NOVEL OFFSHORE LNG SOLUTIONS

Abstract

The demand to process associated and stranded gas is growing and there is increasing commercial interest in offshore LNG production. Limitations in available land and carrier access, safety and environmental considerations and difficult onshore permitting have created an interest in locating LNG terminals offshore. These factors are providing incentives to develop solutions and the technologies required to transfer the liquefaction and re-gasification segments of the LNG chain to offshore locations. Some of the hurdles that need to be overcome are associated with equipment size, weight and layout, energy consumption, the marine environment and, for floating facilities, the moving environment. All of these aspects need to be addressed to produce an overall design that meets technical, commercial, safety and environmental requirements. This paper presents some recent developments in offshore LNG solutions for floating and fixed offshore LNG production and offshore LNG re-gasification terminals. Specific case studies for each facility are: a floating LNG production facility for the Nnwa-Doro gas field offshore Nigeria; a fixed offshore liquefaction facility in the Arctic region; and, the Adriatic LNG receiving terminal located offshore Italy. Information about an alternative method of transporting natural gas—called heavy liquefied gas (HLG)—which has some specific advantages over traditional LNG, is also presented. For each case study, design, construction, cost and schedule are discussed where applicable.