15-S-12 because the solubility and mobility of phenanthrene was enhanced by surfactant micelle. Therefore, the suitable concentration of nonionic surfactant Tergitol 15-S-12 is expected to improve the removal efficiency of PAHs in EK remediation.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 추계학술발표회
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• pp.127-130
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• 2001

This paper presented to phenanthrene removal of electrokinetic(EK) remediation and enhanced EK remediation with bench scale test. The experiments were carried out on mixture soil with phenanthrene as the test compound. The EK remediation experiments were conducted under controlled voltage. Surfactant solution was constantly supplied at the anode reservoir with constant concentration. Results showed that phenanthrene was removed little in EK remediation. Surfactant helped phenanthrene moving and cumulated in cathode region. Moving effect was increased with surfactant concentration.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.543-550
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• 1999

Hazardous substances produced from industrial sectors have caused serious contamination of soils and groundwater. The hydrophobic organic compounds in the subsurface are hard to be decomposed, and as they soil on the soil or last as a NAPL they might contaminate the groundwater for a long time. Although we recognize the danger of contaminated subsurface, very little was known about the effective remediation technique. This paper focuses on the remediation of the p-Cresol which contaminated subsurface by applying the surfactant-enhanced description technique. Sorption characteristics of soils and organic compounds are studied, and the applications of surfactant solution are studied for effective rededication. The results from this study could be used as some data for surfactant-enhanced rededication. The flexible-wall permeameter tests are performed in which in-situ remediation is simulated. Results show that triton X-100 at 2% solution disrobes p-Cresol 1.7 times as much as water description in the flexible-wall permeameter tests.

• 한국지하수토양환경학회지:지하수토양환경
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• 제7권4호
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• pp.3-9
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• 2002

본 연구는 유류 화합물 중 대표적인 소수성 유기 오염물인 phenanthrene으로 오염된 세립질 지반을 실내에서 인위적으로 조성하여 Electrokinetic 정화 처리를 실시하였고, 또한 향상기법으로 계면활성제를 적용하여 정화효율과 거동을 분석하였다. 비향상된 EK 정화 처리에서는 phenanthrene의 이동은 거의 발생하지 않았고, 계면활성제를 이용한 향상기법에서는 양극(+) 근처의 phenanthrene이 음극(-)쪽으로 이동하여 누적되었다. 또한, 계면활성제의 농도가 높을수록 이동 현상이 크게 나타났으며, 시간을 증가할수록 누적된 phenenthrene이 음극(-)저수조로 전기삼투 흐름에 의해 제거되는 것을 알 수 있었다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.51-54
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• 2003

Three kinds of experiments were conducted to test existing methods and develop an effective methodology for the remediation of DNAPL trapped in vertical dead-end fractures. A water-flushing method failed to remove TCE from vertical dead-end fractures where no fluid flow occurs. A water-flushing experiment implies that existing remediation methods, utilizing water-based remedial fluid such as surfactant-enhanced method, have difficulty in removing DNAPL trapped from the vertical downward dead-end fractures, because of no water flow through dead-end fractures, capillary, and gravity forces. Fluid denser than TCE was injected into the fracture network, but did not displace TCE from the vertical dead-end fractures. Base(B on the analysis of the experiments, the increase in the density of the dense fluid and the addition of surfactant to the dense fluid were suggested, and this composite dense fluid with surfactant effectively removed TCE from the vertical dead-end fractures.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권1호
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• pp.13-21
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• 2012

