NSIKO & BONGA SWA
projects
DORIS performed pre-FEED study of stand-alone FPSO developments for Nsiko and Bonga SWA
DORIS conducted a conceptual/pre-FEED level development study of two new oil discoveries in order to 1) establish technical feasibility and help the client establish commercial feasibility and 2) perform pre-FEED level engineering to facilitate the client’s discussions with their joint venture partner.
Options studied included:
- Stand-alone FPSO developments for Nsiko and Bonga Southwest/Aparo
- Long-distance subsea tiebacks from one field to the other
- Dry tree and FPU-based developments for Nsiko
- Co-development versus phased development
Subsequent to the initial study, DORIS was again contracted to conduct a full pre-FEED study of the NSiko subsea system.
This work entailed extensive steady-state and transient flow assurance, flowline mechanical design and insulation specification, and equipment/controls/distribution system analysis and preliminary design.
Services provided by DORIS:
Concept identification / development / feasibility, including:
- Field architecture
- Transient and steady-state flow assurance and operability
- Flowline specification (size and insulation)
- Topsides HYSYS modeling, heat and material balances, equipment sizing
- Topsides equipment layouts on FPSO, FPU, TLP
- Detailed capital cost and schedule estimates for all scenarios
- Capital cost benchmarking

Main characteristics:
- Water Depth: 1200 to 1800m
- Production Facilities: Subsea wells to local & remote FPU’s (purpose build FPSO, or Semi-submersible)
- Oil Production: Up to 200,000 bopd & 300MMscfd
- No. ofWells: Up to 60 subsea wells
- No. of Drill Centers: 15
- Tieback Distance: Up to 10km when local to FPSO & 20 km to remote host