• 한국환경보건학회지
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• 제22권3호
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• pp.116-122
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• 1996

This study has been focused on the applicability of microwave treatment of soil contaminated by volitile organic chemicals. Substrates studied were sand and sandy soil. These substrates were impregnated with toluene, tetrachloroethylene, o-xylene and p-dichlorobenzene. The microwave treatment was conducted in a modified domestic microwave oven: 2450 MHz, 700 W. The sandy soil temperature added water went up rapidly to about 130$\circ$C for 4 minutes. And then, the temperature appeared to plateau out. A series of tests were performed to depict the effectiveness of microwave treatment technique to organic contaminants from soils. Removal efficiencies in sandy soil and sand were increased with increasing water content and exposure time. Microwave radiation penetrates the soil and heats water throughout the matrix. Therefore, addition of a certain amount of water to the contaminated soil can efficiently enhance the ability of the soil to absorb microwave energy and promote the evaporation of the volitile contaminants. And the vapour pressure of impregnated organic contaminants becomes lower. the removal efficiency becomes poor.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권3호
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• pp.73-81
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• 2013

Various remediation methods have been applied to clean soils contaminated with pollutants. They remove contaminants from the soils by utilizing physicochemical, biological, and thermal processes and can satisfy soil remediation standards within a limited time; however, they also have an effect on the biological functions of soils by changing soil properties. In this study, changes of the biological properties of soils before and after treatment with three frequently used remediation methods-soil washing, land farming, and thermal desorption-were monitored to investigate the effects of remediation methods on soil biological functions. Total microbial number and soil enzyme activities, germination rate and growth of Brassica juncea, biomass change of Eisenia andrei were examined the effects on soil microorganisms, plant, and soil organisms, respectively. After soil washing, the germination rate of Brassica juncea increased but the above-ground growth and total microbial number decreased. Dehydrogenase activity, germination rate and above-ground growth increased in both land farming and thermal desorption treated soil. Although the growth of Eisenia andrei in thermal desorption treated soil was higher than any other treatment, it was still lower than that in non-contaminated soil. These results show that the remediation processes used to clean contaminated soil also affect soil biological functions. To utilize the cleaned soil for healthy and more value-added purposes, soil improvement and process development are needed.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1463-1474
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• 2008

In order to investigate stabilization effect and sustainability on As-contaminated farmland soils which were affected the abandoned mine site and stabilized by zerovalent iron(ZVI) and industrial by-products, batch-scale and pilot-scale tests were carried out. In batch tests, ZVI and industrial by-products(blast furnace slag, steel refining slag and oyster shell powder) were used in treatment materials to reduce the As leaching. Industrial by-products were mixed with As-contaminated soils, in the ratio of 1%, 3%, 5% and 7% on the weight base of dried soil. The results of batch-scale tests was shown that the reduction of As concentration was observed in all samples and it was expected that ZVI and steel refining slag were more effective than other treatment materials to stabilize As compounds. In pilot-scale tests, columns were filled with untreated soils and treated soils mixed with ZVI and steel refining slag in the same mixing ratio of 3%. Distilled water was discharged into the columns with the velocity of 0.3 pore volume/day. During the test, pH, EC, Eh and As concentration were measured in the regular term(1pore volume). after six months, pilot-scale tests were retested to investigate sustainability of treatment materials. As a result, It was shown that the leachate from control column was continuously released during the test period and its concentration was greater than $100ug{\cdot}L^{-1}$ which was exceeded the national regulation of water discharged to river or stream ($50ug{\cdot}L^{-1}$). On the other hand, soil treated with ZVI and steel refining slag showed that the concentrations of leachate were lower than national regulation of water discharged to river or stream. Therefore it was expected that ZVI and steel refining slag could be applied to the farmland site as the alternative treatment materials.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.401-406
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• 2000

Spilling of petroleum hydrocarbons such as gasoline, motor oils, and diesel fuel from underground storage tanks (USTs) is a major source of contamination to ground water and soils. In response to the need of developing an effective and economical cleanup technique, this study investigates the effectiveness of using sonication to enhance the soil flushing method. The study involves laboratory testing, and the testing was conducted using a specially designed and fabricated device to determine the effect of sonication on contaminant removal. The sonication was applied at 20 kHz frequency under different power levels. Test soil was Joomoonjin Sand, and diesel fuel was used as a contaminant of soil flushing test. The results of the investigation show that sonication enhanced the contaminant removal from soils significantly, and the degree of enhancement varied with power levels of sonication. Based on the results of the study, it is concluded that the flushing method with sonication has a great potential to become an effective method for removing petroleum hydrocarbons from the contaminated ground.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1512-1517
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• 2008

Laboratory column tests were conducted in this study using $Cl^-$ tracers on Jumunjin sand to analyze contaminant transport in mixed contaminated soils. Results obtained from clean soils and soils containing residual diesel verified heterogeneous distribution of residual diesel, and clear acceleration of solute movement. In addition, asymmetric breakthrough curves indicated development of immobile region where solute movement becomes stagnant and creates tailing phenomenon.

