Technical features

The offshore Terminal is 375 meters long, 115 meters wide and the main deck is 18 meters above the sea level, with the top of the flare tower rising 87 meters above sea level.

The components of the Terminal include:

a) the concrete Gravity Based Structure (GBS) 

b) two LNG storage tanks inside the GBS 

c) the regasification plant 

d) facilities for mooring and unloading LNG vessels 

e) living quarters 

f) a pipeline connected to the mainland

Gravity Based Structure
The main feature of the Adriatic LNG Terminal is its concrete Gravity Based Structure (GBS), a massive construction that rests on the seabed at a depth of about 29 meters. Made of 90,000 cubic meters of cement and 30,000 tons of steel reinforcement, the GBS was built at the Campamento construction site in the Bay of Algeciras in Southern Spain. The GBS is 180 mt. long, 88 mt. wide and 47 mt. high: larger than two soccer fields and as high as a ten-floor building most of which is under water.

LNG storage tanks
Inside the GBS are two LNG storage tanks, each with a capacity of 125,000 cubic meters, made of steel with 9% nickel to provide cold temperature performance. Specially designed using ExxonMobil patented modular technology they were built at one of the world’s largest shipyards, in South Korea. For transport reasons, each tank was designed in 3 modular parts, which were then shipped to the Campamento construction site in Spain. There they were installed in the Terminal’s Gravity Based Structure using custom-designed systems and connected to each other and the regasification plant by special welding techniques. LNG is stored in the tanks at atmospheric pressure and at the temperature of minus 162° C, in order to keep it in its liquid form.

Regasification plant
The Terminal’s regasification plant is located on the top of the GBS. It consists of four LNG Open-Rack vaporizers that operate using the natural heat of sea water, an energy recovery LNG vaporizer that reutilizes heat from the gas turbines, two cryogenic compressors, four pumps used to lift the LNG from the tanks, and five send-out pumps that send the gas through the vaporizers and into the external pipeline. The plant also includes a number of auxiliary facilities, such as gas turbine-powered electricity generators and the electrical control center.

Berthing and unloading facilities
The terminal also includes facilities for mooring and unloading LNG vessels. Key components of the berthing facilities are the “Mooring Dolphins” constructed in the Arsenale shipyard in Venice. These structures are designed to safely accommodate a wide range of different sized LNG carriers. Each Mooring Dolphin structure consists of a base (reinforced concrete base slab, walls and roof slab approximately 7 meters tall), two reinforced concrete columns rising above base (approximately 28 meters tall) and a steel truss deck (63 meters long and 8,5 meters wide) sitting on top of the columns. The structures (9.000 tons each) were towed for 50 kilometers from Venice to the Adriatic Sea, placed on the sea floor on both east and west ends of the GBS and then connected to the terminal by steel walkways. In addition, for offloading LNG carriers the terminal has installed specially designed loading arms that can be connected and operated in a much wider range of sea states consistent with an offshore location. These arms transfer the LNG from the vessel to the pipes that carry it to the terminal storage tanks. The entire system was designed and tested to ensure safe operation during mooring, unloading and departure operations, even in severe weather conditions.

Living Quarters
The operating and maintenance staff on the Adriatic LNG Terminal are on hand 24 hours a day, 7 days a week and therefore every effort has been made to provide them with a comfortable environment for both working and relaxing. The specially designed personnel module, housing up to 60 members of staff, is therefore a self-contained facility that includes living and sleeping quarters and the Terminal’s state-of-the-art Control Room. Here, thanks to highly advanced control communication, video camera and radar systems, operators can monitor every aspect of the Terminal’s operating cycle, from the storage tanks to the metering station, while also maintaining contact with the Shore Base, passing vessels and marine authorities. The Terminal crew’s living quarters, on the other hand, include a fully staffed kitchen, medical facilities, a laundry and heliport, as well as communal areas for enjoying meals or simply relaxing.