Azurite Field Development: FDPSO Design And Integration Challenges

Abstract

Abstract This paper addresses the unique design, installation and integration challenges associated with the incorporation of a modified land based drilling rig onto a conventional Floating, Production, Storage and Offloading (FPSO) vessel. The Azurite Floating, Drilling, Production, Storage and Offloading (FDPSO) serves as the specific vehicle for this discussion. The following narrative outlines the Azurite project team's original design philosophy of allocating dedicated space for the drilling facilities, the self-sufficient stand-alone concept with regard to services and utilities, and the " plug ‘n’ play?? approach to hookup and commissioning. This paper also highlights further design development and fabrication and installation activities that impacted the project team's philosophy, and how the Azurite project team adjusted to challenges incurred along the way. Introduction The Azurite field in Mer Profonde Sud (MPS) block offshore Republic of Congo employs an industry-first Floating Drilling Production Storage and Offloading (FDPSO) vessel (ref. Figure 1). Combined drilling and production operations do not represent new technology per se as both SPAR and tension leg platform (TLP) concepts also afford this capability. However, Azurite represents the first time that drilling operations were conducted from an FPSO. A major advantage for this concept was the combination of drilling and production activities with the storage capacity of a FPSO, thus making this a viable - and optimal - alternative to develop a remote field like Azurite. The concept has broad appeal for field developments, as a solution to monetize even marginal fields, or as an early production system in a phased development. Re-thinking the traditional approaches to drilling and facilities to create the industry's first FDPSO meant bringing together two disciplines, with philosophies sometimes at odds with each other, to design an integrated facility that would allow both parties to safely and efficiently operate with as few constraints or conflicts as possible. Challenges associated with Azurite FDPSO were not limited to re-thinking the approach to drilling and the traditional layout of production/utility modules, but also the integration of drilling support and safety systems with those of the production/utilities and marine systems. Integration consisted of the addition of a moon pool and 56 drilling and production equipment and modules, including the installation of the rig derrick. The resulting certification of the production, drilling, and marine systems as part of the overall vessel certification also provided unique issues that required close coordination and resolution with the FDPSO's classification society. This paper will focus on the design and integration challenges encountered during the transformation of a converted very large cargo carrier (VLCC) trading tanker into the Azurite FDPSO. Particular emphasis will be given to the layout of both production and drilling equipment on the deck and around the moon pool, and the associated contracting and logistical challenges.