• 한국지하수토양환경학회지:지하수토양환경
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• 제25권1호
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• pp.62-73
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• 2020

PAHs commonly found in industrial sites such as manufactured gas plants (MGP) are potentially toxic, mutagenic and carcinogenic, and thus require immediate remediation. In-situ chemical oxidation (ISCO) is known as a highly efficient technology for soil and groundwater remediation. Among the several types of oxidants utilized in ISCO, persulfate has gained significant attention in recent years. Peroxydisulfate ion (S₂O₈^2-) is a strong oxidant with very high redox potential (E⁰ = 2.01 V). When mixed with Fe²⁺, it is capable of forming the sulfate radical (SO₄^-·) that has an even higher redox potential (E⁰ = 2.6 V). In this study, the influence of various iron activators on the persulfate oxidation of PAHs in contaminated soils was investigated. Several iron sources such as ferrous sulfate (FeSO₄), ferrous sulfide (FeS) and zero-valent iron (Fe(0)) were tested as a persulfate activator. Acenaphthene (ANE), dibenzofuran (DBF) and fluorene (FLE) were selected as model compounds because they were the dominant PAHs found in the field-contaminated soil collected from a MGP site. Oxidation kinetics of these PAHs in an artificially contaminated soil and the PAH-contaminated field soil were investigated. For all soils, Fe(0) was the most effective iron activator. The maximum PAHs removal rate in Fe(0)-mediated reactions was 92.7% for ANE, 83.0% for FLE, and 59.3% for DBF in the artificially contaminated soil, while the removal rate of total PAHs was 72.7% in the field-contaminated soil. To promote the iron activator effect, the effects of hydroxylamine as a reducing agent on reduction of Fe³⁺ to Fe²⁺, and EDTA and pyrophosphate as chelating agents on iron stabilization in persulfate oxidation were also investigated. As hydroxylamine and chelating agents (EDTA, pyrophosphate) dosage increased, the individual PAH removal rate in the artificially contaminated soil and the total PAHs removal rate in the field-contaminated soil increased.

• 자원환경지질
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• 제40권1호
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• pp.15-28
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• 2007

이 연구에서는 보은제일광산 주변 밭토양의 오염정도를 주원소, 희토류원소 빛 미량원소를 이용하여 접근해보았다. 이들 연구결과는 충주, 덕평, 보은 및 추부지역의 것들과 비교되었다. 주성분 원소 중 Fe와 S는 비오염예상지역, 충주 및 보은지역 밭토양의 원소보다 높았다. 오염예상지역에서의 미량윈소는 비오염예상지역, 충주, 덕평, 보은 및 추부지역의 함량보다 높았다. 이들 원소들은 상관성과 분산을 기초로 U, Cd, Ni, Sr, V, Zn 등의 원소들과 As, Co, Cu, Mo, Pb, Sb 등의 원소들로 구분되며 두 그룹의 원소들은 원소간에 양의 상관성을 갖는다. 잠재적 독성윈소들의 부화 계수는 오염예상지역에서 5 이상의 값을 갖으며 비오염예상지역에서는 4 미만의 값을 갖는다. 오염예상지역에서 As, Cd, Co, Cu, Mn, Ni, U 및 Zn 원소의 지누적지수는 1 이상의 값을 갖으며, 비오염예상지역에서는 Mn원소를 제외한 모든 미량원소가 1 미만의 값을 갖는다. 잠재적 독성원소에 대한 부화지수에서 오염예상지역($0.3{\sim}87.0$)과 비오염예상지역($0.4{\sim}3.9$)은 차이를 보였다. 전체적인 오염예상지역 밭토양내 원소들(Fe, S, As, Cd, Co, Cu, Ni, U, Zn)의 높은 함량은 광산활동에 의한 오염을 지시한다.

• 한국토양환경학회지
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• 제4권2호
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• pp.127-136
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• 1999

식물을 이용하여 토양이나 지하수 등의 매질로부터 오염물을 제거하는 기술인 phytoremediation은 지난 몇 년간 확용잠재성이 높은 환경복원기술로 많은 관심을 받아왔다. 본 연구에서는 현장조건을 모사한 그린하우스에서 이러한 phytoremediation에 의한 디젤로 오염된 토양의 정화효과를 조사하였다. 처리실험에 적합한 식물을 선정하기 위하여 인위적으로 디젤로 오염시킨 토양에서 증가에 따른 대상식물인 알팔파 옥수수, 피, 물피의 생장율 저하정도를 관측하여 내성이 강한 알팔파를 정화식물로 이용하였다. 디젤오염토양의 처리실험은 공기주입, 알팔파 파종, 공기주입과 알팔파 파종이 함께 적용된, PVC 파이프형태의 처리구에서 오염토양의 정화정도를 약 100일간 관측하였다. 칼럼 실험결과, 오염물의 제거속도에 기여하는 식물의 긍정적 효과가 관측되었으며 또한 지속적으로 토양내로 공기를 공급 하여줌으로써 Phytoremediation의 처리효율을 더욱 향상시킬 수가 있었다. 실험종료 후 각각의 처리구에서 토양 깊이별 미생물의 활성을 간접적으로 측정한 결과, 이러한 식물의 정화효과는 근권에 있는 토양미생물에게 유용한 뿌리 분비물을 지속적으로 제공함으로써 미생물의 활발한 번식 및 분해활동을 유지시켜 오염물의 분해를 더욱 촉진시키는 것으로 보인다.

