Fire in the Electrical Transformer of a Metallurgical Plant
A fire broke out on a transformer transforming 225,000 V into 15,000 V in a metallurgical plant. This transformer supplies electrical power the site and to a neighbouring factory. In the following three hours, staff brought the fire under control with CO2 extinguishers, the internal emergency plan was activated, and the firefighters ventilated the premises and took readings of the flames using a thermal camera. Meanwhile, however, the shutdown of the electrical installation caused the stop of the operation of an electrolysis unit using zinc sulphate. This unplanned stop of the process caused the generation of hydrogen production a very slow rate: a change from 0 to 8% LEL in 3 hours was detected.For more than an hour, the staff, assisted by a specialized company, was busy in empting 82 tanks of 25 m each with the company's pump truck. After that, the electrical installation was put back into service and all the plant processes were checked.
Event Date
May 27, 2022
Record Quality Indicator
Region / Country
Event Initiating System
Classification of the Physical Effects
Nature of the Consequences
Cause Comments
The presence of a cat in the transformer caused the fire to start. The formation of hydrogen was due to the unplanned stop of the electrolyzer. The root cause can only be guessed, in between design or management shortcoming for not having foreseen the risk of the possibility of sudden stop to zinc production facility.
Facility Information
Application Type
Application
Specific Application Supply Chain Stage
Components Involved
transformator, zinc electrolysis
Storage/Process Medium
Location Type
Location description
Industrial Area
Operational Condition
Pre-event Summary
Hydrogen formation at the zinc electrolyzer was caused by the lack of power supply from the transformer on fire.
Consequences
Number of Injured Persons
8
Number of Fatalities
22
Lessons Learned
Lessons Learned
Unknown
Event Nature
Emergency Action
10:00 - Fire on the transformer transforming Fire under control by means of CO2 extinguishers. The internal emergency plan was activated. The firefighters ventilated the premises and took readings of the flames using a thermal camera. From 12.45 to 14:00, the staff, assisted by a specialized company, worked to eliminate the causes of the hydrogen production from the zinc electrolyzers by empting the supply tanks. 14:15 - Electrical installation put back into service and all the plant processes checked. 14:30 - Firefighters left the site.
Detonation
No
Deflagration
No
High Pressure Explosion
No
High Voltage Explosion
No
Source Category
References
References
ARIA eventhttps://www.aria.developpement-durable.gouv.fr/accident/59092/
(accessed July 2023)