Event
- Event ID
- 967
- Quality
- Description
A diesel and gas leak (H2, H2S, CH4) occurred in a hydrodesulphurisation unit (2,200 t/d). The leak location was on one of the boiler valves of the stabilization column.
The released mixture (390 °C / 35 bar) ignited, and due to the heat developed also other valves started leaking.
The compressor was stopped and the column isolated. The fire was extinguished in 35 minutes.- Event Initiating system
- Classification of the physical effects
- Hydrogen Release and Ignition
- Nature of the consequences
- fire
- Macro-region
- Europe
- Country
- France
- Date
- Component involved
- valve (generic)
- Failure mode
- rupture & ignition
- Initiating cause
- material degradation (thermal stress/cycling)
- Root CAUSE analysis
The ARIA report (see references) mentions that the failed valves were of a special type without flange (?) and that were subject during operation to heavy thermal and mechanical fluctuations, and had already experienced various incidents in the past.
- Root causes
- Date entry in HIAD
- 01/01/2018
Facility
- Application
- Petrochemical industry
- Sub-application
- Hydrodesulphurisation process
- Hydrogen supply chain stage
- All components affected
valve of a boiler. tabilisation unit
- Process temperature range [C]
- High temperature (100°C to 500°C)
- Process pressure range [MPa]
- medium pressure (2 to 10 MPa)
- Location type
- Open
- Location
- industrial area
- Operational condition
- Pre-event occurrences
These boiler valves which failed in this event had already experienced various incidents in the past.
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Emergency action
The fire was extinguished in 35 minutes
Lesson Learnt
- Corrective Measures
The ARIA report (see references) mention as corrective actions (1) the replacement of the failed valve, with another type and (2) improved design to protect them from mechanical and thermal stresses.
In-depth data
- Release type
- Gas-liquid mixture
- Involved substances (% vol)
- H2,
diesel - Release temperature [°C]
- 390
- Probable IGNITION SOURCE
References
- Sources categories
- ARIA
- Reference & weblink
Event description in the French database ARIA
https://www.aria.developpement-durable.gouv.fr/accident/11292/
(accessed October 2020)
