• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.06a
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• pp.38-42
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• 1998

Soil venting이 오염토양중 가솔린의 용출거동에 미치는 영향을 정량적으로 예측하기 위하여 가솔린의 휘발과 용해거동이 Raoult의 법칙에 의해 설명되어 질 수 있는지를 평가해보았다. 먼저 순수 가솔린의 용해거동과 휘발거동에 대해 검토해 보고 이후 토양중 가솔린의 거동에 적용하여 보았다. 가솔린성분들의 용해거동은 휘발에 의한 성분조성의 변화와 상관없이 Raoult의 법칙에 의해 비교적 정확하게 예측될 수 있었으며 오차범위는 naphthalene을 제외하고는 최고 $\pm$ 100% 이내였다. 오염토양의 형태로 가솔린이 존재하는 경우에도 Raoult의 법칙에 의해 정확히 예측될수 있었으나 토양중 농도가 초기 20,000 mg/kg에서 1,360 mg/kg로 감소한 경우에는 용출농도가 예측치의 50-70% 수준으로 낮은 경향을 보였다. 한편 soil venting시 휘발에 따른 조성변화를 Raoult의 법칙을 이용하여 산정하고 각 성분조성에 대한 개별물질들의 용출잠재성을 결정하는 모델을 이용하여 실험결과와 비교하여 보았다.

• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.53-60
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• 1998

The influence of venting on the leaching characteristics of pure gasoline and gasoline contaminated soil was studied. The change of leaching characteristics by venting of contaminated soil column could be characterized by two distinct trends : 1) the leaching concentration in TPH-GRO rapidly decreased with evaporation until the evaporation loss became 75% of the original volume. Afterwards, it gradually decreased. 2) the leaching concentrations of individual components showed initial increase followed by gradual decrease. In general, the relative increase of leaching concentration and the venting time to reach the maximum increased with the molecular weight of the components. It should be noted that the decrease of gasoline concentration in the vented air occurs faster than that in the leaching solution. This indicates that, after removing most of the gasoline by evaporation, the focus of the risk assessment for the residual contaminants should be on the groundwater contamination rather than air pollution.

• Journal of Korea Soil Environment Society
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• v.3 no.3
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• pp.11-20
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• 1998

The effects of soil venting on the leaching potential of residual gasoline were characterized by applying a simple multi-component volatilization/dissolution model based on Raoult's law. The validity of Raoult's law in describing dissolution of gasoline was evaluated separately using both pure gasoline and gasoline contaminated soil. The aqueous concentrations of gasoline components equilibrated with pure gasoline could be described by Raoult's law within one order of magnitude, regardless of the composition of the gasoline. The leaching concentrations from contaminated soil could be well predicted at a relatively high gasoline concentration in soil. However, after 93.5% removal of gasoline by venting, the calculated values were higher than the experimental values by 50∼100%. A model involving multi-component evaporation and dissolution was applied and the results were compared with the experimental values. Possible causes of the discrepancy between the predicted values and experimental values were given.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.1
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• pp.37-43
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• 1998

Batch experiments were conducted to study the dissolution behavior of gasoline components. First, the dissolution kinetics of gasoline components and the applicability of Raoult's law in predicting their solubilities were investigated. In addition, the effects of compositional change of gasoline due to evaporization on the solubilities of individual components and TPH were determined. The kinetics of gasoline-water man transfer was found to be very similar for most components except for MTBE, which is a major additive for commercial gasoline. At equilibrium, the gasoline-water partitioning coefficients of individual components showed a log-linear relationship with their pure solubilities, though the slope was a little less than that predicted by Raoult's law. The concentrations of the individual components in the gasolines concentrated by volatilization could be characterized by the initial increase followed by substantial decrease. Almost the same behavior was observed for their solubilities. The total solubility (TPH) of gasoline decreased rapidly with the initial volume reduction and gradually decreased afterwards. The solubilities of BTEX, the major regulatory compounds, decreased even faster than the TPH solubilities. It was concluded that the compositional change of gasoline by volatilization may greatly affect their leaching potential and the toxicity of the contacting groundwater. The toxicity reduction efficiency by evaporating gasoline could be much more than the mass removal efficiency.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.65-66
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• 2003

일반적으로 가솔린 VOC의 회수 기술로는 흡착법, 흡수법, 막분리법, 심냉분리법 및 이들의 조합 공정 등이 적용 가능한 것으로 알려져 있다. 본 연구에서는 가장 실용화 가능성이 클 것으로 예상되는 저유소 가솔린 출하설비를 대상으로 하고 있는데, 엄격한 배출 기준을 충족하면서 운전비용과 장치비용면에서 흡착법이 가장 경제적인 공정으로 선정되었다. 저유소에서 배출되는 오염공기량은 시간대별 가솔린출하량, 출하설비 수(loading bay), 일일 최대 가솔린 부하량에 따라서 달라진다. 가솔린 배출 시간은 출하 일정에 따라 불규칙하게 변동되며 산발적인 특징이 있다. (중략)

