(Updates with potential delays on Lima restart)
By Jarrett Renshaw
PHILADELPHIA, Jan 13 (Reuters) - Three of the largest U.S.oil refineries were working to restore operations on Tuesdayafter a series of weekend glitches temporarily knocked out some1 million barrels per day (bpd) of processing capacity in theworse spate of outages in years.
A fourth plant, Husky Energy Inc's 155,000-bpdLima, Ohio, refinery, was not expected back online until the endof the week after an explosion at its 25,000-bpd isocrackerunit, which sources have said was extensively damaged. Peoplefamiliar with the refinery said icy weather may further delaythe restart.
The disruptions, which included three fires on Saturday andone shutdown late last week, affected about one-fifth of therefining capacity in the eastern half of the United States,fueling deeper losses in U.S. crude oil prices, but boostingprompt gasoline and diesel prices in the New York harbor.
The East Coast experienced its coldest stretch of the winterat the time. Cold weather can sometimes complicate operations athigh-pressure refinery units.
Philadelphia Energy Solutions' 335,000-bpd refinery, thelargest on the East Coast, was showing the first signs of arestart at its larger 200,000-bpd crude unit on Tuesday after autility system failure, according a report from Genscape, anindustry information provider. Weak furnace stack activity hasbeen reported from the unit, Genscape said. The crude sectionremained below operational levels, according to Genscape. Theplant was also pressing ahead with maintenance at a handful ofsecondary units due to start in a week's time.
Marathon Petroleum Corp's 212,000-bpd Robinson,Illinois, refinery planned to restart by Tuesday, a source said,after a fire shuttered its crude unit and vacuum distillationunit. The cause of the fire was not known.
Also in Illinois, BP Plc was restarting a90,000-bpd crude unit and a 60,000-bpd reformer at its Whitingplant on Monday after freezing temperatures caused them to shuton Jan. 8, sources said. Restart plans over the weekend werealso delayed by the cold.
The largest crude unit at the refinery, with a 240,000-bpdcapacity, briefly cut back production over the weekend, butreturned to normal service on Monday.
For physical crude oil markets, the outages may add topressure that has been steadily building for months. Theresponse in cash markets was muted on Tuesday as supply remainedabundant and most outages appeared set to be brief. (Additional reporting by Erwin Seba in Houston; Editing byJonathan Leff and Jeffrey Benkoe)
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