A hull longer than the Empire State Building is tall has been floated out of dry dock in Geoje, South Korea. Measuring 488 m (1,601 ft) long and 74 m (243 ft) wide, the hull belongs to Shell's Prelude floating liquefied natural gas (FLNG) facility, which upon completion will be the largest floating facility ever built.

Intended to allow production of natural gas, the processing of it into liquefied natural gas (LNG) and finally the transfer directly to transport ships, all while at sea, the Prelude will weigh more than 600,000 tonnes (661,400 tons) fully loaded and is expected to produce around 3.6 million tonnes (3.9 million tons) of LNG per year. Its total storage capacity is over 430 million liters (114 million US gal), or equivalent to around 175 Olympic swimming pools.

The Prelude FLNG will operate in a remote basin around 475 km (295 miles) northeast of Broome, Western Australia for around 25 years. The area's cyclone season runs from late November to April, but the Prelude is designed to remain onsite all year-round in all weather conditions.

It has been designed to withstand a category 5 cyclone and will be secured in place by one of the largest mooring systems in the world. This consists of a 93-m (305-ft) high turret, (which is large enough to house the Arc de Triomphe) that runs through the Prelude and is anchored to the seabed by four groups of mooring lines.

The mooring system allows the facility to turn slowly in the wind so as to absorb the impact of strong weather while remaining moored over the gas field. Additionally, two of the three 6,700-hp thrusters at the rear of the Prelude are able to operate at the same time to turn the facility out of the wind and allow LNG carriers to pull safely alongside for loading.

The floating behemoth is expected to be completed and producing natural gas by 2017. However, it may soon be overshadowed by something even larger. "We are designing a larger facility," Bruce Steenson, Shell's general manager of integrated gas programmes and innovation told Reuters last week. "That will be the next car off the rails."

The following video gives a brief overview of the Prelude FLNG.

Source: Shell

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