• KSBB Journal
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• 제23권6호
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• pp.479-483
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• 2008

본 실험에 사용된 균주는 유류에서 오염된 지역의 토양 시료로부터 직접 분리 하였는데, 이를 액체 배지에서의 성능 시험을 통해 효과를 확인 후 토양 column에 적용하였다. 토양 column에서의 JP-8 분해는 통기에 의한 자연적인 분해와 미생물에 의해 분해되는 것으로 나뉠 수 있다. 토양 내에 접종된 Rhodococcus fascians이 통기를 시키지 않을 경우에도 토양중의 JP-8의 농도가 감소하여 R. fascians의 JP-8 분해가 통기에 상관없이 이루어지는 것을 알 수 있었다. 통기를 시킬 경우 R. fascians를 접종한 경우에 토양중의 JP-8의 70%가 분해되었다. 토양에서 R. fascians의 생장에 작용할 수 있는 질소원을 첨가한 경우 JP-8의 분해율이 75%로 증가하였다. R. fascians에 의한 JP-8의 분해는 세포의 생장과 밀접하게 관련이 있어서 JP-8의 분해율 향상을 위해서는 R. fascians의 증가가 중요함을 알 수 있었다.

• 공업화학
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• 제28권6호
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• pp.714-719
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• 2017

연료가 혼합된 엔진오일은 차량의 문제(엔진마모, 화재, 급발진 등)를 초래하여, 운전자의 안전을 위협할 수 있다. 본 연구에서는 연료가 혼합된 엔진오일의 다양한 성능을 분석하였다. 분석결과, 연료혼합 엔진오일은 인화점, 유동점, 밀도, 동점도, 저온 겉보기점도가 낮아졌다. 사구법 내마모성능시험에서는 연료가 혼합된 엔진오일이 열악한 윤활성으로 마모흔(wear scar)이 증가하였다. 또한 우리 연구팀은 ASTM D2887 방법을 적용한 고온모사증류시험(SIMDIST, simulated distillation)을 통해 엔진오일 내 연료성분을 분석하였다. SIMDIST 분석결과 연료는 엔진오일보다 짧은 머무름시간을 보였으며, 엔진오일 내 연료성분의 정량분석이 가능하였다. 이 SIMDIST 분석방법을 통해 기존 많은 분석장비, 시료양, 분석시간이 필요한 물성분석법을 대신하여 엔진오일 내 연료 오염여부 및 정도를 효과적으로 판단할 수 있을 것이다.

• International Journal of Railway
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• 제4권1호
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• pp.1-4
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• 2011

In this study, the feasibility of using bioremediation to treat lubricant-contaminated soil around railroad turnouts was investigated. Lubricants used during the maintenance of railroad turnouts can drip onto the ground causing soil contamination. In the laboratory experiments, the residual TPH (Total Petroleum Hydrocarbons) concentration in soil gradually decreased after microorganisms degrading the lubricants were added. Generally, the soil around railroad turnouts is covered by a layer of ballasts. In the column experiments that were designed considering field sites, the removal efficiency of TPH was about 11% after 60 days of cultivation time. In the field experiments, microorganisms were added into the soil periodically, and finally the residual TPH concentrations were reduced to less than 1,700 mg/kg-soil on average. These results indicate that the lubricant in the contaminated soil around railroad turnouts could be efficiently removed through bioremediation method.

• Membrane and Water Treatment
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• 제10권4호
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• pp.313-320
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• 2019

