Starting Up the Most Powerful ESP Installed into Deepwater Offshore Wells Completed with Open Hole Gravel Packing: A Real Challenge

Atlanta Field, offshore Brazil, is probably the most challenging deep-water heavy oil field in the world. Great challenges have been overcome to build and test the first two wells in this field which have already been detailed elsewhere (Papers OTC 25813, SPE 174893, SPE 174896, SPE 174897, SPE 173946). The refurbishment of the FPSO Petrojarl I, to enable it to process the high viscous oil will be described elsewhere. Finally, the last frontier to prove the technical and economic viability of Atlanta Project is the so called "First Oil" and the ESP operation. In normal conditions starting an offshore well when equipped with an ESP (Electrical Submersible Pump) is not a trivial task. Furthermore, Atlanta's wells lower completion is composed of Open Hole Horizontal Gravel Packs, due to the completely unconsolidated reservoir. To produce the viscous oil to the FPSO, the most powerful ESPs in the world, with 1,550 HP induction motors, were installed into the wells. Because of the low temperature on the seabed (around four degrees Celsius) in the event of any (expected or unexpected) plant or pump shutdowns, the viscosity of the cold oil could increase to up 100.000 cP in a few hours, despite the flowline insulation. Finally, managing the treatment plant start up procedure is a very complex task. All these conditions combined made the Atlanta Field Start Up a real challenge. A very restrictive procedure to increase the production drawdown, the production rates, the ESP demand and the plant processing capacities were successfully implemented. These extremely harsh conditions and the effective procedures to cope with them are thoroughly discussed in this paper.