Fire in a chemical factory

A fire broke out following a hydrogen leak on the Cyclododecane unit in a chemical plant.
A plume of smoke became visible outside the site. The fire was brought under control by putting the unit in safe mode, implementing the internal resources available on site (monitor lance, sprinkler ring and extinguishers), and finally by the intervention of the internal firefighters. The staff was evacuated and the internal crisis unit triggered. The fire was extinguished in 30 minutes.

The post-incident analysis revealed a hole in the connection of the vent manifold, upstream of the evacuation pipe. The failure was caused by external corrosion under the thermal insulation layer. It caused a hydrogen leak and a flow of Cyclododecane. The released hydrogen auto-ignited and the fire spread to the Cyclododecane.

The INITIATING cause was the failure of a connection due to external corrosion. The presence of a thermal insulation layers around the piping did not allow for a visual inspection of the components.
This is a well-known cause for corrosion to proceeded to full component failure, and suggest a ROOT CAUSE related to a inadequate inspection/maintenance procedures and tools.

furnace, exhust pipe

The operator noted only material damage. The water used to extinguish the fire was safely stored.

Following the event, the operator implemented the following actions:
• To repair of all vent collectors and the evacuation pipe;
• To add an alarm on the relative concentrations between raw materials, to detect over-consumption of hydrogen;
• To add an audible and visual alarm locally in the workshop in case of fire;
• To inform of the event all production teams.