Fire in a refinery

The event occurred at the in the distillate hydrotreater unit of a refinery. This unit removed sulphur from a hydrocarbon feedstock by hydogenating it with hydrogen. A 12-inch overhead pipe ruptured with a loud noise and released flammable gaseous hydrocarbonsat a temperature high enough to cause spontaneous ignition.
The pipe normally operated at a pressure of approximately 600 pounds per square inch (approximately 40 bar). No personnel were present in the unit when the pipe rupture occurred.
The local fire brigade extinguished the ensuing fire two hours later. No employees or emergency responders were injured. Air monitoring at the perimeter of the refinery did not detect elevated concentrations of any hazardous chemicals.

The fire damage was confined to other equipment in an area of to an approximately 10 square meter. Two fan-type heat exchangers were destroyed by the fire along with an approximately 50-foot section of piping; electrical conduit was also damaged by radiant heat. No blast damage was observed.

The cause of the pipe rupture could not be determined. Nevertheless, the investigation noted there have been a number of past instances of corrosion-related failures in refinery hydrotreater units.

gas recycle line

the investigation reported that there have been a number of past instances of corrosion-related failures in refinery hydrotreater units.

The fire damage was confined to other equipment in an area of to an approximately 10 square meter. Two fan-type heat exchangers were destroyed by the fire along with an approximately 50-foot section of piping; electrical conduit was also damaged by radiant heat. No blast damage was observed.

Air monitoring at the perimeter of the refinery did not detect elevated concentrations of any hazardous chemicals.

A very detailed Emergency Response record is given in the HAZMAT report in the references.

In general, it is important to carefully guarantee the integrity of piping that contains hazardous substances through rigorous inspection and testing, and to adapt them with increasing ageing of the components.