• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5D
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• pp.473-481
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• 2012

Demand of Natural Gas (NG) consumption is continuously increasing by long service life and low environmental impact than other fossil fuels. Because of this reasons, Gas wells exploration and huge LNG plant construction project are being boosted world-widely. Especially, overseas NG pipe-line projects are emerging by considering safe and efficiency at the inter-country sections. At the same time, Korean contractors are being achieved to record-breaking performance at 2011's overseas construction market and 80% of new-record was attained from overseas plant construction projects. Nevertheless, Korean contractors are behind than overseas leading contractors by geographical distance from gas wells and concentrated demand for storage plant. In these reasons, this paper aims to develop the standardized business process model(BPM) for overseas NG pipe-line project at project planning phase to support the project entry. To this aim, first of all, extract the BPM through the broad literature and overseas construction market review and domestic/overseas pipe-line project analysis. Second, Test-bed was performed to confirm of practical applicability by 4 experts. And then 15 experts survey were performed to validate the usability and effectiveness of BPM for overseas NG pipe-line project. Consequently, if Korean contractors are using this BPM with their own know-how and experiences, it will be returned to more reasonable and rational references for decision making in overseas NG pipe-line project.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.730-736
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• 2019

The demand for natural gas, which is considered an environmentally friendly energy source, is increasing, and at the same time, the market share of large pipelines for natural gas supply is increasing continuously. On the other hand, the corrosion of such large pipelines reduces the efficiency of natural gas transportation. Therefore, this study aims to establish a strategy for securing the patent rights of related technologies through quantitative analysis of patents on energy-independent high-efficiency corrosion prevention technology for large-scale pipelines for natural gas supply. In this patent technology trend study, Korean, US, Japanese, and European patents filed, published, and registered by June 2018 were analyzed, and a technical classification system and classification criteria were prepared through expert discussion. To use fuel cells as an external power source to prevent the corrosion of natural gas large-scale pipelines, it is believed that rights can be claimed using an energy control system and methods having 1) branch structures of pipeline and facility designs (decompressor/compressor/heat exchanger) and 2) decompression/preheating and pressurization/cooling technology of high pressure natural gas.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.218.1-218.1
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• 2010

천연가스를 대체하며 21세기 신 에너지원으로 기대되고 있는 메탄 하이드레이트가 주목을 받게된 것은 1930년대 시베리아의 화학 플랜트에서 고압의 천연가스 수송용 파이프라인이 막히는 사고가 빈번하게 발생하여 그 원인을 조사한 결과, 파이프 내에서 가스와 물이 결합하여 하이드레이트를 형성하고, 그것이 파이프의 내벽에 부착되어 파이프를 막고 있다는 것으로 밝혀지면서 천연가스 하이드레이트가 주목을 받게 되었다. 또한 메탄 하이드레이트의 경우 46개의 물분자에 8개의 메탄가스 분자가 포획된 구조로, 그 분자식은 $CH_4{\cdot}5.75H_2O$이다. 따라서 메탄가스와 물의 이론적 용량비가 216:1로써, 표준상태에서 $1m^3$의 메탄 하이드레이트는 $172m^3$의 메탄가스와 $0.8m^3$의 물로 분해된다. 만약 이와 같은 특징을 역으로 이용할 경우 메탄을 주성분으로 하는 천연가스를 물에 포집시켜 인공적으로 하이드레이트를 제조할 수 있기 때문에 천연가스 수송 및 저장의 수단으로써 그 중요성이 커지고 있으며, 액화수송보다 18-24%의 비용절감이 이루어진다고 보고하였다. 그러나 인공적으로 메탄 하이드레이트를 제조할 경우 가스 포집율의 예측이 매우 어려운 것으로 알려져 있다. 따라서 본 연구에서는 동일한 조건에서 메탄 하이드레이트 형성의 반복성 실험을 10회 수행한 결과 과냉도가 클수록 최대최소차이가 줄었고 또한 교반을 시킬 경우도 최대최소차이가 줄어 들었다.

• 한국가스학회:학술대회논문집
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• 1997.09a
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• pp.266-273
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• 1997

• THE INDUSTRY AND TECHNOLOGY OF GAS
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• v.2 no.1
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• pp.95-100
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• 1998

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.8 no.1
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• pp.81-86
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• 1996

Subsea pipelines have an important role in the overall tasks of offshore oil and gas production but arc exposed to various hazards with high potential risks of damage resulting in serious economic loss and impact on ocean environment. In this paper, the dynamic free span is analysed, which is one of main risk factors against the safety of subsea pipelines and the allowable length of dynamic free span which is important for the design of subsea pipelines is determined. The allowable free span length is examined by considering the relationship between vortex shedding frequency and natural frequency of pipeline free span, and the variation of the allowable length is analysed for different boundary conditions of pipe ends. The free span is regarded as a beam on elastic foundations and the boundary condition of the beam is generalized by modelling as restrained by linear and rotational spring at each end. A non-dimensionalized curve is obtained to facilitate the determination of exact allowable length of dynamic free span for subsea pipelines and is applied to the pipelines which is to be installed in the gas fields of the south of East Sea of Korea.

• Journal of the Korean Institute of Gas
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• v.18 no.2
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• pp.28-34
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• 2014

In the natural gas pressure regulation station, high pressure natural gas is decompressing using pressure regulation valves. Waste pressure occurred in the pressure regulation process can be recovered through adopting turbo expanders. However, in the waste pressure recovery process, Joule Thompson effect causes below $0^{\circ}C$ and this low temperature freezes outside land of pipeline or generates methane hydrate in the pipeline which can block the pipeline. Therefore, turbo expander systems are accompanying with a boiler for preheating natural gas. Molten carbonate fuel cell (MCFC), one of the high temperature fuel cell, can use natural gas as a direct fuel and is also exhausting low emission gas and generating electricity. In this paper, a thermodynamic analysis on the hybrid MCFC-turbo expander system is conducted. The fuel cell system is analyzed for the base load of the hybrid system.

• JOURNAL OF ELECTRICAL WORLD
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• s.264
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• pp.18-26
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• 1998

• Journal of the Korean Institute of Gas
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• v.6 no.1 s.17
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• pp.38-45
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• 2002

Hydrates are solid cryctallines resembling ice in appearance, which are consist of a gas molecule surrounded by a cage of water molecules. Because of containning a large amount of methane, hydrates have been considered as a future energy resource. However, the formation of hydrates in the oil and gas industries has been known as a serious problem for a long time. The formation of hydrate in pipeline is common in seasonally cold or sub-sea environments with low temperatures and high pressures. Especially, hydrate plug formation becomes a real menace to flow assurance in inadequately protected transmission lines. This study was carried out for the purpose of understanding mechanism of hydrate plugging and examining formation conditions of hydrate in high pressure gas pipeline. In this study, we measured hydrate equilibrium conditions under the various flowing conditions with the methane. The results were presented both the plugging tendency and the effect of flowing velocity.

• Journal of the Korean Magnetics Society
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• v.16 no.6
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• pp.305-308
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• 2006

Magnetic flux leakage (MFL) pigs are traditionally used for the detection of gross corrosion on steel pipelines used for the transmission of natural gas. Alternative nondestructive evaluation (NDE) modalities are required for the detection of stress corrosion cracking (SCC) which tends to exist in colonies oriented axially along the length of the pipeline. This paper describes the use of multiphase rotating magnetic fields in the remote region of the probe as a possible SCC detection mechanism. Details of a prototype pig and test rig are given and the challenges associated with the finite element modeling of the device are discussed. Initial experimental results show that this novel NDE modality is sensitive to axially oriented tight cracks.