Risk Analysis of LNG Pipe-in-Pipe Options
摘要
A liquefied natural gas (LNG) liquefaction terminal used a comparative risk assessment to evaluate four different pipe-inpipe options for the loading line design to an offshore jetty system. The safety risk posed by the installation was evaluated with a quantitative risk assessment (QRA) procedure. A separate qualitative assessment was performed to evaluate the security risks associated with the project. Evaluation of the pipe-in-pipe and pipe-in-pipe-in-pipe technologies required additional frequency analysis to address the extra protection layers provided by the multi-pipe designs. The risk assessment process for the novel designs provided a more detailed basis for selection between the alternatives.Introduction. Quantitative risk assessment (QRA) is a systematic analysis of the risks posed from hazardous activities or situations. The quantified or calculated results can be used in support of decision making. A liquefied natural gas (LNG) liquefaction terminal used a comparative risk assessment to evaluate four different pipe-in-pipe options for the loading line design to an offshore jetty system. The safety risk posed by the installation was evaluated with the traditional quantitative risk assessment procedure. A qualitative assessment was performed to evaluate the security and economic risks associated with the project.Methodology. The approach used in the study was that of a classical risk assessment (CCPS 1999); a systematic approach to the analysis of what can go wrong in complex industrial systems. The normal conditions of operation of the system are defined and then the following questions asked:What accidental events can occur in the system?How frequently would each event occur?What are the consequences of each event?What are the total risks (frequencies multiplied by consequences) of the system?What is the significance of the calculated risk levels?These questions correspond to the basic components of risk assessment discussed in Figure 1. Once a system h