This study reports a surfactant-enhanced in-situ remediation treatment at a test site which is located in a hilly terrain. The leakage oils from a storage tank situated on the top of the hill contaminated soils and groundwater in the lower elevation. Sixteen vertical injection wells (11 m deep) were installed at the top of the hill to introduce 0.1-0.5 vol.% of non-ionic Tween-80 surfactant. The contaminated area that required remediation treatment was about $1,650\;m^2$. Two cycles of injecting surfactant solution followed by water were repeated over approximately 7.5 months: first cycle with 0.5 month of surfactant injection followed by 3 months of water injection, and second cycle with 1 month of surfactant followed by 3 months of water injection. The seasonal fluctuation in groundwater table was also considered in the selection of periods for surfactant and water injection. The results showed that the initial Total Petroleum Hydrocarbon (TPH) concentration of 1,041 mg/kg (maximum 3,605 mg/kg) was reduced significantly down to 76.6 mg/kg in average. After 2nd surfactant injection process finished, average TPH concentration of soils was reduced to 7.5% compared to initial concentration. Also, average BTEX concentration of soils was reduced to 10.8%. This resultes show that the surfactant enhanced in-situ remediation processes can be applicable to LNAPL contaminated site in field scale.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권5호
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• pp.1-7
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• 2016

The removal of non-aqueous phase liquids (NAPLs) from groundwater using pure water, via pump and treat, is quite ineffective due to their low solubility and hydrophobicity. Therefore, the objectives of pilot tests were to select potentially suitable surfactants that solubilize tetrachloroethylene (PCE) and trichloroethylene (TCE) present as contaminants and to evaluate the optimal range of process parameters that can increase the removal efficiency in surfactant-enhanced soil flushing (SESF). Used experimental method for surfactant selection was batch experiments. The surfactant solution parameters for SESF pilot tests were surfactant solution concentration, surfactant solution pH, and the flow rate of surfactant solution in the SESF pilot system. Based on the batch experiments for surfactant selection, DOSL (an anionic surfactant) was selected as a suitable surfactant that solubilizes PCE and TCE present as contaminants. The highest recovery (95%) of the contaminants was obtained using a DOSL surfactant in the batch experiments. The pilot test results revealed that the optimum conditions were achieved with a surfactant solution concentration of 4% (v/v), a surfactant solution pH of 7.5, and a flow rate of 30 L/min of surfactant solution (Lee and Woo, 2015). The maximum removal of contaminants (89%) was obtained when optimum conditions were simultaneously met in pilot-scale SESF operations. These results confirm the viability of SESF for treating PCE and TCE-contaminated groundwater.

• 한국지반공학회논문집
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• 제18권4호
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• pp.349-356
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• 2002

본 연구는 유류 화합물 중 phenol을 대표적인 친수성 유기 화합물로, phenanthrene을 대표적인 소수성 유기오염물로 선정하여 실내에서 인위적으로 오염시킨 세립질 지반에 EK 정화 실험을 실시하였다. 또한, 유기 오염물의 제거효율을 높이기 위해 기존의 양수처리에서 향상기법으로 사용하는 계면활성제를 이용한 향상기법을 연구하였다. 실내 bench 스케일 실험결과, 물에 대한 용해도가 높은 phenol은 비교적 쉽게 제거되었지만, 용해도가 낮은 phenanthrene은 거의 제거되지 않음을 알 수 있었다. 또한, 계면활성제를 적용한 향상기법에서 phenanthrene이 음극부 근처에서 누적되는 지연현상을 보였지만, 농도가 증가할수록 제거효율은 증가하였다. 가동시간을 증가시킨 실험을 통해 시간을 증가시키는 것이 계면활성제의 농도를 증가시키는 것보다 효과적인 것을 알 수 있었다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 창립총회 및 춘계학술발표회
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• pp.149-152
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• 2000

The effects of selected co-surfactants on diesel removal from sandy soil were studied to increase diesel recovery from the soil by the surfactant-enhanced remediation of diesel-contaminated soil. The capability of co-surfactant for enhancing removal efficiency can be related with the interaction between its structural character and the structural peculiarity of nonionic surfactant. In the case of Tween 80, hexanol showed the great improvement in diesel recovery. Efficiency of diesel recovery decreased as hydrocarbon chain length of cosurfactant decreased. Higher content of hexanol further increased diesel recovery, but there was no significant improvement in the case of butanol and pentanol.