(Adds details on overhaul, background on refinery)
HOUSTON, Feb 22 (Reuters) - The second largest crudedistillation unit at Motiva Enterprises 603,000barrel per day (bpd) Port Arthur, Texas, refinery was nearing areturn to production on Monday for the first time since amulti-unit overhaul began in late December, sources familiarwith plant operations said.
The 195,000 bpd CDU, called VPS-4, returned to operatingtemperatures over the weekend and was circulating crude oil, buthad not resumed production on Monday morning, the sources said.
A Motiva spokesman was not immediately available to discussoperations at the Port Arthur refinery.
VPS-4 was scheduled to return to operation a week ago andMotiva is anxious to restart production as supplies of crude maystart backing up if production does not resume, according to thesources.
A 49,000 bpd catalytic reformer has been on warm circulationat the refinery since last week, awaiting the return of VPS-4,which like all CDUs does the intial refining of crude oil cominginto a refinery and provides feedstock for all production units.The reformer converts refining by-products into gasolinecomponents.
A 54,000 bpd coker was also shut as part of the overhaul.
Motiva is a joint venture between Royal Dutch Shell Plc and Saudi Aramco. The Port Arthur refineryis the nation's largest. (Reporting by Erwin Seba)
