During the night of June 27, 2016, the two personnel on duty at PGP – a control board operator and an outside operator – were stopping production of natural gas
During the night of June 27, 2016, the two personnel on duty at PGP – a control board operator and an outside operator – were stopping production of natural gas liquids due to pipeline problems downstream of the facility. Although this was a non-routine activity, the control board operator had experience conducting the procedure. The operators initiated the necessary steps from the control room, when, at 11:22 p.m., a sudden explosion and fire occurred. No abnormal alarms or other indicators warned the two PGP personnel of any problems. Within a minute of the initial explosion, the operators activated the emergency shut down systems at the plant and sheltered in the control room.
Over the course of the incident, the site experienced 13 different ruptures of piping and equipment. The CSB concludes that the first loss of containment most likely originated at a BAHX when it lost core integrity due to accumulated thermal fatigue.
The BAHX of interest was part of A-Train, one of three process lines (A, B, and C) at PGP. The rupture released flammable hydrocarbon into the process area in and around a variety of potential ignition sources. After ignition, emergency systems depressurized the plant and sent much of the process fluids to a flare, but the rupture also caused a portion of A-Train’s contents to continue to feed the fire, which intensified several times over approximately the next 35 minutes as additional piping and equipment failed. Equipment, piping, and vessels in the A-Train process area were extensively damaged .
• EXCHANGER FAILURE DUE TO THERMAL FATIGUE
• SERVICE LIFE DETERMINATION OF BRAZED ALUMINUM HEAT EXCHANGERS
• SOCIAL MEDIA USE IN EMERGENCY RESPONSE
1. The absence of a reliable process to ensure the mechanical integrity of the heat exchanger contributed to the catastrophic failure of the equipment.