Layout Optimization of Process Module on Floating Storage and Re-gasification Unit Using QRA

Abstract

The floating storage regasification unit (FSRU) process has been designed & constructed as modules to achieve the fastest delivery and the easiest installation of an offshore liquefied natural gas (LNG) project. Project efficiencies, including the cost of handling materials, minimization of project delays, and avoidance of bottlenecks require the use of an appropriate module layout in the engineering phase. We present a new framework for the module layout optimization problem in the FSRU process, considering the risk, operation, and maintenance of the process module in a limited area. The developed model aims to minimize the cost of the piping connected between the modules considering both the safety and economy of the process against fire and explosion scenarios. In addition, a quantitative risk assessment (QRA) study was conducted using individual risk indices for determining the risk-avoiding safety distance between the module and the control bridge to evaluate the risk associated with the LNG regasification process. Moreover, a case study was conducted on the conceptual design layout to illustrate the applicability of the proposed model on an FSRU that can process 1,000 million standard cubic feet per day. Overall, the developed model suggested safety guidelines for the operation and maintenance of the optimal module layout in case of fire & explosion accident.