Event
- Event ID
- 781
- Quality
- Description
At a rubber factory, an explosion occurred inside a lubricant container filled with 18 tonnes of tri-(nonylphenyl) phosphate (TNPP or TNPA).
This tank was stirred and maintained at 45°C. However, the heating circuit routed to the container had broken down 7 days earlier.
With the polluted TNPP scheduled for disposal, the accident occurred during a sawing operation to remove the walkway interfering with the manhole opening.
The TNPP substance underwent hydrolysis in contact with water leaking via the broken coil; the resultant phosphoric acid corroding the steel on the container caused hydrogen to form. The relatively slow hydrolysis reaction was no doubt catalysed by metal particles (rust, etc.).A technician was seriously injured due to a fall.
- Event Initiating system
- Classification of the physical effects
- Hydrogen Release and Ignition
- Nature of the consequences
- Macro-region
- Europe
- Country
- France
- Date
- Component involved
- chemical storage tank
- Failure mode
- internal explosion
- Initiating cause
- accidental hydrogen formation
- Root CAUSE analysis
INITIATING cause: the release of TNPP substance which underwent hydrolysis in contact with water leaking via the broken coil with consequent formation of hydrogen. Ignition very probably was catalysed by metal particles (rust, etc.).
- Root causes
- Date entry in HIAD
- 01/01/2020
Facility
- Application
- Chemical industry
- Sub-application
- rubbers production
- Hydrogen supply chain stage
- All components affected
a lubricant container filled with tri-(nonylphenyl) phosphite (TNPP or TNPA)
- Process temperature range [C]
- ambient temperature (-50°C to +50°C)
- Location type
- Confined
- Location
- industrial area
- Operational condition
- Pre-event occurrences
This tank was typically stirred and maintained at 45°C; however, the heating circuit routed to the container had broken down 7 days earlier.
The accident occurred during a sawing operation to remove the walkway interfering with the manhole opening. The sawing operation was aiming at disposing polluted TNPP.
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 1
- Post-event summary
A technician was seriously injured due to a fall.
- Emergency evaluation
A heating belt (with Tmax < T° of TNPP degradation) replaced the coil, and a posted instruction reminded workers of the product's sensitivity to water.
In-depth data
- Release type
- Gas-liquid mixture
- Involved substances (% vol)
- H2,
H3PO4,
tri-(nonylphenyl) phosphate - Release temperature [°C]
- 20
- Probable IGNITION SOURCE
- Explosion type
References
- Sources categories
- ARIA
- Reference & weblink
ARIA data base
event no. 16467
