World's Largest Offshore Facility Developing Rapidly

Shell's Prelude FLNG will be the largest floating offshore facility in the world; the project has moved forward at a rapid pace.

Published Sep 25, 2013 11:41 AM by The Maritime Executive

Drydocks World will be delivering the pioneering Prelude FLNG Turret Modules to Shell very soon. The first Module, the bogie support structure - standing 22 meters high, with a diameter of 30 meters and weighing 1,300 tons - will be transported to Korea to integrate with the Prelude FLNG vessel. Other modules will soon follow.

The Prelude FLNG unit will be 488-meters long and when fully loaded will weigh more than 600,000 tons. It will be the largest structure ever sent to sea, displacing as much water as a fleet of six aircraft carriers. The vessel is to work at the Prelude offshore field 200 kilometers from the Australian coast.

The turret for Prelude FLNG is the biggest turret ever built and over 800 workers are engaged in its construction. The turret is being built in five modules which when put together will weigh in at 10,500 tons. The first steel cutting took place on May 5, 2012. The nearly 100-meter mooring turret is a vital element of the vessel and along with four groups of mooring chains and suction pile anchors will constitute the largest system in the world and help the vessel to remain stable in high velocity tropical cyclone territory.

His Excellency Khamis Juma Buamim, Chairman of Drydocks World and Maritime World said, “We are extremely excited to be part of a new era in offshore gas liquefaction which will lead the way for many new and challenging projects in the years to come. The turret is essentially the heart of the mooring system and is an engineering challenge which needed to be executed with great technical precision.”

Prelude FLNG Fun Facts

Once operational, the Prelude FLNG facility will produce at least 5.3 million tons per annum (mtpa) of liquids: 3.6 mtpa of LNG, 1.3 mtpa of condensate (equivalent to 35,000 bbl/d) and 0.4 mtpa of LPG.

The floating facility will chill natural gas produced at the field to –162°C (-260°F), shrinking its volume by 600 times so it can be shipped to customers in other parts of the world. Ocean-going carriers will load the LNG as well as other liquid by-products (condensate and LPG) for delivery to market.

The Prelude FLNG facility is being built at Samsung Heavy Industries’ Geoje Island ship yards in South Korea. The Prelude FLNG facility has been designed to withstand the most powerful tropical cyclones. It will remain permanently moored at the location for around 20-25 years before needing to dock for inspection and overhaul.

The Prelude FLNG Project is well placed to help meet the growing natural gas demand of Asia.

Developing the gas at the location of the gas field will reduce impact on sensitive coastal habitats as FLNG avoids the need for shoreline pipe crossings, dredging and jetty works. Product carriers will be far from coastal reefs or whale migration routes.