(Adds company comment)
HOUSTON, Sept 28 (Reuters) - No injuries were reported froma Sept. 18 explosion during repairs to the fire-damaged heavyoil hydrocracking unit at Motiva Enterprises' 235,000barrel per day (bpd) Convent, Louisiana refinery, sourcesfamiliar with plant operations said on Monday.
Workers were steaming out the drum on the idled 45,000 bpdhydrocracker, called the H-Oil Unit, said the sources, whorequested anonymity because they were not authorized to discussthe matter with the media.
Outlets on the drum were left open but one or some of thembecame clogged causing steam pressure to build up in the vessel,which ruptured along a seam in the explosion, they added.
"The Motiva Convent refinery experienced a steamoverpressure event on Sept. 18, 2016," Motiva said in an emailedstatement. "There were no injuries or impacts to the environmentor plant operations."
The company did not identify the unit involved.
The H-Oil Unit was shut by an Aug. 11 fire that heavilydamaged the two production streams, called trains, on thehydrocracker. Repairs to one production train are expected to becompleted the end of the year, restoring about half the unit'scapacity to production.
Repairs to the second production train are expected to takeat most a year to complete, sources told Reuters on Monday.
Steaming of the drum is a rarely performed procedure on theH-Oil Unit, the sources said.
Damage from the Sept. 18 steam explosion is expected to adda week to the repairs needed to return the unit to partialproduction by year end, the sources said.
The Convent refinery along with Motiva's refinery in Norco,Louisiana are to become part of Shell Oil Co, the U.S. arm ofRoyal Dutch Shell Plc on April 1, Motiva has said.
Motiva's co-owners, Shell and Saudi Aramco