Fire in a Process Reactor of a Metallurgical Plant
A fire in a metallurgical plant (classified Seveso)The fire initiated in a acid treatment reactor of a workshop handling cementation of indium . Under normal conditions, the reaction of the process in the tank releases hydrogen. The fire propagated to the plastic components above the tank, causing black smoke released inside the workshop. The origin of the fire were sparks produced by the grinding of metal gratings overhanging the tank. According to the ARIA report (see references), they must have come into contact with the gaseous atmosphere of the tank through the throughput of the stirring shaft. The grinding work had been allowed by an intervention permit and was equipped with protections designed to limit the dispersion of sparks.
Event Date
January 16, 2015
Record Quality Indicator
Region / Country
Event Initiating System
Classification of the Physical Effects
Nature of the Consequences
Causes
Cause Comments
Immediate cause were the sparks generated by grinding, supposed to enter the tank containing hydrogen as reaction product. The root cause is unknown, but it could be related to the use of inadequate measures for avoiding ignition sources inside the tank during maintenance works.
Facility Information
Application Type
Application
Specific Application Supply Chain Stage
Components Involved
acid metallurgical treatment reactor
Storage/Process Medium
Location Type
Location description
Industrial Area
Pre-event Summary
Maintenance works were executed on top of the reactor tank
Lessons Learned
Lessons Learned
The fact that the inspection required for the future the systematic implementation of thermal camera during firefighting is due to the fact that during the emergency actions, the fire regained strength due to undetected hot spots. The ARIA report (see references) does not raw any lesson learned. Nevertheless, it may be reasonably assumed that the event would profit from improved maintenance procedure, such as inertization of the tank and monitoring hydrogen concentrations in the gaseous phase of tank.
Event Nature
Emergency Action
The second responders extinguished the fire after 15 minutes using foamers and cooled the installations. The fire resumed after a few minutes, as some undetected hot spots had remained. The further use of foamers allowed its final extinguishment.
Detonation
No
Deflagration
No
High Pressure Explosion
No
High Voltage Explosion
No
Source Category
References
References
Event description in the French database ARIA
https://www.aria.developpement-durable.gouv.fr/accident/46155/
(accessed September 2020)