by Steven Randall
Earlier this year, the largest floating object ever built, the Shell owned PRELUDE floating LNG platform (technically not a ship as it does not propel itself), was towed by three large tugs from the Samsung Heavy Industries' Goeje Shipyard in South Korea, to it's operational resting site, 475 km north north east of Broome in Western Australia. While not the first FLNG to be put into operational status, it is certainly the largest oil and gas rig ever built.
A few quick figures about Prelude...
- Approximate cost to the group of US$ 12 Billion, and taking 5 years to complete construction.
- Fully loaded weight of over 600,000 tons - 5 times larger than the USS Enterprise. This weight includes over 200,000 tons of steel.
- Vessel will be 488 meters long, and 75 meters wide.
- It will produce 3.6 million tons of LNG, 1.3 million tons of light oil condensate, and 400,000 tons of LPG a year for over 25 years, and operate on the Prelude and Concierto gas fields.
- Moored in 250 meters of water, approximately 220 km directly off the coast.
- Approximately 140 people will operate this LNG golliath 24 hrs a day all year.
Everything about Prelude is big - even HUGE in size. Many of the items and much of the equipment on Prelude are "..world first.." in terms of their pure size and power. The turret anchor mooring is a good example of the enormous size of things ....
..Weighing over 11,000 tons; 100 meters high and 26 metres in diameter, this monster device is designed to perform three key tasks...Provide a mooring capacity that keeps Prelude in position over the gas fields... Allowing the vessel to able to rotate around a single point to continually receive the raw gas being drawn in. Thirdly, to enable the vessel to be able to stay permanently on station, riding out ANY type of storm weather. This will include the possibility of category 5 cyclones,, with 70 foot waves and winds over over 300 km/ hr.
The mooring system is designed to enable Prelude to receive incoming gas from the undersea wellheads, which are drilled down hundreds of meters into the gas fields.
The turret is connected to the seafloor by 16 chains, each one of which is connected to a steel/ concrete pile 5 meters in diameter, and driven 15 meters into the sea bed. These chains provide the anchoring action, and a ..braking effect.." on the platform as it moves around with the sea conditions.
This vessel and it's self contained production facilities, is one of a long line of LNG production plants that began their journey 5-15 years ago on the road to capitalizing on Australia's huge natural gas resources. The world is hungry for cleaner fuels to produce the ever growing quantities of power for developing nations, and LNG has a key role to play in this space.
For more information about LNG in the Asia Pacific region, go to the display map at https://www.businessmapsaustralia.com.au/collections/australias-energy-collection/products/asia-west-pacific-lng-terminals-large-format