Event
- Event ID
- 194
- Quality
- Description
A release of a mixture of hydrogen, nitrogen and ammonia ignited and exploded in the ammonia synthesis unit. The release was due to a cracked pipe near a flange located at the top of the gas-gas heat exchanger.
The leak immediately ignited, resulting in a powerful explosion followed by a fire, brought under control in less than a hour.
The gas mix consisted in 69% of hydrogen, 23% of nitrogen and 8% of ammonia.- Event Initiating system
- Classification of the physical effects
- Hydrogen Release and Ignition
- Nature of the consequences
- Macro-region
- Europe
- Country
- France
- Date
- Component involved
- pipe (generic)
- Failure mode
- rupture & ignition
- Initiating cause
- unknown
- Root CAUSE analysis
The INITIATING CAUSE was the release of process gas due to a crack on a pipe connected to a heat exchanger.
The ROOT CAUSE is unknown.
- Root causes
- Unknown
- Date entry in HIAD
- 01/01/2021
Facility
- Application
- Chemical industry
- Sub-application
- Fertilisers production
- Hydrogen supply chain stage
- All components affected
flange, pipe, heat exxhanger
- Process temperature range [C]
- High temperature (100°C to 500°C)
- Process pressure range [MPa]
- medium to high pressure (10 to 50 MPa)
- Location type
- Open
- Location
- populated area
- Operational condition
- UNKNOWN
- Description of the facility/unit/process/substances
From the provided data: 30C, 300 bar and %vol., a total mass of 130 kg can be calculated, out of wich 14 kg of H2
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Currency
- Euros
- Property loss (onsite)
- 1.300.000
- Post-event summary
The material damage was assessed between the 3 and the 8 millions of French Francs.
The plant was stopped for 5 weeks.- Emergency action
The operator shut down the compressors and the circulation pumps, and alerted the fire brigade of a neighbouring company. Internal firefighters and external emergency services extinguished the fire within 45 minutes by injecting pressurised nitrogen. After which they focussed on the insulations, which was till burning.
In-depth data
- Release type
- gas mixture
- Involved substances (% vol)
- H2 69%
N2 23%
NH3 8% - Released amount (kg)
- 14
- Release pressure [MPa]
- 30
- Probable IGNITION SOURCE
- Explosion type
References
- Sources categories
- ARIA
- Reference & weblink
Event no 19080 of the French database ARIA