• 한국미생물·생명공학회지
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• 제49권3호
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• pp.413-424
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• 2021

식물과 근권미생물을 이용해 토양 오염물질을 제거하는 rhizoremediation의 효율을 높이기 위해서는 오염물질을 제거함과 동시에 식물 생장을 촉진시키는 미생물 자원 개발이 필요하다. 본 연구에서는 중금속 및 유류 복합 오염 토양에서 서식하고 있는 옥수수와 톨페스큐의 근권으로부터 중금속(구리, 카드뮴 및 납) 내성을 가진 근권세균을 순수분리하였고, 식물 생장 촉진능, 중금속 내성능 및 디젤 분해능을 정성적으로 평가하였다. 그 결과 중금속 내성, 식물 생장 촉진 활성 및 디젤 분해능을 가진 6종의 균주를 분리하였다. 옥수수 근권에서 분리한 CuM5와 CdM2 균주는 Cupriavidus sp.로 동정되었다. 톨페스큐 근권에서 분리한 CuT6, CdT2, CdT5 및 PbT3는 각각 Fulvimonas soli, Cupriavidus sp., Novosphingonium sp. 및 Bacillus sp.로 동정되었다. Cupriavidus sp. CuM5와 CdM2는 중금속 내성과 디젤 분해능은 상대적으로 낮았으나, 식물 생장 촉진능이 상대적으로 우수하였다. 6종 중에서 디젤 분해능이 가장 우수한 균주는 Cupriavidus sp. CdT2와 Bacillus sp. PbT3이었다. 특히, Bacillus sp. PbT3는 3종의 중금속에 대해 상대적으로 우수한 내성을 가졌고 식물 생장 촉진능도 우수하였다. 본 연구에서 분리한 근권세균은 유류와 중금속 복합 오염 토양을 정화시키며 식물 생장을 촉진시키는 새로운 미생물 자원으로 활용 가능하다.

• 자원환경지질
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• 제36권6호
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• pp.469-480
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• 2003

용출실험 연구는 서보 및 청양광산의 광미와 오염토양이 산성비(pH 5.0∼3.0)또는 강한 산성용액(pH 2.5∼l.0)과 반응하였을 때 용출될 수 있는 중금속의 함량을 예측하기 위하여 실시되었다. pH 5.0∼3.0인 용액에서, pH가 낮아질수록 광미 내 비소, 납, 아연의 용해도는 많이 증가하였다. 반면에 토양에서의 중금속의 용해도는 매우 제한적이었다. 이와 같은 결과로부터 산성비에 의하여 광미 내 납, 비소, 아연은 용출되나, 토양 내 이들 원소들은 고정되어 있음을 알 수 있다. pH 2.5∼l.0인 강한 산성과 반응시에는 pH가 낮아질수록 오염된 토양 내 아연, 카드뮴, 구리의 농도가 급격히 증가하는 반면, 광미 내에서는 납, 비소, 코발트의 용해도가 매우 증가한다 한편, CY4(청양광산)를 제외한 광미 내 아연, 카드뮴 및 구리의 용해도는 매우 낮은 pH(약 pH 1)에서 조차 낮은 용해도를 보여준다. 이것은 불완전 용해 또는 불용성의 광물상의 존재에 기인한다. 따라서 중금속의 용해도는 반응 용액의 pH뿐만 아니라 광미 및 오염토양 내 존재하는 금속의 존재형태에 영향을 받음을 알 수 있다. 반응용액의 pH가 5.0∼3.0인 경우, 광미에 함유된 원소들 간의 상대적인 이동도는 Pb>Zn>Cd)Co=Cu＞As이었다. 반응용액의 pH가 2.5∼l.0사이인 경우, 금속원소들의 상대적인 이동도는 오염 토양의 경우 Zn＞Cd>Cu≫Co>Pb=As이고, 광미로부터는 Pb≫Zn>Cd>As>Co>Cu이었다. 이러한 연구결과들은 이 지역에서 광산 폐기물의 환경적 영향에 대한 평가를 가능하게 하고, 복원 계획에 대한 유용한 자료로 사용될 수 있다.