안전 무결도 수준 기반 해양 CCS 프로젝트 CO2 저장 탱크의 안전 계기 시스템 설계

Abstract

In the Offshore CCS project, the CO2 intermediate storage facility is needed to transport the CO2 transported through the CO2 carrier to the subsea pipeline. The CO2 intermediate storage facility has various components. Among the components, since the CO2 storage tank stores a large amount of CO2, when the tank itself is ruptured, overpressure, low pressure, overcharging, etc., it may cause great damage due to a large amount of CO2 leakage. The system, such as CO2 storage tank, essentially should secure the required functional safety and prevent dangerous accidents when the failure of system occur. In this study, therefore, we perform the SIL (Safety Integrity Level)-based SIS (Safety Instrumented System) design procedures proposed in IEC 61508 and IEC 61511 for CO2 storage tank. First of all, the HAZOP (Hazard and Operability study), a risk analysis method for various operation modes, is performed to identify all the risk factors of the system and the required SIS for risk reduction. The LOPA (Layer of Protection), a method to reduce the incidence of high severity parts of accidents, is performed for setting Target SIL of SIS. Since the failure of level transmitter and MOV can lead to accidents through the analysis of HAZOP and LOPA, it is necessary to design additional SIS for risk reduction of CO2 storage tank. Finally, we design the SIS and validate it with the Result SIL calculation to determine whether the desi