Atteris, in close collaboration with Santos, successfully identified suitable riser configuration options for the Dorado dynamic riser system. Relevant key drivers were also communicated in a timely manner to feed into the FPSO design competition performed in parallel. Preliminary on-bottom stability checks were performed for the flowlines and static umbilical.
The Santos Dorado field is located 150 km north of Port Hedland, Western Australia, within approx. 90 m of water. Development of the Dorado field comprises a floating, production, storage and offloading vessel (FPSO) with a Well Head Platform (WHP) connected via subsea production and injection flowlines, risers and umbilical. The 5 dynamic risers and umbilical connect to the FPSO via an internal Disconnectable Turret Mooring (DTM). Preliminary work was performed during the previous phase based on a tethered wave riser configuration. Santos engaged Atteris to perform a comparative assessment between Lazy Wave, Tethered Wave and Lazy S riser configurations, and provide early indication of the anticipated requirement for secondary stabilisation on the flowlines and static umbilical. Field layout definition and refinement of the WHP platform connection was also required.