Event
- Event ID
- 626
- Quality
- Description
A tube in a hydrorefiner heater ruptured resulting in an extensive fire inside and outside the furnace. The main fire in the furnace was extinguished within 15 minutes and the escaping gas / vapour release from the ruptured tubes allowed to burn under controlled conditions. There were no injuries to personnel but the furnace suffered damage estimated at £10,000 (1973).
- Event Initiating system
- Classification of the physical effects
- Hydrogen Release and Ignition
- Nature of the consequences
- fire
- Macro-region
- Europe
- Country
- United Kingdom
- Date
- Component involved
- heat exchanger (pipe)
- Failure mode
- rupture & ignition
- Initiating cause
- over-heating
- Root CAUSE analysis
The investigations revealed that during changes in operating conditions a cold circulation start-up valve was opened by mistake resulting in liquid feed/hydrogen starvation of the heater tubes for a period of 35 minutes and eventual rupture of the tube with massive release of hydrogen and hydrocarbon vapours.
- Root causes
- Date entry in HIAD
- 01/01/2020
Facility
- Application
- Petrochemical industry
- Sub-application
- Hydrodesulphurisation process
- Hydrogen supply chain stage
- All components affected
heater, hydrotreatement furnace
- 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
- Unknown
- Location
- industrial area
- Operational condition
Emergency & Consequences
- Number of fatalities
- 0
- Number of injured persons
- 0
- Currency
- UK£
- Property loss (onsite)
- 10.000
- Post-event summary
No injuries to personnel.
The furnace suffered damage estimated at £10,000 (1973), including four distorted tubes and certain refractory damage. Some cabling, electrical and instrument fittings on the outside of the heater were also badly burnt.
Lesson Learnt
- Corrective Measures
1. Keep the 4" cold circulation start up valve locked in the `shut' position when the unit is on-stream and attach a `Danger, Valve Not to be Opened' tag to the valve wheel.
2. Fit tube skin thermocouples with maximum temperature alarms to the furnace to give warning of overheating.
In-depth data
- Release type
- gas mixture
- Involved substances (% vol)
- H2, hydrocarbons
- Probable IGNITION SOURCE
References
- Sources categories
- ICHEME
- Reference & weblink
Event description extracted from the UK database ICHEME in PDF
https://www.icheme.org/knowledge/safety-centre/resources/accident-data/
(accessed October 2020)
