Anticipating future developments and a production increase in the Congo, Perenco has converted an oil vessel into a floating production storage and offloading unit (FPSO). La Noumbi will replace the Conkouati currently in operation on the Yombo field. This conversion perfectly illustrates the know-how and the ingenuity of Perenco’s teams.
Making the choice of a conversion
When the Production Sharing Contract (CPP) in Congo was renewed, Perenco committed to install a new floating terminal on the Yombo field to replace the Conkouati (a facility acquired in 2002 and in place since 1992).
At the launch of the project at the end of 2013, Perenco first contemplated the construction of a new floating production storage and offloading unit. But following the crisis that affected the entire sector, the group re-oriented the project on a much more rational conversion in terms of costs and planning.
A technical challenge and a human experience
The project started in 2014. It was essential to take enough time to carefully define the needs of the subsidiary in the short, medium and long term, seizing the best opportunity and selecting the right partners and a suitable team.
The upstream phase, conceptual studies and definition of the specifications lasted two years. Then, in 2016 the detailed in-depth study and preparation phase for the execution could start. The project team was initially based in Paris before being involved in Singapore from mid-2017.
The Work in Singapore lasted just over a year in a partner shipyard that Perenco had already used to complete four prior conversions.
The finalinstallation phase in Congo off Pointe-Noire coast was scheduled for the last 2018 quarter. La Noumbi transitted on its own.
Innovative and bold technical choices
For this conversion, given the expected volumes to be processed, Perenco chose to use two existing storage tanks on the ship to improve fluid separation efficiency and to considerably reduce the quantity of process equipment to be installed on the deck. This new technical solution required numerous studies to validate fluid diffusion, fluid behaviour and also to define fluid regulation and transfer. The new facilities provides large savings while offering an effective and scalable system.
The FPSO offers many competitive advantages. Maintenance costs for the old building had become disproportionate when compared to expected profits, while production treatment facilities were no longer in line with the needs of the Congolese subsidiary. Yombo generates more and more water so it was crucial to review fluid separation capacities and cope with future water increase. The new FPSO also allowed Perenco to start producing on the adjacent Masseko field.
Last but not least, new living quarters will offer a better working environment and significantly increase accommodation capacity. The 90 staff members working on site who currently operate the field settled in their new quarters from November 2018.
La Noumbi in figures
• Installation date: 31 October 2018
• Design life (or Estimated life span); 20 years
• Main dimensions: L=225m x W=44m
• Storage capacity: 750,000 barrels
• Installed Electrical Supply; 23.2 MW
• Treatment capacity: 12,000 oil barrels per day
• Treatment capacity: 120,000 barrels of water per day
• Accommodation capacity: 140 people