Freeport LNG pointed to deficiencies in safety valve testing and operating procedures as the root causes of a pipeline explosion that shut its export plant in Texas on June 8, according to a report released on Tuesday.
The fiery explosion at the Texas Gulf Coast plant, the second-largest in the U.S., caused global liquefied natural gas (LNG) prices to spike amid falling Russian supplies to Europe and other outages. The report did not indicate when the plant, which supplies 20% of U.S. LNG exports, would restart.
Freeport said the explosion was directly caused by the isolation of super-chilled LNG in a pipe segment without proper overpressure protection, which then warmed in the outside air. That caused the LNG to boil inside the pipe and the resulting vapor expanded rapidly which led to the explosion and rupturing of the pipeline.
The root causes of the incident were deficiencies in pressure safety valve testing procedures, failure to repurpose temperature alarms used to commission LNG piping that could warn operators of rising temperatures during operations and operating procedures that allowed "operator discretion" to close valves that might cause LNG to be isolated in pipes, the report said.
Freeport said it has adopted procedural changes to avoid operating scenarios that could allow blocked-in LNG in piping segments
It has also enhanced its pressure safety valve testing processes and revised its control systems to alert operators about valve positions or temperature readings that indicate possible isolation of LNG in any piping segments.
In August, Freeport LNG announced plans to restart partial gas-processing at the plant by early to mid-November and aimed to reach full capacity by March 2023.
The company needs full approvals from U.S. regulators before a planned restart can begin. However, regulators have only approved parts of Freeport's proposed changes.
Freeport LNG processes about 2 billion cubic feet per day of natural gas and exports up to 15 million tonnes of LNG per year.
(Reuters - Reporting by Swati Verma and Ruhi Soni; Editing by Mark Potter and Christian Schmollinger)