• Journal of Advanced Marine Engineering and Technology
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• 제35권7호
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• pp.946-956
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• 2011

The main objectives of this study are to analyze the leaked gas dispersion and quantify the potential overpressures due to vapor cloud explosions in order to identify the most significant contributors to risk by using Computational Fluid Dynamics (CFX & FLACS) for gas fuelled ships. A series of CFD simulations and analyses have been performed for the various gas release scenarios in a closed module, covering different release rates and ventilating methods. This study is specially focused on the LNG FGS (Fuel Gas Supply) system recently developed for the propulsion of VLCC crude oil carriers by shipyards. Most of work presented is discussed on the gas dispersion from leaks in the FGS room, and shows some blast prediction validation examples.

• KSBB Journal
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• 제10권5호
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• pp.582-588
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• 1995

해양의 유류유출이 잦은 지역으로부터 crude oil 분해능이 뛰어난 미생물을 분리하여 통정한 결과 Pseudomoans 속으로 판명되였으며, 이를 Pseud$\sigma$ moans sp. CHCS-2로 명 명하였다. 이 균주가 배양 중에 생산하는 biosurf actant의 생생 최적 pH 및 NaCI 농도는 각각 8.0 및 3.0% 였으며, 질소원인 peptone에 영향을 받았다. 2% Kuwait crude oil이 첨가된 배양액을 48, 96, 132시간별로 gas chroma­t tography를 이용, 잔류 oil을 분석한 결과 Kuwait crude oil의 C10-CI4부위에 biosurf actant가 작용하여 분해하였으며, 배양 상층액으로부터 Amberlite XAD-7을 이용한 흡착 chromatography와 Sepha­d dex G-100을 이용한 gel chromatography, 그리고 HPLC를 이용하여 biosurf actant를 분리. 정제한 결과 유화력이 뛰어난 단일 peak를 얻었다. Bio-sur­f f actant 유화력은 $40^{\circ}C$에서 가장 좋았으며, 안정성 은 $30^{\circ}C$에서 $60^{\circ}C$까지의 넓은 온도 범위에서 유지 되었다. 또한, 정제된 biosurf actant를 이용하여 계 연장력에 미치는 영향을 검토한 결과, 상엽적으로 널리 판매되고 있는 Tween 80, Tween 60 그리고 SDS보다 표연장력 저하능력이 뛰어난 것으로 밝혀졌다.

• 해양환경안전학회지
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• 제26권3호
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• pp.262-268
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• 2020

The IMO (International Maritime Organization) has mandated the restriction of SOx emissions to 0.5 % for all international sailing vessels since January 2020. And, a number of countries have designated emission control areas for stricter environmental regulations. Three representative methods have been suggested to cope with these regulations; using low-sulphur oil, installing a scrubber, or using LNG (Liquefied Natural Gas) as fuel. In this paper, economic analysis was performed by comparing the method of installing a scrubber with the method of using low-sulphur oil without installing additional equipment. We suggested plausible layouts and compared the pros and cons of dif erent scrubber types for retrofitting. We selected an international sailing ship as the target vessel and estimated payback time and benefits based on navigation route, fuel consumption, and installation and operation costs. Two case of oil prices were analyzed considering the uncertainty of fuel oil price fluctuation. We found that the expected payback time of investment varies from 1 year to 3.5 years depending on the operation ratio of emission control areas and the fuel oil price change.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 추계학술발표회
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• pp.92-92
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• 2017

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 추계학술발표회
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• pp.169-174
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• 2006

모든 원유 (crude oil)와 제품유 (petroleum product)는 서로 구별되는 탄화수소특성을 가지고 있다. 원유의 경우 산지별로 고유한 특성을 지니고 있으며, 제품유의 경우 같은 유종이라 할지라도 그 원료가 되는 원유의 특성, 생산공정, 생산시기 등에서 차이점이 발생한다. 즉, 생산시기가 동일하다 할지라도 선박의 연료탱크내에 남아있는 잔류유와의 혼합 동에 의해 구별되는 특징을 가지게 되며 이러한 특성을 이용한 기법을 유지문기법(oil fingerprint method) 이라 한다. 본 연구에서는 최근 새로운 유지문기법으로 활용 가능성이 대두되고 있는 2 차원 가스크로마토그래프 (Comprehensive Two Dimensional Gas Chromatography)를 이용하여 기존의 가스크로마토그래프 (GC)와 가스크로마토그래프 질량분석기 (GC/MS) 와의 분석방법 비교 등을 통해 유지문 분석기법의 실효성에 대해서 논하고자 한다.

