• Journal of the Society of Naval Architects of Korea
• /
• v.49 no.6
• /
• pp.447-460
• /
• 2012

In this study, the shutdown system of the fuel gas supply system is designed based on the Safety Integrity Level of IEC 61508 and IEC 61511. First of all, the individual risk($10^{-4}$/year) and the risk matrix which are the risk acceptance criteria are set up for the qualitative risk assessment such as the HAZOP study. The natural gas leakage at the gas supply pipe is identified as the highest risk among the hazards identified through the HAZOP study and as a safety instrumented function the shutdown function for leakage was defined. SIL 2 and PFD($2.5{\cdot}10^{-3}$) for the shutdown function are determined by the layer of protection analysis(LOPA). The shutdown system(SIS) carrying out the shutdown function(SIF) is verified and designed according to qualitative and quantitative requirements of IEC 61508 and IEC 61511. As a result of SIL verification and SIS conceptual design, the shutdown system is composed of two gas detectors voted 1oo2, one programmable logic solver, and two shutdown valve voted 1oo2.

• Transactions of the Korean hydrogen and new energy society
• /
• v.34 no.3
• /
• pp.297-306
• /
• 2023

The frequency of fatal accidents that can occur at hydrogen refueling station was compared with the risk criterion for the general public suggested by the health and safety executive. If hydrogen refueling station meets the accident prevention facility standards presented in KGS Code FP216/217, it was confirmed that the risk of hydrogen refueling station was not at an unacceptable (intolerable) risk level. However, the risk of hydrogen refueling station due to small leak was analyzed as low as reasonably practicable. Therefore, methods for improving the safety instrumented function of hydrogen refueling station were reviewed. It was confirmed that the risk of hydrogen refueling station can be affected by the number of installed safety instrumentation system components, redundant architecture, mission time, proof test interval, etc. And methods for maintaining the risk of hydrogen refueling station at an acceptable risk level have been proposed.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 1994.05a
• /
• pp.64-77
• /
• 1994

현재 건설중인 3톤/일 규모의 석탄가스화기 운전제어를 위한 콘트롤시스템은 각종 하드웨어와 소프트웨어로 구성된다. 하드웨어는 운전자가 접하게되는 컴퓨터 화면(Operator Console), 운전 제어용 판넬(Hardwired Console), 본 시스템의 핵심인 콘트롤러(PLC; Programmable Logic Controller), 폭발성가스와 분진이 있는 환경하에서의 안전운전을 위한 본질안전 장벽(Intrinsic Safety Barrier) 및 운전정보 수집과 운전 제어를 위한 각종 전/계장품(Field Instrument) 등으로 구성된다. 본 시스템에 포함되는 소프트웨어에는 운전자와 콘트롤러간의 통신을 위한 운전제어화면(GUI;Graphical User Interface), 전체적인 제어를 위한 콘트롤로직(Control Logic)등이있다. 한편 각종 펌프 및 보일러 등 보조설비로의 전기공급을 위한 MCC(Motor Control Center)도 하나의 구성원이 된다. 본 논문은 석탄가스화 반응기의 운전에 관한 전반적인 검토와 콘트롤시스템을 구성하는 각 요소와 각각의 특징 및 그 개발 현황에 대한 검토를 그 내용으로 한다. 본 연구과제를 통해 제작, 설치될 석탄가스화기는 차세대 발전 시스템으로 주목을 받고있는 석탄가스화 복합발전시스템의 핵심부분으로, 본 반응장치의 제어에 관한 경험은 상용 규모의 석탄가스화 반응기에도 유사하게 적용될 것으로 기대된다.

• Journal of the Korean Institute of Gas
• /
• v.21 no.2
• /
• pp.32-40
• /
• 2017

Safety Instrumented Systems (SIS) have wide application area. They are of vital importance at process plants to detect the onset of hazardous events, for instance, a release of some hazardous material, and for mitigating their consequences to humans, material assets, and the environment. The integrated safety systems, where electrical, electronic, and/or programmable electronic (E/E/PE) devices interact with mechanical, pneumatic, and hydraulic systems are governed by international safety standards like IEC 61508. IEC 61508 organises its requirements according to a Safety Life Cycle (SLC). Fulfilling these requirements following the SLC can be complex without the aid of SIS supporting tools. This paper presents simple SIS support tool which can greatly help the user to implement the design phase of the safety lifecycle. This tool is modelled in the form of Android application which can be integrated with a Web-based data reading and modifying system. This tool can reduce the computation time spent on the design phase of the SLC and reduce the possible errors which can arise in the process. In addition, this paper presents an optimization approach to SISs based on cost measures. The multi-objective genetic algorithm has been used for the optimization to search for the best combinations of solutions without enumeration of all the solution space.

• Journal of the Korean Institute of Gas
• /
• v.24 no.4
• /
• pp.32-38
• /
• 2020

Based on the cases of fire and explosion accident in the chemical reactor, thr problems of preventive measures installed in the chemical reactor were analyzed. The chemical reactors produce a variety of chemicals and install rupture disk to relieve the pressure that rises sharply in the event of a runaway reaction. In order to maintain the function of the rupture disk, the emissions was allowed to be discharged into the atmosphere, resulting in fire and explosion accidents. As a way to improve this, safety instrumented system based on the safety integrity level(SIL3) was applied as a preventive measures for chemical reactor. Two emergency shur-off valves are installed in series on pipe dropping raw materials for chemical reactor so that the supply of raw materials can be cut off even if only one of the two emergency shut-off valves is operated during the runaway reaction. The automatic on/off valve is installed in parallel in the supply pipe of the reaction inhibitor so that the reaction inhibitor can be injected even if only one valve is opened at the time of the runaway reaction.