A major recent development in the LNG industry is the move to offshore operations, initially with FSRUs and now with FLNGs, combined with the corresponding harsh environment. GTT’s membrane technologies have gathered experience in LNG offshore operations since the year 2000 and have become the logical choice for this segment.
Its sustained R&D investments led GTT to develop new applications for the offshore LNG segment, particularly for floating LNG production, storage and unloading facilities (LNG FPSOs) and floating LNG storage and regasification units (FSRUs). GTT’s technology has major competitive advantages on cost, the possibility to optimise storage volumes and, in the case of FLNGs, space per unit of liquefaction. GTT’s systems have become the benchmark for this segment of the LNG offshore industry.
Membrane units provide a flat deck space for easy topside arrangement and a full occupation of the cargo hold, providing compactness and optimization of the hull design.
The tank arrangement is selected either as a one-row arrangement or a two-row arrangement. Membrane solutions have been already validated for several barge designs and site conditions all over the world.
Adaptations to the pump tower have been made to implement retractable pumps for pump maintenance without tank decommissioning.
One or several tanks can be temporarily decommissioned for maintenance purposes while other tanks can be kept in normal operation.
Piping has been adapted for simultaneous operations (production, ship-to-ship transfer, maintenance).
Membrane systems are quicker to cool-down and warm-up.
Formal Safety Assessment and Maintenance Analysis (FSAMA), Failure Mode Identification and Risk Ranking (FMI & RR) were performed to demonstrate the suitability of membrane systems for offshore applications. These analyses have received a Statement of Endorsement from Class.
- Control of both membranes is performed while the tanks are in service to avoid any downtime of the tank,
- Standard and easy procedures in case of repair are applicable offshore
- Access can be provided to any part of the tank if required. Owner & Operator receive the support of GTT Operations Department during operations and maintenance phases.
GTT has developed a hydraulic arm (TIBIA) which can be introduced into the tank through the gas dome to facilitate access to all areas of the tank for inspection and eventual repair, thereby minimizing the requirement for the installation of scaffolding.
Reliability of membrane systems is proven based on the long track record and diversity in terms of application and size of membrane LNGC vessels. Systems and procedures have been refined and enhanced throughout the years, without compromising the safety of the vessels.
The principle of membrane systems guarantees by design that the tank construction schedule is not on the critical path. The large network of experienced yards as well as approved suppliers are all limiting the industrial risk, while bringing cost and schedule advantages to offshore units fitted with membrane systems.
- Opérations de transfert côte à côte validées pour plusieurs zones offshore
- Système de confinement renforcé pour les applications tandem. Opérabilité validée pour des vagues de 5 m de haut