Power Cut at a Refinery Causes a Oil and Hydrogen Fire
The utility production facilities (electricity, water, air, and steam) at a refinery were isolated from the power grid and switched to two turbine generators in anticipation of a storm. At 9:50 p.m., both turbine generators shut down at the same time. Deprived of the necessary water and air, the boilers and all the production units entered a safe state. 1. The effluents drained from the stopped units were sent to detention ponds. 2. The gases were directed to the flare stack. A leak of burning hydrogen and petrol occurred in one of the units. The facility was restarted over the course of several days, but efforts were plagued by incidents due in particular to thermal fluctuations (pump breakage, water leak, steam leak, clogs, boiler with a punctured heating source). The burning leak, which was quickly brought under control, may have been caused by differential thermal stresses applied to the tightening bolts of the two companion flanges and significant pressure fluctuations that occurred when the units transitioned to a safe state. The temperature difference caused by the cooling inertia of the connected facilities and the thickness of the ring joint facilitated the loss of hydrogen. The cascade shutdown of the turbine generators was due to the control system, which failed because of an improperly connected electronic circuit board and a lack of pressure in the hydraulic circuit.
Event Date
August 7, 2013
Record Quality Indicator
Region / Country
Event Initiating System
Classification of the Physical Effects
Nature of the Consequences
Cause Comments
The immediate cause of the hydrogen leak was probably the failure of ha flanges join, subjected to thermal and pressure fluctuations occurred during the shutdown of the production units. The unplanned shutdown was caused by the failure of the emergency auxiliary systems was caused by an improperly connected electronic circuit board and a lack of pressure in the hydraulic circuit.
Facility Information
Application Type
Application
Specific Application Supply Chain Stage
Components Involved
unspecified production unit of a refinery
Storage/Process Medium
Location Type
Location description
Industrial Area
Pre-event Summary
The utility production facilities (electricity, water, air, and steam) at a refinery were isolated from the power grid and switched to two turbine generators in anticipation of a storm. Both turbine generators shut down at the same time. Deprived of the necessary water and air, the boilers and all the production units transitioned to a safe state. The effluent drained from the units that shut down was sent to detention ponds. Gas was directed to the flare stack.
Lessons Learned
Lessons Learned
Unknown
Event Nature
Emergency Action
The burning leak was quickly brought under control. The inspection authorities for classified facilities, the local residents, and the media were informed.
Detonation
No
Deflagration
No
High Pressure Explosion
No
High Voltage Explosion
No
Source Category
References
References
ARIA data base
event no. 44185