• 자원ㆍ환경경제연구
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• 제26권4호
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• pp.499-517
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• 2017

본 연구는 원유 구매자가 원유를 구매함에 있어 이윤율헤징 전략이 항상 헤징하거나 모두 현물 구매하는 전략에 비해 최적의 구매전략이 될 수 있는지 기대목표효용 함수를 이용하여 이론적으로 분석하고 시뮬레이션을 실시하였다. 또한 선물가격이 평균회귀할 때 이윤율헤징이 최적의 전략이 된다는 이론적 증명을 바탕으로 원유 선물가격의 평균회귀성에 대한 실증분석을 수행하였다. 기대목표효용함수에 대한 시뮬레이션 결과, 원유를 구매함에 있어 이윤율헤징 전략을 사용할 경우 다른 전략을 사용해 구매하는 경우에 비해 더 높은 기대효용을 가져오는 것으로 나타났다. 원유 선물가격의 평균회귀성에 대한 실증분석 결과 평균회귀성을 가진다는 것은 입증할 수 없었다. 그러나 이론적 분석과 시뮬레이션 결과, 원유 선물시장에서 이윤율 헤징을 통한 구매전략이 원유 구매의 최적 전략이 된다고 판단할 수 있었다.

• 대한조선학회논문집
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• 제52권2호
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• pp.153-160
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• 2015

Pipelines are one of the most important structures in subsea equipment. It is the main equipment for transportation of crude oil and natural gas to the downstream facilities. Crude oil and natural gas leak will be carry out not only political and financial issues but also pollution to the environment. Inaccurate predictions of corrosion behavior will make hazardous consequences. The serviceability assessment of corroded structures is essential especially for subsea pipelines. As corrosion is concerned, the effects of failure due to significant reduction will make it hard to the pipeline operator to maintain the serviceability of pipelines. In this paper, the serviceability assessment of corroded crude oil pipeline is performed using the industry design code (Shell92, DNV RP F101, ASME B31G, BS 7910, PCORRC) and FEA depending on corrosion area. In last step, the future integrity of the subsea crude oil pipeline is assessed to predict the remaining year in service of crude oil pipelines.

• Environmental Engineering Research
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• 제23권2호
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• pp.175-180
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• 2018

Box-Behnken Design (BBD) under response surface methodology (RSM) was implemented to optimization the operating parameters and assess the removal and recovery efficiencies of crude oil from contaminated soil using subcritical water extraction. The effects of temperature, extraction time and water flow rate were explored, and the results indicate that temperature has a great impact on crude oil removal and recovery. The correlation coefficients for oil removal ($R^2=0.74$) and recovery ($R^2=0.98$) suggest that the proposed quadratic model is useful. When setting the target removal and recovery (>99%), BBD-RSM determined the optimum condition to be a temperature of $250^{\circ}C$, extraction time of 120 min, and water flow rate of 1 mL/min. An experiment was carried out to confirm the results, with removal and recovery efficiencies of 99.69% and 87.33%, respectively. This result indicates that BBD is a suitable method to optimize the process variables for crude oil removal and recovery from contaminated soil.

• 대한가정학회지
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• 제24권1호
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• pp.59-64
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• 1986

The contents of proximate components of the polished adn unpolished Job's tears, Coix agrestis, were determined. And also the phisical and the chemical properties of fatty acids composition and the oxidative rancidity of the crude oil extracted from Job's tears were examined. RESULTS : 1.The contnets of moisture, total ash, crude protein, crude fat, and carbohydrate in Job's tears were shown to be about 9.2%, 2.1~5.0%, 19.5~20.8%, 3.7~7.2%, 60.7~67.0%. 2. The average values of specific gravity, refractive index iodine value, saponification value, acid value of the crude oil extracted from Job's tears were 0.917~0.920, 1.47574, 107~111, 198~199, 1.3~2.0, respectively. 3. The fatty acids composition in the crude Job's tears oil showed oleic acid 48.97~49.97%, linoleic acid 37.33~36.16%, palmitic acid 13.70~13.87%. 4. Generally, the peroxide values and thiobarbituric acid values of the Job's tears oils and control during 40 storage days at 40±1℃ showed very low increase. After 32 days, the peroxide values and TBA values of soybean oil showed higher than those of the Job's tears oils. Conclusively, the Job's tears oils were shown to be more stable than the soybean oil.

• 한국토양환경학회지
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• 제2권1호
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• pp.91-97
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• 1997

원유로 오염된 지반의 지반공학적 연구는 환경적인 문제만큼 중요한 사안이나 국내에서는 이와같은 연구가 거의 연구되어지지 않고 있을 뿐만 아니라 심각도 또한 인지하고 있지 못하고 있다. 본 연구는 지반환경학적인 측면에서 원유로 오염된 사질토의 압축강도 특성, 전단강도 및 일축압축강도의 특성을 통하여 원유로 오염된 모래의 물리적 거동을 파악하였다. 실험결과에 의하면 원유로 오염된 모래지반이 오염되지 않은 지반의 내부마찰각이 간극속에 있는 원유로 인하여 감소하고 있으며 오염도에 따라서 강도정수들 또한 현저한 영향을 보이고 있다. 모래의 압축특성은 오염도에 따라 영향을 받는다. 각 시험에 관한 자세한 결과치는 본 본문에 소개하였다.

