Abstract
Floating liquefied natural gas (FLNG) solutions are built from matured oil floating production, storage and offloading (FPSO) technology, primarily to monetize stranded offshore hydrocarbon reserves by locating a floating production system at the offshore reservoir location. The wellhead gas is brought from subsea completion systems and manifolds to the topsides of the FLNG vessel for oil/water/gas separation, where needed, and gas pretreatment and liquefaction.
FLNG solutions are also being considered for exporting nearshore gas reserves or gas from an on-land pipeline network by locating the liquefied natural gas (LNG) production facility near the shore. The larger on-land baseload LNG export production plants require significant capital and take four to five years to be brought online. The FLNG concept provides a faster way to build a small-scale to midscale LNG production facility nearshore in protected waters and/or dockside and provides flexibility for progressive project development and variable LNG sales commitment volumes.
Liquefaction production capacity is generally governed by the size of the reservoir, gas availability and the strategy to export LNG (volume). The quality (composition) of feed gas brought onboard will dictate the complexity and cost of the FLNG facility. Raw gas from the wellhead may contain a large amount of liquids and condensate and heavier hydrocarbons (rich gas), while a pipeline gas from the onshore pipeline network may be very lean. The FLNG facilities for processing and liquefying raw gas could be complex and expensive. Lean gas does not require complex systems. However, in both cases, with a simple single mixed refrigerant (SMR) liquefaction technology, the facility can be cost-efficient, faster to build and easier to operate.
Several innovative, low-cost and game-changing FLNG configurations have been conceived based on the space-efficient and simple-to-operate liquefaction technology – PRICO® SMR – for both offshore and nearshore applications. The simplicity, flexibility and scalability of this process allow a wide range of liquefaction capacities in a unique single- or multiple-train configuration. These configurations include new-built carriers and conversion of existing LNG and bulk carriers.
This paper covers the development of innovative FLNG solutions, including all critical systems and other aspects of the technology and their impacts on the configuration of these solutions, offshore or nearshore.
