• 설비공학논문집
• /
• 제22권7호
• /
• pp.442-447
• /
• 2010

FPSO (Floating Production Strorage and Offloading) method for LNG industry is efficient and facile compared to onshore NG (Natural Gas) treatment facility. Five simple natural gas liquefaction cycles for FPSO are presented and simulated in this paper. SMR (Single Mixed Refrigerant) cycle, SNE (Single Nitrogen Expander) cycle, DNE (Double Nitrogen Expander) cycle, PNE (Precooled Nitrogen Expander) cycle, and PDNE (Precooled Double Nitrogen Expander) cycle are compared. Simple analysis results in this paper show that precooling process and adding an expander in the liquefaction cycle is an effective way to increase liquefaction efficiency.

• 한국해양공학회지
• /
• 제32권1호
• /
• pp.51-61
• /
• 2018

In this study, the operability of an FLBT (floating LNG bunkering terminal) was evaluated experimentally. Model tests were conducted in the KRISO (Korea Research Institute of Ships and Ocean Engineering) ocean engineering basin. An FLBT, an LNG carrier, and two LNG bunkering shuttles were moored side by side with mooring ropes and fenders. Two white-noise wave cases, one irregular wave case, and various regular wave cases were generated. The relative local motions between each LNG loading arm and its corresponding manifold in the initial design configuration were calculated from measured 6-DOF motions at the center of gravity of each of the four vessels. Furthermore, the locations of the LNG loading arms and manifolds were varied to minimize the relative local motions.

• Journal of Advanced Research in Ocean Engineering
• /
• 제3권3호
• /
• pp.125-135
• /
• 2017

The paper considers the practical application of the FMEA(Failure Mode and Effect Analysis) method to assess the operational reliability of the LNG(Liquefied Natural Gas) transfer system, which is a potential problem for the connection between the LNG FPSO and LNG carrier. Hazard Identification (HAZID) and Hazard operability (HAZOP) are applied to identify the risks and hazards during the operation of LNG transfer system. The approach is performed for the FMEA to assess the reliability based on the detection of defects typical to LNG transfer system. FTA and FMEA associated with a probabilistic risk database to the operation scenarios are applied to assess the risk. After providing an outline of the safety assessment procedure for the operational problems of system, safety assessment example is presented, providing details on the fault tree of operational accident, safety assessment, and risk measures.

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제6권2호
• /
• pp.307-322
• /
• 2014

With the rate of worldwide LNG demand expected to grow faster than that of gas demand, most major oil companies are currently investing their resources to develop floating LNG-FLNG (i.e. LNG FSRU and LNG FPSO). The global Floating LNG (FLNG) market trend will be reviewed based on demand and supply chain relationships. Typical technical issues associated with FLNG design are categorized in terms of global performance evaluation. Although many proven technologies developed through LNG carrier and oil FPSO projects are available for FLNG design, we are still faced with several technical challenges to clear for successful FLNG projects. In this study, some of the challenges encountered during development of the floating LNG facility (i.e. LNG FPSO and FSRU) will be reviewed together with their investigated solution. At the same time, research of new LNG-related technologies such as combined containment system will be presented.

• Journal of Advanced Marine Engineering and Technology
• /
• 제39권3호
• /
• pp.342-347
• /
• 2015

플로팅 엘엔지선박은 해상에서 LNG 생산 및 천연 가스 공급을 담당하는 새로운 개념으로 부유식 생산설비는 과도한 투자 비용으로 인해 개발 지연중인 한계 가스전에 활력을 주고 있으며, 부유식 공급설비는 육상 LNG 인수기지 인프라가 미비한 지역에 에너지를 경제적이며 효과적으로 공급할 수 있다는 장점을 제공하고 있다. LNG 화물창은 플로팅 엘엔지선박에서 생산 또는 적재된 LNG를 보관하는 주요기능 중 하나이다. 본 연구를 통해 기존 화물창 시스템들의 장점을 결합한 복합 화물창 시스템을 화물창 시스템의 설계 개선방안으로 제안하였고 플로팅 엘엔지선박에의 적용 타당성에 대한 연구를 수행하였다.

• 한국항해항만학회지
• /
• 제45권3호
• /
• pp.87-94
• /
• 2021

국제해사기구의 연료유 황 함유량 제한 등, 세계적으로 강화되고 있는 환경규제로 LNG를 선박 연료로 사용하는 연구 및 사업이 활발히 진행되고 있다. 본 연구에서는 기본설계 되어 있는 부유식 벙커링 터미널(FLBT, Floating LNG bunkering terminal)을 대상으로, STS LNG 하역 작업을 위해 접안 하는 과정을 수치 시뮬레이션으로 평가하였다. 수치해석에서는 예인선이 대상선박을 밀 경우 이를 가상의 펜더로 가정하였으며, 당길 때는 HMPE 로프 특성을 적용하였다. 해석에는 파랑, 조류, 바람 1년 재현 확률의 해상조건을 적용하였다. 수치모델은 선행 모형시험 결과로부터 조정되어 정확한 결과를 얻을 수 있도록 하였다. 해석 결과 LNG선은 대부분의 1년 환경조건에서 안전한 접안이 가능하였다. 파랑 방향에 따라 안정성의 차이가 큼으로 FLBT의 Heading control 기능을 적용하여 횡파를 피한다면 더욱 안정적인 운용이 가능할 것이다.

