Total SA (TOT) is operating a cogeneration turbine at a low rate due to a leaky exchanger at its Port Arthur, Texas, refinery, according to a regulatory filing.

The cogeneration turbine, which provides heat and power, "must be reduced to (its) lowest firing rate in order to fix a leaking exchanger," it said in the filing.

The maintenance is expected to last one day starting early Thursday morning. Total said the leak would be "repaired as quickly as possible and NOx steam returned to service."

The nitrogen oxide steam is used as part of the cogeneration process. Total's Port Arthur plant has the capacity to process 232,000 barrels of crude oil a day.

-By Naureen S. Malik, Dow Jones Newswires; 212-416-4210; naureen.malik@dowjones.com