The Prelude FLNG after the incident last December

The billion-dollar Floating Liquefied Natural Gas (FLNG) facility, Prelude FLNG, is facing “catastrophic failure” caused by a power outage.

Australia’s offshore security regulator has ordered Shell to shut down its Prelude FLNG facility offshore Western Australia, following the fire incident that occurred in December 2021.

Prelude FLNG, has been suspended from operation. The Prelude FLNG facility is undergoing suspension until it was confirmed that the FLNG could operate normally and safely. This is the second time the Prelude FLNG has been forced to shut down since it started production.

The incident last December

Although the fire in early December was not serious, it was successfully extinguished before it spread further without causing any casualties. However, for Shell, it is not easy to resume the production of Prelude FLNG. The fire caused FLNG to lose its main power source and the power supply was unstable, which could lead to a “catastrophic failure” of the hull structure.

The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA)’s investigation report has shown that the steel structure supporting the deck is located in a water-filled cavity at the center of the Prelude FLNG between massive 35-meter-wide insulated storage tanks in minus 162 degrees. Without power, the cavity cannot be heated, preventing the steel temperature from dropping to dangerously low levels.

Australia’s offshore security regulator concluded that unreliable power created a “significantly higher than normal” risk at Prelude FLNG that “if not mitigated, cooling of the substructure adjacent to the LNG storage tank could lead to catastrophic failure”.

Shell has yet to determine the root cause of the initial fire and subsequent electrical and equipment failures, according to the NOPSEMA report. However, NOPSEMA said it was not currently considering prosecution of Shell, which had “appropriately managed” the immediate risk to the crew, and that the incident was under control by the time NOPSEMA investigators arrived.

A Shell spokesman said the company had suspended production of Prelude FLNG and was investigating the root cause of the accident.

The world’s largest FLNG

Prelude FLNG is built by South Korea’s Samsung Heavy Industries (SHI). It is the world’s largest floating offshore plant and floating liquefied natural gas plant. The FLNG was constructed with approximately 260,000 tons of steel and has more than 150 patents. It is capable of producing 3.6 million tonnes of LNG, 1.3 million tonnes of condensate, and 400,000 tonnes of LPG annually. Prelude FLNG is designed to withstand once-in-a-century storms, enough to continue operations during the severe weather conditions of Australia’s tropical cyclone season.

Although the cost has never been announced, the industry speculates that the Prelude FLNG project cost more than 17 billion US dollars (about 113.849 billion yuan), even more than the USS Ford aircraft carrier (about 13 billion US dollars). However, Prelude FLNG has experienced a series of safety and production issues since it set sail from South Korea’s Samsung Heavy Industries to its mooring site off the coast of Australia in mid-2017. In fact, over the past four and a half years, Prelude FLNG has been in normal operation for less than 12 months.

Prelude FLNG shipped its first cargo in June 2019, two years behind schedule. But just over half a year later, Prelude FLNG was shut down in February 2020 due to a power failure. Prelude FLNG resumed production in early 2021 after an 11-month shutdown. Prelude FLNG operated as normal for most of last year until a fire in early December shut it down again.

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Prelude FLNG is located about 475 kilometers north-northeast of Broome, Western Australia. Shell owns 67.5% of the shares, and the remaining shares are owned by Japan International Petroleum Development Co., Ltd. ) and Taiwan PetroChina (5%).

Source eworldship