• Applied Chemistry for Engineering
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• v.18 no.4
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• pp.391-395
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• 2007

This study investigated the feasibility of enhanced electrokinetic (EK) remediation of soil contaminated with approximately 20000 Pb-mg/kg. Enhanced EK remediation was evaluated by using mixed solution (0.3 M acetic acid and 0.03 M EDTA, EK-M) and by exchanging electrodes for preventing precipitation of metal hydrate. For the EK-M, the lead removal efficiency was only 2% lower than the case where 0.03 M EDTA was solely used (EK-Blank, EK-B). Considering the costly expense of EDTA, the application of EK-M would be economically viable. The efficiency of of EK-E was higher by 2% than the EK-B method. More impertantly, the pH values of entire soil packed column presented to be neutral (7~8) in the EK-E process. Unlike to EK-B and EK-M, the deposition of heavy metals to any specific area was avoided in the EK-E process.

• Journal of Soil and Groundwater Environment
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• v.7 no.1
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• pp.15-24
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• 2002

Nowdays electrokinetic technique has been applied to supply nutrients and TEAs for in-situ bioremediation. However the Injection characteristics under electrical field have not been examined in various soil types. Therefore, The characteristics of electrokinetic injection into kaolinite and sand are investigated. During the 17 d of processing, There was a gradual increase in ammonium (nutrient) concentration from the anode compartment. However the ammonium concentration at the cathode increased beyond that at the anode in sand. A relatively constant profile of sulfate (TEA) was achieved specifically, the final sulfate concentration in each specimen were different. When EK injection technique is implemented in field, the most important consideration should be an assessment of the injection characteristics with respect to the soil types.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.3-38
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• 2002

This paper presents a general review of the literature on electrokinetic (EK) remediation of contaminated soil. Lab-scale tests were investigated and contaminant transport mechanism were examined. And also major factors affecting to the EK process were discussed. Enhanced techniques as a method to solve the problems that frequently occurred during traditional EK process were examined. And last, field implemented case and commercially applied case were described.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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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.

• Journal of Soil and Groundwater Environment
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• v.6 no.4
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• pp.13-23
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• 2001

In this study, the characteristics of pH variations and contaminant distribution in soil are investigated during electrokinetic treatment for the purpose of restoring contaminated soil with heavy metal. For these objects, laboratory test for the kaolin contaminated by lead was performed. During electrokinetic treatment, lead was transported from anode to cathode. And 75% of lead removed within 80% region of the specimen. Most lead, however, that transported from anode to cathode precipitated in the vicinity of cathode compartment, thus the amount of lead removed by electroosmosis was little. Electrokinetic treatment satisfied regulation criteria of Korean Soil Environment Conservation Law within almost region of the specimen. But enhancement methods can be regarded as inevitable requisite for the cathode region.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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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.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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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.

• Journal of Soil and Groundwater Environment
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• v.17 no.4
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• pp.91-97
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• 2012

In this study, cost analysis of electrokinetic (EK) restoration process for desalination of saline agricultural land was performed for field application based on a pilot scale field application. For reasonable cost analysis, EK process was classified into three major parts: system design, installation and operation. Cost of system installation consists of materials and installation for electrode/electric wire, power supply and data monitoring, drainage system, etc. Operation cost was calculated based on electrical consumption and water charges for EK process. Total cost for EK process was 2,943,013 won for $1000m^2$ in greenhouse area. Cost for system installation was 2,553,786 won, that is, 87% of total cost, while cost for system operation was 389,229 won, that is, 13% of total cost.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.76-79
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• 2004

This research was carried out to evaluate role of supplementary reagents, such as phosphate and SDS, to remove hydrophobic organic contaminant from soils during the EK-Fenton process. The $H_2O$$_2$ stability improved due to the role as stabilizer of phosphate and SDS during the EK-Fenton process. Furthermore, although pH in region near cathode was 8.2 after test, $H_2O$$_2$ stability improved due to transportation of SDS in the region near cathode. Therefore, in tests using phosphate and SDS as supplementary reagent, the efficiency of phenanthrene treatment improved through the EK-Fenton process using longer reaction time.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.211-218
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• 2004

The objective of this study is to enhance the ultimate bearing capacity of piles embedded in marine clay by electrokinetic(EK). The focus of improvement is at interlace between soil and pile. A series laboratory test was performed in EK cell. In each of test, the pile in the centre as anode is surrounded by cathode and it was installed in the vicinity of pile with triangular layout. The pile was made by stainless and embedded with 30cm of depth. Afterward, the DC voltage was applied to electrode over period of time. It caused flowing water from anode to cathode, thus the soil in the center of box has higher bearing capacity value than in the side of box has. It is shown by increasing of un-drained shear strength(Cu) near the pile and also ultimate bearing capacity of pile increase after EK treatment. In the future work, the continuous of this study is finding the effective DC voltage and makes EK treatment more applicable in the field.