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HOUSTON, March 20 (Reuters) - The largest crude distillationunit (CDU) at Motiva Enterprises' 600,000-barrel-per-day Port Arthur, Texas, refinery has beenroutinely running at or near 300,000 bpd since early this year,sources familiar with operations at the refinery said onThursday.
The 325,000-bpd-capacity CDU called VPS-5 is the centerpieceof a $10 billion expansion completed in 2012 that made therefinery the largest in the United States.
A Motiva spokeswoman declined to discuss the status ofVPS-5.
The CDU has had a troubled history, including a shutdown ofnearly eight months from May 2012 to January 2013 to repairextensive piping damage from a chemical leak. The unit beganoperation in April 2012.
"It's running at 300,000 or a little over," one source said.
After resuming production in January 2013, VPS-5 ran brieflyat full capacity before production was cut by as much as 75,000bpd below full capacity due to vibrations on a 16-inch pipefeeding crude oil into the unit, sources have said.
The vibration problem was thought to be correctable onlythrough replacing the pipe while the unit was shut. A shutdownfor an overhaul will likely be required to take the CDU up to325,000 bpd, according to the sources.
Before VPS-5 began production, it was expected the unit'scrude oil intake could be improved by de-bottlenecking, therefining industry term for improving efficiency, according tothe sources. That process was expected to boost the CDU'sproduction to as high as 370,000 bpd. The increases would not bepossible without the overhaul.
In mid-2013, Motiva planned to shut the unit for up to threemonths to replace the feed pipe, sources have said. But thecompany has put off major planned overhauls at the refineryuntil 2015.
Motiva is a joint venture between Royal Dutch Shell Plc and Saudi Aramco. (Reporting by Erwin Seba; Editing by Jeffrey Benkoe)
