NEW YORK - Valero Energy Corp on Saturday reported an upset at a sulfur recovery unit at its 325,000 barrel-per-day refinery in Port Arthur, Texas.

The upset was caused by a heater tripping offline, the company said in a filing with the Texas Commission for Environmental Quality, but did not specify if the incident had any impact on operations.

A company spokesman was not immediately available to comment. (Reporting by Rebekah Kebede; Editing by John Picinich)