Increasing the concentration of nitrate ions in the soil solution and then leaching it to underground aquifers increases the concentration of nitrate in the water, and can cause many health and ecological problems. This study was conducted to evaluate the vulnerability of Meymeh aquifer to nitrate pollution. In this research, sampling of 10 wells was performed according to standard sampling principles and analyzed in the laboratory by spectrophotometric method, then; the nitrate concentration zonation map was drawn by using intermediate models. In the drastic model, the effective parameters for assessing the vulnerability of groundwater aquifers, including the depth of ground water, pure feeding, aquifer environment, soil type, topography slope, non-saturated area and hydraulic conductivity. Which were prepared in the form of seven layers in the ARC GIS software, and by weighting and ranking and integrating these seven layers, the final map of groundwater vulnerability to contamination was prepared. Drastic index estimated for the region between 75-128. For verification of the model, nitrate concentration data in groundwater of the region were used, which showed a relative correlation between the concentration of nitrate and the prepared version of the model. A combination of two vulnerability map and nitrate concentration zonation was provided a qualitative aquifer classification map. According to this map, most of the study areas are within safe and low risk, and only a small portion of the Meymeh Aquifer, which has a nitrate concentration of more than 50 mg / L in groundwater, is classified in a hazardous area.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권7호
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• pp.1-12
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• 2015

The purpose of this study is to highlight the National Classification System related to cleanup the soil contaminated sites and to provide some guidance to address the priority management rank system before the remediation for Busan metropolitan city. Based on the previous soil investigation data, the quantitative classification of vulnerable areas for soil pollution was performed to successfully manage the contaminated sites in Busan. Ten evaluation factors indicating the high soil pollution possibility were used for the priority management ranking system and 10 point was assigned for each factor which was evenly divided by 10 class intervals. For 16 Gu/Guns in Busan, the score of each evaluation factor was assigned according to the ratio of the area (or the number) between in each Gu (or Gun) and in Busan. Ten scores for each Gu (or Gun) was summed up to prioritize the vulnerable Gu or Guns for soil pollution in Busan. Results will be available to determine the most urgent area to cleanup in each Gu (or Gun) and also to assist the municipal government to design a successful and cost-effective site management strategy in Busan.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.207-210
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• 2004

Effect of electron accepters on anaerobic degradation of petroleum hydrocarbons by an anaerobic sludge taken from a sludge digestion tank in a soil artificially contaminated with 10,000 mg/kg soil of diesel fuel was tested. Treatments of soil with 30 mL of the digestion sludge (2,000 mg/L of vss (volatile suspended solids)) were incubated under several anaerobic conditions including nitrate reducing, sulfate reducing, methanogenic, and mixed electron accepters conditions for 120 days. Treatments with the digested sludge showed significant degradation of diesel fuel under all anaerobic conditions compare to control treatments with an autoclaved sludge and without the sludge. The amount of TPH degradation after 120days incubation was the largest in the treatment with the sludge and mixed electron accepters (75% removal of TPH) followed in order by sulfate reducing, nitrate reducing, methanegenic condition as 67%, 53％, 43%, respectively. However, the rate of TPH degradation in the nitrate- and sulfate reducing condition within 105 days were comparable with that of the mixed electron accepters condition. Microorganisms in each electron acceptor condition were plated on solid mediums containing nitrate or sulfate as sole electron acceptor and several nitrate- and sulfate reducing bacteria showed effective degradation of diesel fuel within 30 days incubations. These results suggest that anaerobic degradation of diesel fuel in soil with digested sludge is effective for practical remediation of soil contaminated with petroleum hydrocarbons.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.368-371
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• 2003

Accidental release of petroleum products from underground storage tank(USTs) is one of the most common causes of groundwater contamination. BTEX is the major components of fuel oils, which are hazardous substances regulated by many nations. In addition to BTEX, other gasoline consituents such as MTBE(methyl-t-buthyl ether), anphthalene are also toxic to humans. Natual attenuation processes include physic, chemical, and biological trasformation. Aerobic and anaerobic biodegradation are believed to be the major processes that account for both containment of the petroleum-hydrocarbon plum and reduction of the contaminant concentrations. Aerobic bioremediation has been highly effective in the remediation of many fuel releases. However, Bioremediation of aromatic hydrocarbons in groundwater and sediments is ofen limited by the inability to provide sufficient oxygen to the contaminated zones due to the low water solubility of oxygen. Anaerobic processes refer to a variety of biodegradation mechanisms that use nitrate, ferric iron, sulfate, and carbon dioxide as terminal electron accepters. The objectives of this study was to conduct laboratory-scale microcosm studies in assessing enhanced bioremediation potential of BTEX and MTBE under various electron accepters(aerobic, nitrate, ferric iron, sulfate) in contaminated Soil. these results suggest that, presents evidence and a variety pattern of the biological removal of aromatic compounds under enhanced nitrate-, Fe(III)-, sulfate-reducing conditions.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권3호
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• pp.14-20
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• 2016