• Ocean Systems Engineering
• /
• 제2권1호
• /
• pp.49-68
• /
• 2012

In this paper, an offshore process front end engineering design (FEED) method is systematically introduced and reviewed to enable efficient offshore oil and gas production plant engineering. An integrated process engineering environment is also presented for the topside systems of a liquefied natural gas floating production, storage, and offloading (LNG FPSO) unit, based on the concepts and procedures for the process FEED of general offshore production plants. Various activities of the general process FEED scheme are first summarized, and then the offshore process FEED method, which is applicable to all types of offshore oil and gas production plants, is presented. The integrated process engineering environment is presented according to the aforementioned FEED method. Finally, the offshore process FEED method is applied to the topside systems of an LNG FPSO in order to verify the validity and applicability of the FEED method.

• 한국해양공학회지
• /
• 제24권5호
• /
• pp.16-21
• /
• 2010

During the loading/offloading operation of a liquefied natural gas carrier (LNGC) that is moored in a side-by-side configuration with an offshore plant, sloshing that occurs due to the partially filled LNG tank and the interactive effect between the two floating bodies are important factors that affect safety and operability. Therefore, a time-domain software program, called CHARM3D, was developed to consider the interactions between sloshing and the motion of a floating body, as well as the interactions between multiple bodies using the potential-viscous hybrid method. For the simulation of a floating body in the time domain, hydrodynamic coefficients and wave forces were calculated in the frequency domain using the 3D radiation/diffraction panel program based on potential theory. The calculated values were used for the simulation of a floating body in the time domain by convolution integrals. The liquid sloshing in the inner tanks is solved by the 3D-FDM Navier-Stokes solver that includes the consideration of free-surface non-linearity through the SURF scheme. The computed sloshing forces and moments were fed into the time integration of the ship's motion, and the updated motion was, in turn, used as the excitation force for liquid sloshing, which is repeated for the ensuing time steps. For comparison, a sloshing motion coupled analysis program based on linear potential theory in the frequency domain was developed. The computer programs that were developed were applied to the side-by-side offloading operation between the offshore plant and the LNGC. The frequency-domain results reproduced the coupling effects qualitatively, but, in general, the peaks were over-predicted compared to experimental and time-domain results. The interactive effects between the sloshing liquid and the motion of the vessel can be intensified further in the case of multiple floating bodies.

• 산업경영시스템학회지
• /
• 제37권4호
• /
• pp.12-23
• /
• 2014

The O&M (Operation and Maintenance) phase of offshore plants with a long life cycle requires heavy charges and more efforts than the construction phase, and the occurrence of an accident of an offshore plant causes catastrophic damage. So previous studies have focused on the development of advanced maintenance system to avoid unexpected failures. Nowadays due to the emerging ICTs (Information Communication Technologies) and sensor technologies, it is possible to gather the status data of equipment and send health monitoring data to administrator of an offshore plant in a real time way, which leads to having much concern on the condition based maintenance policy. In this study, we have reviewed previous studies associated with CBM (Condition-Based Maintenance) of offshore plants, and introduced an algorithm predicting the next failure time of the compressor which is one of essential mechanical devices in LNG FPSO (Liquefied Natural Gas Floating Production Storage and Offloading vessel). To develop the algorithm, continuous time Markov model is applied based on gathered vibration data.

• Journal of Advanced Marine Engineering and Technology
• /
• 제34권6호
• /
• pp.798-805
• /
• 2010

LNG FPSO 액화 플랜트와 같은 초저온 분야에서 플레이트 핀 열교환기의 국내 연구 실적은 전무한 상태이다. 본 연구에서는 플레이트 핀 열교환기의 독자적 기술을 확보하기 위해 응축 열전달 특성을 이론 및 실험적으로 검증하였다. 시뮬레이션 결과 Plain fin을 제외한 Serrated, Wavy fin은 압력 69bar, 온도 $-140^{\circ}C$에서 응축되었고, 국소열전달계수는 Serrated, Wavy, Plain fin 순으로 높게 나타났다. 실험결과는 정상상태에서 10분간 데이터를 획득하였고 시뮬레이션 데이터값과 12% 미만의 오차범위를 만족하였다.