• Journal of Soil and Groundwater Environment
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• v.9 no.2
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• pp.28-40
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• 2004

Box experiments were performed to evaluate the removal efficiency of SVE (soil vapor extraction) for gasoline in soil. An activated carbon sorption tower and a biofilter were operated as post-treatment processes to remove VOCs extracted from extraction wells of SVE. An acrylic resin box (65 cm${\times}$20 cm${\times}$30 cm) was used to make artificial soil layers and two injection wells and one extraction well were built for SVE process in the box. Gases from extraction wells flew into the activated carbon sorption tower or the biofilter. Gasoline concentrations of VOCs emitted from the extraction well were compared with those after post treatments. More than 92% of initial gasoline mass in soil were removed by SVE within few days, suggesting that SVE is very available to remove VOCs from contaminated soils. To treat VOCs from extraction wells of SVE, an activated carbon sorption tower and a biofilter were attached to SVE process and their gasoline removal efficiencies were measured. These post treatment systems lowered gasoline concentrations to below 1.0 ppm within few days. Average remediation efficiency was 98% of gasoline for the activated carbon sorption tower and 84.1% for the biofilter. The maximum removal capacity of a biofilter was 10.7 g/L/hr, which was ten times higher than general biofilter removal capacity. Results from the study suggest that the activated carbon sorption tower and the biofilter would be available for the post treatment process to remove VOCs generated from SVE process.

• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.3-12
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• 1998

To analyze of oils in contaminated soils, it is necessary to classify of oils accurately and it has to be selected suitable extraction method and instrumental analysis method in according to the character of sample. In this study, oils are classified into three groups-gasoline, diesel and kerosene-we consider extraction methods and quantitative analysis method of these oils using GC/MS. As the analysis example of real sample, we analyze some gasolines and diesels of some oil refining company and calculate BTEX in gasoline and saturated n-hydrocarbons in diesel. And also, we study the representative quantitative method of each kind of oils.

• Journal of the KSME
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• v.19 no.2
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• pp.106-112
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• 1979

70년대초만 하여도 디이젤기관의 배출가스에 대해서는 일반적으로 그렇게 문제시 인식되지 않 았다. 다만 우리들 감각으로 흑연이 나오니까 CO가 많겠고, 특유의 주기가 있으니 HC가 많지 않 을까\ulcorner 하는 정도 였었다. 또한 가솔린 기관에 비하여 유해배출가스가 비교적 적기 때문에 그에 대한 연구도 눈에 띄게 진전하지 않았다. 공해의 선진국이라 말할 수 있는 미국. 일본에서도 가솔린기관의 규제보다 5,6년 늦어, 캘리포오니아주에서는 1973년에 제안하여 규제가 시작되었고, 일본에서도 디이젤기관의 본격적 오염도 규제가 1975년부터 시작하였다. 그러나 최근 가솔린 기관의 배출가스 공해문제의 해결대책이 극한에 달해 가고 있고, 도시인구의 대량집중화 및 수 송화물차량의 급증으로 디이젤차량(Bus, Truck 등)의 교통수단이 증대 일로에 있다. 이에 따라 디이젤기관의 배출가스의 대책도 심각하게 되어 연구가 활발하게 이루어져 가고 있다. 따라서 본 소고에서는 디이젤기관의 오염물질배출기구와 배출가스에 영향을 주는 제요소 및 그 대책에 대 하여 개괄적으로 간단히 살펴보기로 한다.

• Journal of the korean Society of Automotive Engineers
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• v.18 no.6
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• pp.33-39
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• 1996

최근 서울의 일부 지역에서는 오존 주의보에 의한 대기 오염의 수치가 발표되고 있어 이의 심각성이 대두되고 있다. 대기오염의 주범은 자동차이며, 자동차에서 주로 많이 배출되는 질소산화물(NOx)과 탄화수소(HC) 및 디젤자동차에서의 입자상 물질(PM: Particulate Matter)등이 대기환경에 미치는 영향이 크므로 이러한 물질의 저감에 대한 요구가 점차 강화되어가고 있다. 특히, 디젤 엔진이 가솔린 엔진에 비해 대기오염의 주원인이라는 편견이 일반적으로 널리 알려져 있지만, 이는 눈에 보이는 Black smoke에 대한 거부반응이 있다는 점이다. 실제로 디젤 엔진의 유해 배출 성분 중에서 NOx는 가솔린과 비슷한 수준이나 HC와 CO성분은 상당히 적게 배출되고 있다. 또한, 디젤 엔진은 연료 경제성 및 지구 온난화의 원인인 CO$_{2}$ 배출이 적다는 장점이 있으므로 디젤 엔진에서 많이 배출되는 성분으로서 입자상 물질(PM) 및 NOx를 줄이는 방안이 요구되고 있다. 이를 저감시키는 방법은 여러가지가 있으나 분사계 측면에서 전자제어식 고압 연료 분사가 요구되고 있으며 이의 개발 필요성에 대해서 논하기로 한다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1999.04a
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• pp.29-30
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• 1999