Fire on a Methanation Reactor
The methanation reactor vessel was found to be deformed and had a 3-4 inch rupture at a position corresponding to the top of the catalyst bed. It is though that the incident was caused by ethylene entering the reactor. The ethylene reacted with hydrogen on the nickel catalyst, resulting in a very rapid release of energy. The corresponding temperature rise was sufficient to cause a ductile failure of the vessel.The proposed mechanism for the reaction is that ethylene vapour entered the methanation reactor via the cold box where there was a low pressure/high temperature following the trip. On re-pressuring, the ethylene was carried forward through the 90% hydrogen line to the reactor.
Event Date
August 23, 1990
Record Quality Indicator
Region / Country
Event Initiating System
Classification of the Physical Effects
Nature of the Consequences
Cause Comments
According to the ICHEME report (See References), the assumed immediate cause was a runaway reaction caused by the accidental injection of ethylene into the methanation reactor. The proposed mechanism for the accident is that ethylene vapor entered the methanation reactor via the cold box where there was a low pressure/high temperature following the trip. When re-pressuring, the ethylene was carried forward through the 90% hydrogen line to the methanation reactor.
Facility Information
Application Type
Application
Specific Application Supply Chain Stage
Components Involved
methanator
Storage/Process Medium
Location Type
Location description
Industrial Area
Lessons Learned
Lessons Learned
No lesson learned was reported in the ICHEME database, and the level of details available does not allow for general conclusion. This type of accidents was already occurred in the past.
Event Nature
Emergency Action
Unknown
Detonation
No
Deflagration
No
High Pressure Explosion
No
High Voltage Explosion
No
Source Category
References
References
Event description extracted from the UK database ICHEME in PDF.
The ICHEME database is no longer available for purchase, but data can be download as PDF for free.
https://www.icheme.org/knowledge/safety-centre/resources/accident-data/
(accessed October 2020)