(Adds details on work under way, background about refinery,paragraphs 4-9)
HOUSTON, June 13 (Reuters) - A 200,000 barrel per day (bpd)crude distillation unit at Motiva Enterprises' PortArthur, Texas, refinery is expected to return to productionwithin seven to 10 days after completion of unplanned repairs,sources familiar with the refinery'soperations said on Friday.
The largest of three CDUs at the 600,000 bpd Motiva PortArthur refinery is running at slightly reduced rates while workis being done on hydrotreating units, the sources said.
A Motiva representative was not immediately available todiscuss the refinery operations on Friday, but the company saidon Thursday it was performing unplanned work on some of theunits at the refinery.
The 200,000 bpd CDU, called VPS-4, was taken out ofproduction last week for repairs on a heat exchanger on theunit, the sources said. The repairs were expected to last alittle more than two weeks.
The largest of the three crude units at the refinery,325,000 bpd VPS-5, is at slightly reduced production levelswhile hydrotreating units are undergoing repairs andmaintenance.
A third CDU, 80,000 bpd VPS-2, continues in operation whilethe work is under way.
The three CDUs do the initial refining of crude oil cominginto the refinery and provide feedstock to all other productionunits.
Motiva is a 50-50 joint venture between Royal Dutch ShellPlc and Saudi Aramco Oil Co. The Motiva PortArthur refinery is the nation's largest.
Hydrotreaters use hydrogen to remove sulfur from refinedproducts in compliance with U.S. environmental rules. (Reporting by Erwin Seba; Editing by Meredith Mazzilli and TomBrown)
