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* CDU to be heated to operating temperatures -sources
* CDU to run sweet crude not Canadian crude during start-up (Adds details about start-up process and background,)
By Erwin Seba
HOUSTON, June 12 (Reuters) - BP Plc is preparing tobegin production at the upgraded crude distillation unit at its405,000 barrel-per-day (bpd) Whiting, Indiana, refinery withinseven to 10 days, sources familiar with refinery operations saidon Wednesday.
The CDU, which has been shut since November and is thecenterpiece of a $4-billion revamp of the refinery, is nearingthe end of the cold oil circulation process and workers arepreparing to begin heating the CDU to production temperature ofabout 700 degrees Fahrenheit, the sources said.
A BP representative was not immediately available to discussrefinery operations on Wednesday. The company has said the CDU,called Pipestill 12, is expected to be in operation by the endof the second quarter on June 30.
"They're going to do it real slow," said one of the sources."When you begin heating things up, that's when you are going tofind problems, when things are going to start leaking."
How soon the 260,000 bpd Pipestill 12 actually beginsproduction will depend on what problems are found during theheating process and as the first crude oil is introduced intothe unit, the sources said.
Initially, Pipestill 12 will refine sweet crude oil and notthe cheaper, heavy Canadian crude the refinery is beingoverhauled to process, according to the sources.
Once the overhaul is complete in the second half of thisyear, the Whiting refinery will be able to process 350,000 bpdof crude from Canada's tar sands fields in Alberta. Currentlythe refinery can process 80,000 bpd in Canadian crude.
A crude distillation unit like Pipestill 12 does the initialrefining of crude oil coming into a refinery and providesfeedstock for all other units.
Two other CDUs have remained in operation at the Whitingrefinery while Pipestill 12 has been shut for the overhaul.
The sources said they did not know when Pipestill 12 wouldbegin running Canadian crude.
"They want to make sure there are no problems with itfirst," one of the sources said.
BP has proceeded slowly through start-up preparation ofPipestill 12, delaying the process as problems have developed,sources have said. BP is willing to move slowly with the unit'sreturn to prevent mishaps that could damage the CDU.
Problems with equipment on new or significantly overhauledrefinery units are expected due to the complexity of the unitsthat refine potentially explosive substances at hightemperatures and pressures.
A June 2012 leak of a chemical into a new crude distillationunit at Motiva Enterprises' Port Arthur, Texas,refinery led to 10-month shutdown for repairs.
The Whiting upgrade is part of BP's U.S. refining strategyto focus on plants that have easier access to cheaper Canadiancrude. BP has sold refineries in Texas and California.� (Reporting by Erwin Seba; Editing by Gerald E. McCormick andBob Burgdorfer)
