ABS Approves First Cylindrical FLNG Design
American Bureau of Shipping has granted approval in principle (AIP) for the Sevan cylindrical floating LNG (FLNG) production unit concept for offshore production, storage and transfer of LNG, LPG and condensate.
The next generation FLNG design concept is based on the circular and geostationary Sevan FPSO design, which is being used in the Norwegian and Central U.K. North Sea and offshore Brazil, and is under construction as the first application of an FPSO unit to be installed in the Barents Sea.
The full scope of design review for the FLNG concept includes an assessment of the feasibility of the structural strength of the equipped FLNG hull and process topside structure as well as a global performance and safety analysis conducted in accordance with the ABS Rules and Guides for floating LNG units.
“By awarding Sevan AIP, we have acknowledged that the company’s innovative approach to designing and constructing a first-of-its-kind FLNG production unit is based on sound engineering practices and ABS classification standards,” said Tor-Ivar Guttulsrød, Director of FLNG, Global Gas Solutions, at ABS. “ABS continues to support new FLNG concepts that, when fully developed and implemented, will strengthen the emerging FLNG market.”
The Sevan FLNG production unit will have a proprietary cylindrical hull capable of operating in more than 3,000 m (10,000 ft) water depth and in harsh environments, such as extreme North Atlantic and cyclonic conditions. The unit design is based on environmental load calculations for a 100-year return storm in the Barents Sea.
The unit can be designed to have gas processing and liquefaction up to 4 MTPA and store up to 240,000 m3 of LNG and 36,000 m3 of condensate.
According to Sevan, some of the most significant advantages of a cylindrical hull design are the elimination of the need for a turret and swivel and the favorable motions with very little roll and pitch, as well as reduction of typical wave induced fatigue loads and minimized hull deflection, which simplifies the topsides design.