• Journal of the Korean Institute of Gas
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• v.20 no.3
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• pp.46-51
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• 2016

Natural gas liquefaction process which spends a huge amount energy is operated under cryogenic conditions. Thus, many researchers have studied on minimizing energy consumption of LNG plant. However, a few studied for cost optimization have performed. This study focused on the cost analysis for the single mixed refrigerant (SMR) process, one of the simplest natural gas liquefaction process, which has different capacity. The process capacity is increased from 1 million ton per annum (MTPA) to 2.5 MTPA by 0.5 MTPA steps. According to the increase of plant size, only flow rate of natural gas and mixed refrigerant are increased and other operating conditions are fixed. Aspen Economic Evaluator(v.8.7) is used for the cost analysis and six tenths factor rule is applied to obtain multi stream heat exchanger cost data which is not supplied by Aspen Economic Evaluator. Moreover, the optimal plant sizes for different sizes of gas wells are found as the result of applying plant cost to small scale gas wells, 20 million ton (MT), 40 MT, and 80 MT. Through this cost analysis, the foundation is built to optimize LNG plant in terms of the cost.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.721-722
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• 2010

• 전기의세계
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• v.44 no.4
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• pp.31-41
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• 1995

본 논문에서는 바다 한가운데를 매립하여 만든 인공섬 위에 부식영향에 취약한 지역에 나관상태로 매설되는 액화 천연가스 탱크기초 강관파일에 전기방식을 적용하는 사례를 통하여 전기방식관련 자료검토와 현장예비조사를 통한 적정한 전기방식설계 적용, 전기방식 전위측정 시험방법, 방식설비 주위시설물에 대한 간섭영향등을 논술하였다.

• Journal of the KSME
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• v.50 no.9
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• pp.43-46
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• 2010

석탄가스화 기술은 석탄가스화복합발전(IGCC), 석탄의 간접액화, 석탄합성가스를 사용한 메탄올 등 화학원료 생산, 천연합성가스(SNG) 생산에 핵심 되는 기술이다. 석탄가스화 기술의 역사는 100년이 넘었지만 현재 사용되는 기술은 반응시간과 규모, 온도 압력 측면 등에서 전혀 다르다. 석탄가스화 기술의 간략한 역사와 최근 석탄가스화 업계 동향, 석탄가스화 분야에서 추진되고 있는 미래기술의 방향을 소개한다.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.151.1-151.1
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• 2010

Natural gas hydrates (NGH) provide 170 gas volumes per unit volume of the medium and are easier to make with moderate pressure and temperature (40 bar at 3 C). Once they form, their preservation temperature is 20 C at 1 bar, which is much milder than the LNG preservation. In case of using the NGH, The small and medium sized gas well has advantages for development because of NGH's these characteristics. According to the cost evaluation report of Gudmundsson in Norway and the research of MES in Japan, the gas well that uses the NGH has a cost saving effect about 10~20% compared LNG. The effect depends on distance and production. However, cost saving and efficiency of liquefaction process is increased by the development of LNG liquefaction technology. Therefore, these factors have to be reflected in economic analysis. The purpose of this research is to compare the cost of Gas Supply Chain according to the transport type, distance and gas reserves. Especially, we consider not only the cost of facility but also the total cost (production cost, transport cost, etc).

• Journal of the Korean Institute of Gas
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• v.20 no.1
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• pp.7-12
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• 2016

Natural gas liquefaction process is essential to transport natural gas for long distances. Lots of compressors in this process are needed and the energy for these compressors can be supplied by drivers. Total driver cost can be changed by selecting various drivers. This study focused on the minimization of the driver cost to provide the energy to the compressors. Moreover, scenarios, extracting velocity is changed during whole operating period, are set with considering gas well capacity. The mathematical model was established by considering trade off relationship between the capital cost and the operating cost of the turbines. The model also considers the life time of the driver equipments. As the result, the driver cost of the optimized case was reduced by 6.4% than the base case.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2001.11a
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• pp.281-286
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• 2001

우리나라는 석유가 나지 않는 비산유국으로서 거의 모든 에너지 자원을 막대한 외화를 지급하여 수입하고 있는 실정이다. 이렇게 수입되는 에너지원중에서 대기 오염 등의 환경문제가 대두되면서 액화 천연가스가 청정에너지로 두각을 나타내게 되었으며, 국내에서는 도시가스로 보급되어 수요가 점차적으로 계속 증가하고 있는 추세이다 기체상태로 기화된 천연가스는 일반 가정이나 산업체에 관로(pipe line)를 통하여 공급되는데, 이들 가스배관은 대부분 지하에 일정한 깊이로 매몰되어 설치된다.(중략)

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.1
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• pp.22-28
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• 2013

The heat transfer characteristics of LNG(Liquefied Natural Gas) vaporizer on the ship was performed by numerical simulation to get the optimum NG(Natural Gas) generating condition. The glycol-water was used for heating in LNG vaporizer, and the cooling water of main engine was used as heating souse for glycol-water. This cooling water temperature increases again after recirculating from the main engine, and then it can be used to heat the glycol-water. The numerical analysis results has good agreement with the experimental results by liquid nitrogen for validation. So CFD technique was used to simulate the heat transfer characteristics of LNG vaporizer on the ship. The numerical results show that the operation condition of LNG vaporizer shows NG temperature of $6^{\circ}C$ in the outlet of LNG vaporizer, and the mass flow rates of LNG and glycol-water were showed 0.111 kg/s and 1.805 kg/s, respectively.

• Journal of the Korean Institute of Gas
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• v.5 no.3 s.15
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• pp.23-28
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• 2001

BOG(Boil Off Gas) is formed about 0.05 vol$\%$/day from LNG tanks of LNG receiving terminal. To recycle the BOG using LNG cold energy, the quantities of LNG and BOG is mixed at the ratio of 11 : 1 by mass in the recondenser of mixing drum type. However, this process is inefficient in the view of energy. It is the most necessary for improvement BOG recondensing process to reduce LNG quantities supplying to recondense system. Therefore, this study has aimed to propose heat exchanger type and suggest results through the analysis of ASPEN PLUS simulator and feasibility study.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.5
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• pp.632-637
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• 2010

Natural gas, a fossil fuel contained mostly of methane, is one of the cleanest alternative fuels. It can be used in the form of compressed gas(CNG) or liquefied natural gas(LNG) to cars and trucks. And, dedicated natural gas vehicles are designed to run on natural gas only, while Bi-fuel vehicles can also run on gasoline or CNG, especially, bi-fuel can be defined as the simultaneous combustion of two fuels. In this study, converted gasoline marine system to CNG Bi-fuel system which is made up of injector, regulator, tank and ECU is converted. And estimated the fuel system and engine power compared the result with gasoline engine is estimated. As a result, CNG engine shows low exhaust emissions but maxium power is 7% reduced compared to gasoline engine.