Fire and Explosion at Chemical Plant During Hydrogenation Process
Fire and explosion in a chemicals plantThe process unit affected by the incident was a two-step production, consisting of i) hydrogenation of phenyl acetyl carbinol with benzyl amine in a isopropyl alcohol/water mixture by means of a catalyst ii) removal of the catalyst and further hydrogenation of the solution.At the moment of the incident the operator was starting the first step of the hydrogenation. A first fire, detected by the automatic fire alarm, was followed by a hydrogen leak and explosion, fed by the release of additional chemical agents. One fatality and three first responders were affected by the smoke. According to the investigation described by the ARIA report, the most likely accident scenario was as follows: a) the isopropanol pipe had been fitted with a bypass featuring steel/glass discontinuity with a double enclosure to protect the glass portion of the pipe. Despite the operating procedure notification, the steel side of the valve had never been closed, triggering a 3.5-bar pressure surge on the glass/metal discontinuity each time the pump started. b) Rupture of the glass device caused an isopropanol leak, eventually forming an explosive atmosphere and resulting in an ignition.c) The adjacent hydrogen pipeline, exposed to strong heat failed, and the released hydrogen caused an explosion. d) Moreover, the fire led to a short-circuit, cited as the reason for a malfunctioning phenylacetylcarbinol pump, which in turn helped feed the blaze.
Event Date
July 1, 1997
Record Quality Indicator
Region / Country
Event Initiating System
Classification of the Physical Effects
Nature of the Consequences
Causes
Cause Comments
The immediate cause was the rupture of a pipe with iso-propanol release and ignition and domino effect to the hydrogen line and later to other chemicals.However, various operative and design deficiencies were found during the investigation, so that the root cause is of an organizational nature
Facility Information
Application Type
Application
Specific Application Supply Chain Stage
Components Involved
Low pressure hydrogenation unit in a chemical plant.
Storage/Process Medium
Location Type
Location description
Industrial Area
Operational Condition
Pre-event Summary
At the moment of the incident the operator was starting the first step of the hydrogenation
Currency
Lessons Learned
Lessons Learned
Unknown
Event Nature
Emergency Action
The fire brigade intervened and the fire was contained after 40mn, following the closure of hydrogen and phenylacetylcarbinol feed lines.
Release Type
Release Substance
Detonation
No
Deflagration
No
High Pressure Explosion
No
High Voltage Explosion
No
Flame Type
Source Category
References
References
Full investigation report from the French database ARIA
https://www.aria.developpement-durable.gouv.fr/fiche_detaillee/14700_en…
(accessed September 2020)
Event description inEuropean database eMARS
https://emars.jrc.ec.europa.eu/en/emars/accident/view/5ebb0528-c418-5a8…
(accessed September 2020)