By Kristen Hays
HOUSTON (Reuters) - Three contractors were hurt in a flash fire late on Tuesday at BP's 337,000 barrels-per-day refinery in Whiting, Indiana, but sources said other refinery operations at the largest Midwest refinery were not affected.
The injured contractors were working on a hydrotreater, one of several units undergoing planned work, when the fire ignited, according to individuals familiar with the refinery operations.
Industry intelligence group IIR Energy said the work on the 105,000 bpd hydrotreater was temporarily suspended after the fire, but is still expected to wrap up by late September or early October.
BP declined comment on the work but said the three injured contractors were in stable condition at a hospital.
One sustained smoke inhalation and the other two suffered burns, BP spokesman Scott Dean said.
BP's on site response crews handled the fire without outside help, the Whiting Fire Department said.
The Chicago cash gasoline and diesel markets shrugged off news of the fire since the hydrotreater was already shut for work. Traders said a half-cent bump in CBOB gasoline differentials stemmed from Wednesday's cycle change, and diesel slipped by a penny per gallon.
The refinery's coker was damaged by fire last month and began restarting last week. IIR Energy said the coker would operate at half capacity until mid to late September while the company repairs the damaged coker drum.
IIR also said the planned maintenance began last weekend on an isomerization unit in addition to the hydrotreater and more maintenance was slated to begin Thursday on a 75,000 bpd sour crude unit.
A major three-month overhaul of a 260,000 bpd crude unit, the largest of the three at the plant, was slated to start in November, IIR said.
That overhaul is part of the refinery's $4 billion upgrade project to increase its ability to process cut-price heavy Canadian crude. The project was slated to wrap up in the second half of 2013.
(Additional reporting by Selam Gebrekidan in New York; Editing by Alden Bentley, Chris Baltimore and Marguerita Choy)