Energy and Exergy Performance of three FPSO Operational Modes

Floating, Production, Storage and Offloading (FPSO) is a floating facility used in primary petroleum processing. In Brazil, most FPSOs have been installed in Campos Basin and new facilities may be implemented in the pre-salt area are projected to boost the Brazilian oil production. Crude oil composition has a significant influence on the operational mode of the FPSO. In this study, three operational modes of a FPSO are assessed: the first mode is used when the crude oil has the maximum water and CO2 contents, the second mode is implemented for a composition of 50% basic sediment and water (BSW) in the crude oil, and the third mode is operated when the crude oil has the maximum oil and gas fractions. The FPSO facility configuration changes with the operational mode, and it is possible to have gas export, gas injection, and CO2 injection, in order to achieve the functional conditions established by the FPSO operator. Energy and exergy criteria have been applied to evaluate and compare the performance of components and systems of the three operational modes of the FPSO. The processing and utilities plants have been modeled and simulated by using Aspen HYSYS®. Results indicate that higher oil content in the crude oil increases the power consumption, the exergy requirement and the destroyed exergy of the FPSO.