Shell introduces gas onto Prelude FLNG

Shell’s Prelude FLNG facility located offshore Australia has reached what the company says is a significant milestone, with gas introduced onboard. The Gallina, an LNG Carrier from Singapore, carried out the import.

This is a moment of firsts for Prelude, and an opportunity to test processes and systems before the subsea wells are opened at start-up, Shell explained in a statement last Friday.

According to the company, it’s the first time a vessel has berthed side by side with Prelude and tested its offloading arms, in reverse order to how this will work once Prelude is operational. Prelude’s offloading arms have been specifically designed to ensure safe offloading while both the facility and the Gallina are moving. In this case, the offloading arms transferred the LNG from the Gallina to Prelude.

Once onboard, the LNG makes its way through process equipment and pipework and is stored within tanks in the hull of the facility. These tanks have been designed to withstand the ‘sloshing’ of the product that could happen due to the movement of Prelude. Four of the huge LNG tanks, at 39,000 cubic meters each, are now full.

With gas onboard, Prelude’s utilities can now switch to run on gas rather than diesel.

VP Prelude, David Bird, said: “It’s important we take a moment to celebrate and recognize this achievement.

“It’s equally important we don’t lose sight of the end goal – the safe and reliable start-up of our incredible asset, Prelude, and the delivery of gas to our customers.”

Prelude Project Director, Didrik Reymert, stresses the importance of safety now that the facility is ‘live’.

“The risk profile of the facility has changed fundamentally and this has a great impact on how we work,” he said.

“Now, more than ever, we must maintain our unrelenting focus on the safety of our people and our environment.

“Introducing gas onto Prelude is an important step towards start-up but there is a lot of work to do before we get there.”

The next step will be to test and ready the LNG plant on board Prelude in preparation for opening the wells. This is followed by a period called start-up, ramp-up. LNG will be produced after this, when it is safe to do so, Shell concluded.

Built by the Technip-Samsung consortium, the 488-meter-long and 74-meter-wide FLNG unit left the shipyard in South Korea in late June 2017 and reached the Australian waters in late July. It was connected all 16 mooring lines at the Prelude field in August of the same year.

The unit is now located in the Browse Basin, approximately 475km north-north east of Broome in Western Australia.

The largest floating facility ever built will unlock new energy resources offshore and produce approximately 3.6 million tonnes of liquefied natural gas (LNG) per year. It will remain onsite during all weather events, having been designed to withstand a category 5 cyclone. The FLNG will stay at the location for 20 to 25 years.