Development of the Adriatic LNG Terminal Deep Casting Basin Construction Site

Abstract

Summary The world's first bottom-founded offshore liquefied natural gas (LNG) storage and regasification terminal is under development by affiliates of Qatar Terminal Limited, ExxonMobil, and Edison for installation in the Northern Adriatic, 15 km east of Porto Levante, Italy. This paper will describe the unique challenges faced and effort undertaken to locate and transform a casting basin to a world-class construction and integration site, including removal of the earthen wall prior to tow-out of the terminal. The concrete gravity-based structure (GBS) terminal enclosing two 125,000-m3 LNG tanks and supporting 8 GSCM regasification facilities will measure 180 m by 88 m and be located in 29 m of water. These dimensions, as well as proximity to Porto Levante, led to selection of the casting basin in the Spanish Bay of Algeciras as the construction and integration site. The site is under development by the Algeciras Port Authority for use as a container port, and therefore did not have the infrastructure needed to build the terminal. This paper will provide the basis for how parameters such as size, depth, layout, water and electricity supply, accessibility, dredging requirements, lease requirements, availability of workforce, and capacity for growth were established to result in an effective construction and integration site. Some of the execution technologies used for this terminal, such as removal of the earthen wall, installation of regasification facilities, and installation of the LNG tanks will also be described. The conclusions drawn in this paper can be utilized for upgrading of an existing construction site, or development of a Greenfield site into an effective facility for future GBSs, floating structures, or large-scale construction and integration projects.