• 한국지반환경공학회 논문집
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• 제15권4호
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• pp.37-41
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• 2014

펄스동전기법은 점토성-사질토에서 탈수화 공정을 효율적으로 진행하기 위해 제안되었다. 제안된 동전기법은 점토성-사질토에서 토양 안정성의 증진을 위해 전류 흐름에 따르는 유체의 이동에 의한 탈수화 공정을 진행하는 것이다. 제안된 동전기법의 성능을 확인하기 위해 제작된 샘플은 총 7일간에 점진적으로 압력을 증가시켜 30 psi($2.11kgf/cm^2$)의 최종압력으로 압축과정을 거쳐 완성되었다. 기존의 연속적인 처리와 펄스방식으로 처리하는 공정을 비교하여 각각의 특성을 관찰하였다. 각각의 테스트는 48시간 동안 3 V/cm의 전압 경사 조건으로 연속적인 처리공정과 48시간 동안 총 8시간씩 3회에 걸쳐 전기를 차단하는 펄스방식으로 진행하였다. 그 결과, 펄스방식의 효율이 연속처리방식의 효율과 비슷한 것으로 나타났고 펄스방식이 연속처리방식보다 전력소비가 약 50 % 감소로 그 경제성을 입증하였다.

• Membrane and Water Treatment
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• 제11권3호
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• pp.189-193
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• 2020

In this study, electrokinetic remediation equipment was used to remove cesium (Cs) from clay soil and waste solution was treated with sorption process. The influence of electrokinetic process on the removal of Cs was evaluated under the condition of applied electric voltage of 15.0-20.0 V. In addition to monitoring the Cs removal, electrical current and temperature of the electrolyte during experiment were investigated. The removal efficiency of Cs from soil by electrokinetic method was more than 90%. After electrokinetic remediation, Cs was selectively separated from soil waste solution using sorbents. Various adsorption agents such as potassium nickel hexacyanoferrate (KNiHCF), Prussian blue, sodium tetraphenylborate (NaTPB), and zeolite were compared and KNiHCF showed the highest Cs removal efficiency. The Cs adsorption on KNiHCF reached equilibrium in 30 min. The maximum adsorption capacity was 120.4 mg/g at 0.1 g/L of adsorbent dosage. These results demonstrated that our proposed process combined electrokinetic remediation of soil and waste solution treatment with metal ferrocyanide can be a promising technique to decontaminate Cs-contaminated fine soil.

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

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 가을 학술발표회 논문집
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• pp.593-596
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• 2002

This study examined the feasibility of Electrokinetic-Fenton process for remediation of contaminated kaolinite by phenanthrene. The test using 7% H$_2$O$_2$as anode purging solution indicated the higher electrical current and electroosmotic flow than the test using 3.5% H$_2$O$_2$. And distribution in the soil of H$_2$O$_2$concentration showed the higher value of the former than the latter. Furthermore, the test using 7% H$_2$O$_2$and 0.01N H$_2$SO$_4$was the highest electrical current and electroosmotic flow and H$_2$O$_2$was effectively introduced to the cathode region. As it turned out, the treatment effect of phenanthrene was improved in compare with the other tests.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.245-248
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• 1998

Electrokinetic tests are conducted on laver contaminated with heavy metals to investigate the efficiency of the process in removing Cd, Pb, and Zn. The tests were operated at constant current, and operating time were 0 - 24 hours. The removal efficiency in electro-osmosis with open electrodes is time-dependent. The absorbed Cd, Pb and Zn were removed 50.94-95.75%, 80.78-81.96%, and 48.10-83.83% by the process.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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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.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권1호
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• pp.6-15
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• 2013

The influence of processing fluids and electrode spacing on the electrokinetic process was evaluated to remediate As-, Cu-, Pb-contaminated soil. Single and mixture of sodium citrate, EDTA and NaOH was used to investigate the metal extraction. EDTA for washing reagent showed the highest removal efficiency. Based on the extraction result, the electrode spacing (20, 40, 60 cm) on the electrokinetic process was investigated to remove the multi-metals from soil. The highest removal was observed at the experiment with 60 cm of electrode spacing, however, the correlation between electrode spacing and removal of metals was not clear. The electrode spacing influenced the amount of accumulated electro-osmotic flow. BCR sequential extraction showed that electrokinetic process removed the fractionation of metals bound to Fe-Mn oxyhydroxide.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 가을 학술발표회 논문집
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• pp.241-246
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• 1999

In this research, electrokinetic remediation test was experimented with contaminated kaoline specimen at below, above the cation-exchange capacity of the mineral. The changes of the flow in electro-osmosis with open electrodes and current were presented, and lead removal results were evaluated through the extraction test. As a result, it was showed that removal efficiency was 20-30%, 67-87% In the anode As lead transport continues, the lead precipitation within a narrow zone very close to the cathode can go significantly high. This high lead precipitation near the cathode could block the flow path, decrease the conductivity, and thus the electroosmotic flow. The net effect will cause a decrease in the efficiency of electrokinetic processing. Therefore, in this study, citric acid and surfactant solution was used at the cathode as enhancement techniques.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 추계학술발표회
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• pp.61-64
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• 2001

In the remediation of contaminated soil by electrokinetic process, transport characteristics of contaminants are major factors. Pb is highly fixed to entire soil and not moved readily. High concentration of Cd was analyzed in the cathodic section but anodic section's concentration was lower than initial concentration. Although the Cd had high treatment effect, 50% of total mass was concentrated in cathodic section and was not flowed out readily. Most of transported Cd may be adsorbed in the cathodic side soil due to increased pH at adjacent to catholyte.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.326-329
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• 2003

When an electrokinetic process is applied to a HOC-contaminated soil, hybrid types combined with soil flushing, chemical oxidation, and bioremediation are generally used. Especially when the electrokinetic process is combined with bioremediation, the hybrid technology can solve several limits of bioremediation such as low microbial mobility, low soil temperature, and shortage of nutrients in subsurface circumstance. Because microbial surface is charged negatively, the microorganism moves from cathode to anode under electrical field. In this study, mixed culture mainly-consisted by Pseudomonas sp. was applied to remediate pentadecane-contaminated kaolinite with particle size less than 300${\mu}{\textrm}{m}$. This remediation system was named ‘electrokinetic bioaugmentation’ and consisted of model aquifer, electrode reservoirs, bioreactor, power supply, and pump. The mixed culture above 0.5 of optical density in bioreactor was supplied to two reservoirs and penetrated soil when the electric current was applied. To enhance the removal efficiency, the optimal medium composition, electric current, and voltage were investigated.