Remediation of crude oil contaminated soil is complicate and hard to apply traditional methods because of its persistency, durability, and high viscosity. Therefore, in this study, the efficiency of crude oil contaminated soil remediation was tested by developing a pilot-scale thermal desorption system using the indirect heating method with an exhaust gas treatment. Under optimal condition drawed by temperature and retention time, the remedial efficiency of crude oil contaminated soil and treatability of exhaust gas were analyzed. Total Petroleum Hydrocarbon (TPH) concentration of crude oil contaminated soil was decreased to 69.7 mg/kg on average and the remedial efficiency was measured at 99.60%. Through the exhaust gas, 86.0% of Volatile Organic Compounds (VOC) was degraded and 97.16% of complex malodor was reduced under the suggested optimum operation condition. This study provides important basic data to be useful in scaling up of the indirect thermal desorption system for the remediation of crude oil contaminated soil.

• 자원환경지질
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• 제26권2호
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• pp.175-185
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• 1993

Soils and dusts collected from Changhang smelter area were analyzed for Cu, Pb, Zn, and Cd in order to determine their dispersion pattern and mode of occurrences, and to investigate the pollution level of heavy metals such as Cu, Pb, Zn, and Cd by smelting activity. The soil pH of Changhang area is in the range of 3.7~8.8, and increased with increasing distance from the smelter site. The particles containing heavy metals are several tens of ${\mu}m$ in diameter, and have well crystal form. Samples collected near the smelter show similar particle properties in size, shape, and composition, which means that they could be originated from the same contamination source. Element couples of Cu, Pb, Zn, and Cd indicate high correlation with each other, which means that Cu, Pb, Zn, and Cd could be originated from the same point source of smelter. Heavy metal contents were decayed to background levels from 2.5 kilometer away from the smelter.

• 자원환경지질
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• 제37권6호
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• pp.613-629
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• 2004

울산지역 지하수의 VOCs 함유 실태와 자연적 저감의 진행을 고찰하기 위해 168개 지하수 관정을 선정하여 유기오염 관련 연구를 수행하였다. 유기오염물에 의한 지하수 오염은 토지이용과 밀접한 관계가 있기 때문에 168개 지하수시료를 농업지역, 산림지역, 공업지역 및 주거 상업지역으로 구분하여 해석하였다. 지하수의 VOCs 분석결과 총 168개 중 65개 지하수에서 1개 성분 이상의 휘발성유기화합물이 검출되었다. 분석항목은 미국지질조사소 NAWQA프로그램에서 선정한 36개의 할로겐지방족 탄화수소와 25개 성분의 석유탄화수소(BTEX등 방향족 탄화수소와 MTBE포함)로 구성된다. 석유탄화수소는 26개 관정의 지하수에서 12개 성분이 검출되었으나 MTBE를 제외하고는 $1.5{\mu}g/L$미만의 낮은 농도를 나타내고 있다. 할로겐지방족 탄화수소는 63개관정의 지하수에서 검출되었으며, 검출된 성분은 11개 성분의 메탄류, 6개 성분의 에탄류, 6개 성분의 에텐류로 구성된다. 그중 메탄류는 $ND\~330{\mu}g/L$의 분포를 보이고, 에탄류는 $ND\~84{\mu}g/L$의 범위를 보이며, DCA, CA등은 $ND\~19{\mu}g/L$ 농도를 보인다. 에텐류는 $ND\~62{\mu}g/L$의 범위를 보이며, PCE, TCE 및 그 분해물들은 $ND\~62{\mu}g/L$의 농도를 보인다. 연구지역은 대부분이 호기성/탈질지대 및 $Fe^{3+}$ 지대로 구성되어 대부분의 방향족탄화수소는 분해가 잘되는 환경이나 염소계지방족 탄화수소는 대부분 생분해 반응이 서서히 일어나는 환경에 해당한다.