• Korean Chemical Engineering Research
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• 제45권2호
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• pp.109-116
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• 2007

기존의 경질유가 고갈됨에 따라 새로운 자원개발이 필요해지고 있다. 석유화학산업의 수요를 충족하기 위하여 중질유 혹은 비투맨 등과 같은 중질원료를 사용하고 있다. 비투맨은 복잡하고 고리가 긴 탄화수소의 일종으로 오일샌드로 부터 얻을 수 있는데, 캐나다 앨버타에 매장되어 있는 오일샌드로부터 약 8,300억 배럴의 오일을 얻을 수 있는 것으로 추정된다. 본 보문에서는 (1) 오일샌드, 비투맨, 중질유의 기본 개념, (2) 오일샌드에서 오일을 뽑아내는 방법들, (3) 업그레이드하여 합성원유(synthetic crude oil)를 만드는 방법, (4) 기술의 경제성 평가 등에 대하여 소개하고자 한다.

• 한국미생물·생명공학회지
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• 제21권1호
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• pp.74-81
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• 1993

저온성 세균 Acinetobacter calcoaceticus A1-1의 유류분해 특성을 연구하기 위해 환경적 요인에 대한 영향을 살펴보았다. 이 세균의 성장율과 유화활성도에 대한 적정 환경조건은 온도 $15^{\circ}C$, pH 7.5, 염분도 0-3, 원유농도 0.1로 나타났고 질소원과 인원의 적정농도는$(NH_4)_2S0_4$과 $K_2HP0_4$, 형태로 각각 0.76 mM, 0.057mM이다. 온도에 따른 A.calcoaceticus A1-1의 유류분해 양상을 개스크로마토그라피로 분석한 결과 $10^{\circ}C$, $15^{\circ}C$에서 대부분의 탄화수소 피크가 감소되어 상당 정도의 유류분해를 관찰 할 수 있었다. 반면 $25^{\circ}C$의 경우에는 120시간 배양한 후에도 원유에 포함된 포화탄화수소 화합물들이 부분적으로만 분해되었다.

• 한국환경과학회지
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• 제17권7호
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• pp.795-799
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• 2008

We have studied bioremediation of effective microorganisms on crude oil spill in Taean, west-coast of Korea. Oil contaminated soil samples were collected on December 14, 2007, seven days after the Hebei Spirit oil-spilled accident. Total petroleum hydrocarbon (TPH) was measured to evaluate the effectiveness of effective microorganisms (EM) which were composed with yeast, photosynthetic bacteria and lactic acid bacteria on oil degradation. TPH concentration before EM treatment was 323.8 mg/kg, whereas TPH concentrations on 2 days after EM treatment and that of control (without EM) was 102.1 mg/kg and 170.6 mg/kg, respectively. On six days after EM treatment TPH was 91.3 mg/kg and that of control was 127.7 mg/kg. Percentages of degraded crude oil were 47.3% without EM and 68.5% with EM, 60.6% without EM and 71.8% with EM on 2 and 6 days after EM treatment, respectively. These results clearly showed that the application of effective microorganisms toward oil-contaminated soil was quite useful to degrade crude oil spill. These results were derived from the effects of biostimulation of microbial media nutrients and bioaugmentation of effective microorganisms. If we carefully apply these effective microorganisms, it can be a useful bioremediation method to recover oil-contaminated marine ecosystems.

• 한국패류학회지
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• 제29권1호
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• pp.23-32
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• 2013

The purpose of this study is to evaluate the effects of oil dispersant and ultraviolet (UV) radiation on the toxicity of crude oil. The toxicity of water-accommodated fraction (WAF) and chemically enhanced water-accommodated fraction (CEWAF) of Hebei Spirit crude oil was investigated in the embryo of the Manila clam, Ruditapes philippinarum with- and without ultraviolet radiation. The WAF and CEWAF with- and without UV radiation affected significantly the embryonic development of R. philippinarum. The EC50s of WAF without UV, WAF with UV, CEWAF without UV, and CEWAF with UV were 2.82, 0.79, 1.60, and 0.45 g/L, respectively. CEWAF was 1.6 times more toxic than WAF. UV radiation increased crude oil toxicity to 3.6 times for both WAF and CEWAF. The oil dispersant and UV radiation did not affect the acute toxicity to the embryo but retarded the period of embryonic development up to 26%. R. philippinarum proved to be a sensitive species to reflect the toxic effects of oil spill combined with oil dispersant and UV radiation. It is suggested that the chemical analyses on the WAF and CEWAF is important for the identification and quantitative explanation of the phototoxic compounds in crude oil.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권5호
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• pp.24-30
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• 2011

Tidal flats which are ecologically sensitive, are hard to remediate once they are contaminated by oil spill accidents. Traditional oil remediation measures focus on removal efficiency, and their improper implementation can adversely affect crude oil contaminated coastal areas and greatly disrupt the structure and functions of crude oil contaminated tidal flats. In this study, the oil degradation due to the implementation of remediation measures naturally enhanced using air and natural oil sorbents was evaluated in the lower strata of tidal flats. The effects of air and natural oil sorbents on oil degradation for two concentration levels (< 500 ppm and > 500 ppm) were tested at artificially contaminated tidal flats. Fifty days after these treatments, the natural oil sorbent treatment showed the lowest total petroleum hydrocarbon (TPH) concentration ($4.46{\pm}1.47%$) at the low concentration level, whereas both air and natural oil sorbent treatments showed high degradation efficiencies at the high concentration level ($29.30{\pm}4.39%$). Although the phosphatase activity decreased for all treatments, there was no significant difference between the decreases for the different treatments; on the other hand, B-glucosidase activities were high for both air and natural oil sorbent treatments. Although degradation efficiencies decreased as the concentration increased, the air provision and natural oil sorbent treatment could be an effective ecological restoration measure for oil contaminated tidal flats while minimizing the environmental impact of the remediation efforts.