• 센서학회지
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• 제31권4호
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• pp.266-270
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• 2022

Owing to the rising volume of seaborne trade, oil spills damage the marine environment for over 250 yearly. Thus, various analysis methods such as the Fourier-transform infrared (FTIR), Raman spectroscope, and gas chromatography are used to monitor oil spills at sea, but these methods are expensive. Recently, to reduce operational costs, an underwater fluorometer was adopted. However, this approach is not ideal for the remote sensing of oil spills because the device gets submerged in the sea. In this study, we have designed and developed a monitoring system that uses ultraviolet fluorescence to detect spilled oil or water from a distance, as well as proposed an analyzing method defining based on water Raman signal and QF535. Each fluorescence spectrum of water, oil (crude oil), and Bunker A was obtained using the system, and was calculated and analyzed from the spectrum individually. Based on the results of the analysis, we could successfully identity water and oil at a long distance.

• 한국해양학회지
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• 제20권1호
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• pp.74-82
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• 1985

海洋에 기름이 流出되면 蒸發, 溶解, 酸化 및 미생물 分解等의 영향을 받는다. 그러므로 GC에 의한 탄화수소와 黃化合物을 分析하기 위하여 人工的으로 經時變化 시키면서 시료을 채취하였다. GC분석결과 시료유는 저마다의 독특한 형태의 Chromatogram을 나타내고 있다. 탄화수소 중의 低비점 성분의 Peak는 시간이 경과하면서 감소하고 있다. 그러나 FPD에 의해 黃化合物을 分析한 Chromatogram 은 비교적 經時變化의 영향을 적게 받고있다. GC에 의한 탄화수소 및 黃化合物 分析法은 流出油를 비교 分析하여 汚染源을 識別하는데 重要한 方法이다.

• Ocean Systems Engineering
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• 제8권1호
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• pp.21-32
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• 2018

Due to the escalation in hydrocarbon consumption, the offshore industry is now looking for advanced technology to be employed for deep sea exploration. Riser system is an integral part of floating structure used for such oil and gas extraction from deep water offering a system of drill twines and production tubing to spread the exploration well towards the ocean bed. Thus, the marine risers need to be precisely employed. The incorporation of the strengthening material, fiber reinforced polymer (FRP) for deep and ultra-deep water riser has drawn extensive curiosity in offshore engineering as it might offer potential weight savings and improved durability. The design for FRP strengthening involves the local design for critical loads along with the global analysis under all possible nonlinearities and imposed loadings such as platform motion, gravity, buoyancy, wave force, hydrostatic pressure, current etc. for computing and evaluating critical situations. Finite element package, ABAQUS/AQUA is the competent tool to analyze the static and dynamic responses under the offshore hydrodynamic loads. The necessities in design and operating conditions are studied. The study includes describing the methodology, procedure of analysis and the local design of composite riser. The responses and fatigue damage characteristics of the risers are explored for the effects of FRP strengthening. A detail assessment on the technical expansion of strengthening riser has been outlined comprising the inquiry on its behavior. The enquiry exemplifies the strengthening of riser as very potential idea and suitable in marine structures to explore oil and gas in deep sea.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.205-209
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• 2005

Now a days Automobiles are becoming more important in our life, the study on piston of engine is needed because, piston's cooling and lubrication of piston have an effect on the life and efficiency of engine directly. So, this study is about nozzle part of oil jet for cooling piston in the automotive engine. Piston exposes combustion gas of over $2000^{\circ}C$ and is shocked high pressure at the time of explosion shortly. Furthermore strong friction occurs by high speed rotation. The cooling system is considered from oil jet to piston. The previous system cooled the lower part of piston only. So, efficiency was low. To improve this system, make the oil gallery in the piston, and oil flows into the gallery. The value of oil flow rate into the gallery is important. Consequently, the point of this study is the research of investigation of flow characteristics for variable Re number. This study has been modelled by a commercial CFD code FLUENT, allowing to assess its validity

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.27-28
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• 2006

최근 LNG 연료 시장의 호황에 힘입어 LNG선들이 점차 대형화 추세에 있고, LNG선의 추진 기관 또한 경제성, 환경 영향 등의 주어진 요구 환경에 따라 다양화 되고 있다. 기존의 Steam Turbine Propulsion 외에 Conventional 2-stroke Diesel Engine 및 Dual-fuel 4-stroke Diesel Engine of LNG선의 주 기관으로서 이미 상용화 되었고, 기술적/경제적인 이유로 일반 상선의 주기관으로서는 논외에 있었던 Gas Turbine 또한 일부 Oil Major와 Gas Turbine Maker에 의해 그 적용 가능성이 논의되고 있다. 이에 따라 LNG 선에 Gas Turbine 적용 타당성, 고려 사항 및 적용에 따른 이점과 단점 등을 고찰하였다.