• KSBB Journal
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• v.21 no.3
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• pp.175-180
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• 2006

In this study, it could be found that the microbial movement in soil under electric field mainly occurred by electrophoresis and electroosmosis. The contribution of electrophoresis on the microbial mobility and flux was generally higher than that of electroosmosis. In the electrokinetic(EK) bioremediation of a pentadecane-contaminated soil, the microbial population increased simultaneously at anode and cathode regions of the soil specimen because both electrophoresis and electroosmosis affected on the microbial movement. After initial operation, the microbial population was high in order of anode, middle, and cathode regions due to their negatively-charged surface and oxygen generation at anode. However, the uniform contaminant removal was achieved by the microbial movement with two-directionality.

• Environmental engineer
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• s.174
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• pp.22-26
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• 2001

(1) 토양오염의 특성과 현황 - 토양오염은 지하에서 일어나는 오염문제이므로 눈으로 직접 확인하기가 어려울 뿐만 아니라 한번 오염되면 복원을 위해서 많은 시간과 경제적 노력이 필요함 - 우리나라에서는 폐광지대 그리고 공업단지 내 유류 저장시설 주변 토양이 중금속과 유기화합물로 심각하게 오염되어 있는 것으로 나타남 (2) 오염토양 정화기술의 분류와 주요기술 - 오염토양 정화기술은 크게 비원위치 기술과 원위치 기술로 분류되며 각각 물리적, 화학적, 생물학적

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2003.06a
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• pp.8-9
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• 2003

• KSBB Journal
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• v.21 no.3
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• pp.181-187
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• 2006

In this study, problems related with pH control in electrokinetic(EK) bioremediation of phenanthrene contaminated soil were observed, and the effects of pH control methods on the removal efficiency were investigated to search a further application strategy. In a preliminary experiment, it was found out by flask cultivation that a certain sulfate concentration was needed to degrade phenanthrene well using Sphingomonas sp. 3Y. However, when $MgSO_4$ was used as sulfate source in EK bioremediation, the bacterial activity reduced seriously due to the abrupt decrease of pHs in soil and bioreactor by the combination of magnesium and hydroxyl ions. When another strong buffering compound was used to control the pH problem, the good maintenance of the bacterial activity and pHs could be observed, but the removal efficiency decreased largely. When a low concentration of $MgSO_4$ was added, the removal efficiency decreased somewhat in spite of the good maintenance of neutral pHs. With the addition of NaOH as a neutralizing agent, the removal efficiency also decreased because of the increase of soil pH. Consequently the selection of electrolyte composition was a very important factor in EK bioremediation and some sulfate sources suitable for both bacterial activity and contaminant degradation should be investigated.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.1
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• pp.79-89
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• 2005

Forest soils were analyzed on their biological and physicochemical properties for the ecological restoration of burnt forest soil using organic wastes and proper microorganisms. Three kinds of soil samples were collected from undamaged soil(US), naturally restoring soil(NS) and artificially restoring soil(AS). All soil samples were sandy soil and acidic soil, ranged pH 5.34~5.78. Moisture content was higher in the soil of NS region. And the others were similar. Total organic matter and soluble sugar were higher at the surface, generally. Heterotrophic soil microbes were abundant at the surface soil of NS and subsoil of AS. Dehydrogenase, cellulase and phosphatase activities were higher at the NS soil. Especially, Dehydrogenase activity as primary index of soil microbial process showed high correlationship with moisture content(r=0.90, P < 0.05).

• Bulletin of Korea Environmental Preservation Association
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• v.26 no.5_6
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• pp.59-61
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• 2004

Landfarming and a microbial agent were used to treat dilsel-contaminated soil. The microbial agent was applied to the contaminated soil in a concentration of 5$\times$102 cfu/soil(g) and the total amount of microbial agent, 210 l , was sprinkled on the soil four times for 24 days during 50 day-remediation period. The remediation goal, lower than 800mg/kg of TPH, was achieved from 5,707mg/kg of TPH within 50 days. The total number and activity of indigenous microorganisms were increased by 100 times after the microbial agent, Bioil-D, was applied to the contaminated soil.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.7
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• pp.764-769
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• 2006

In the electrokinetic(EK) process, oxygen production by electrolysis was proportional to current density. The dissolved oxygen (DO) concentration in anode tank and bioreactor increased with the circulation rate of electrolyte. The bacterial population in bioreactor rapidly increased by the supplement of current, but the DO concentration deceased by the increased bacterial oxygen consumption. From the results of EK bioremediation for pentadecane-contaminated soil, the bacterial population and removal efficiency at 1.88 $mA/cm^2$ were lower than those at 0.63 $mA/cm^2$. This is because the high oxygen production rate largely increased the production rate of organic acids, which reduced the electrolyte pH and bacterial activity. At 0.63 $mA/cm^2$, the highest bacterial population and removal efficiency could be obtained due to the appropriate oxygen production and small decrease in pH.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.610-613
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• 2005

물리 화학적 원리에 의한 환경오염 정화방법은 종종 낮은 효율을 보이면서 공사비 부담은 큰 것으로 나타나고 있다. 그러나 생물학적 방법들은 이러한 단점들을 극복하면서 토양과 지하수를 정화할 수 있는 대안으로서 그 가능성을 입증하고 있는 실정이다. 그 중에서 생물학적 통풍법은 유류오염지역에 적용하고 있으며 그 원리는 지중 오염지역에 충분한 산소를 공급함으로서 오염성분이 토착 미생물에 의해 제거되도록 하는 것이다. 본 발표는 유류오염 지역에 적용된 생물학적 통풍법의 효율을 평가하여 제시하였다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.164-167
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• 2001

현장에서 채취한 토양을 이용하여 Microcosm test를 실시한 결과 온도 및 수분함량이 높을수록 BTEX 분해율이 증가하는 것으로 나타났으며 산소 농도는 21~32% 정도가 적당하였다. 그러나 BTEX 초기농도가 높은 경우에는 생분해율이 감소하는 것으로 나타났다. Bioventing 공법을 현장에 적용한 결과 OUR(Oxygen Utilization Rate)값은 6.3~16.3%O$_2$/day로 조사되었으며 Biodegradation rate 값은 3.4~8.8 mg hydrocarbon/kg soil/day로 조사되어 생물학적 처리 가능성이 있는 것으로 평가되었다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.219-222
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• 2005

유류로 오염된 토양에 대해 토양경작법(Landfarming)을 적용하여 복원효율을 평가하였다. 복원 초기에는 주로 휘발에 의한 오염물질의 저감이 이루어졌으며, 이 후 미생물성장에 필요한 토양뒤집기와 질소원 영양물질의 공급으로 인해 미생물수가 복원초기에 비해 약 200배 증가하면서 약 30여일 경과 후 초기 20,000ppm에서 복원목표인 TPH의 토양오염우려기준 2,000ppm의 이하인 1,910ppm으로 감소하였다. 시간이 경과할수록 탄소원 섭취기질 부족으로 완만한 오염물질 감소속도를 나타내면서 최종적으로 TPH를 측정한 결과 1,288ppm으로서 제거효율 94%이상을 나타내었다.