Objectives / Scope: This paper will look at the technical, strategic and commercial benefits of Barge Liquefied Natural Gas (BLNG) technology in Deepwater and Onshore gas developments. Methods, Procedures, Process: The majority of the FLNG vessels currently operating are ship-shaped and designed for offshore, over-field locations. However, this approach does not necessarily offer the optimised solution for gas monetisation. Equally where there is an abundant source of onshore gas, onshore liquefaction plants have generally been selected, e.g. US Gulf Coast, this may not be optimum. An alternative solution in both these situations is BLNG, focused on nearshore positioning with liquefaction facilities mounted on a simple floating or grounded substructure with the balance of the systems (pre-processing, liquids handling, possibly storage etc.) decoupled from the liquefaction technology and in a separate location, such as a Central Processing FPSO in the deepwater or a gas processing facility near the development wells onshore. Results, Observations & Conclusions: This paper addresses the following benefits of BLNG and why it's becoming an increasingly viable gas monetisation concept. Technical • Safety in both the operating and construction phases. • This offers a "design one, build many" philosophy enabling a more efficient production line or "factory" approach to fabrication. • A multiple module LNG train configuration enables liquefaction to closely and efficiently match gas production rates. • Nearshore BLNG may be able to achieve a lower carbon footprint by utilising (a degree of) power from shore. Commercial • With multiple small LNG trains the reduction in export capacity during planned/unplanned shutdowns is limited to only the capacity of a single train. • A facility's capacity can easily be increased by additional barges and contractible in late field life, as the field moves off plateau. Strategic • BLNG construction, fabrication and pre-commissioning can be performed in a dedicated yard rather than at a remote site. A controlled environment with an already skilled workforce in place. • Potential for separate FLNG storage can be provided in a separate carrier moored alongside and not in the barge hull. • BLNG is well suited to stranded gas as the barge is more mobile and amenable to relocating elsewhere for a new gas stream. Decommissioning is simplified, and environmental risks are reduced compared to in-situ decommissioning. Finally, the paper will address a more certain approach to the selection of a BLNG solution where the optimum gas monetisation solution is identified in the concept phase front-end loading (FEL 1) of a project. Novel / Additive Information: BLNG allows the disconnection of a deepwater or onshore development from the 'conventional' approaches to liquefaction; it offers an alternative to both deepwater FLNG and onshore liquefaction potentially allowing further optimisation in the construction, operations and overall economics of LNG developments.
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