Floating LNG is Coming of Age

摘要

Global LNG trade is expected to more than double to 725 Mtpa by 2020.Some of the new projects will be developed with floating LNG technologies,perhaps even with a full floating LNG chain:FPSO for LNG production in the field(FLNG), offshore LNG transfer to shuttle tankers,and floating receiving terminal that leads to the eventual gas distribution grid. There are already many floating LNG receiving terminals operating successfully in the world.Now that construction has started on Shell’s Prelude FLNG,a floating LNG project will be realized in 2016.Undoubtedly,more projects will follow. The economics of floating LNG is compelling.Major cost savings can be achieved by eliminating:well head/production platform(s);processing platform that facilitates gas treating,liquids recovery and stabilization;FSO for condensate and NGL; gas compressor and pipeline that transport gas to an onshore LNG plant;with an all-purpose FLNG system located in the field.There are also the intangible cost savings such as efficiency gains by constructing the entire system in a ship yard, material and manpower logistics,and shorter project duration. Many technologies have combined to make FLNG a reality.Reliable subsea well and control systems have mitigated the risks of well operations.Proven glycol(MEG)and other regenerative hydrate management systems have allowed longer tie- back distance.Cost-effective mooring systems for large FPSO,flexible flow-lines and catenary risers have enabled floating systems of FLNG size to be successfully implemented.However,it is the advance of floating LNG technologies that have evolved over the past 25 years that finally tipped the risk-reward equation.Technologies such as offshore ship-to-ship LNG transfer,motion tolerant processing and rotating equipment,LNG spill and gas safety,and deep water cooling water lift systems have matured to an acceptable level. This paper will present the economics drivers that make FLNG chain attractive to producers and buyers alike,and the many conventional production technologies and those unique to FLNG that combined to enable FLNG to be developed with confidence.The realization of floating LNG chain will benefit both producer and consumers alike.