Leakage in an Ammonia and Fertilizers Plant
A hydrogen leakage occurred in the ammonia workshop of a plant manufacturing nitrogen products and fertilizer (classified SEVESO high threshold). It was detected by an operator in charge of safety checks, by the noise and by his portable gas detector. After confirming the leak, the operator stopped the piping (30 bar) to repair it. The ammonia workshop was also partially shut down. The operator closed the section at the origin of the leak by installing a threaded and welded plug.The leak was due to corrosion under insulation on a DN50 dead arm: a 90 elbow punctured on DN400 piping. The control plan for the piping was not foreseeing the removal of the insulation of this section. The Classified Installations Inspectorate requests the RIS (Recognized Inspection Service) to review these plans to check sensitive areas of piping throughout the plant.
Event Date
July 24, 2018
Record Quality Indicator
Region / Country
Event Initiating System
Classification of the Physical Effects
Nature of the Consequences
Cause Comments
The leak was due to corrosion under insulation on a DN50 dead arm: a 90 elbow punctured on DN400 piping. The control plan for the piping was not foreseeing the removal of the insulation of this section.
Facility Information
Application Type
Application
Specific Application Supply Chain Stage
Components Involved
ammonia synthesis reactor, hydrogen pipe
Storage/Process Medium
Actual Pressure
30
Location Type
Location description
Industrial Area
Pre-event Summary
Carrying out safety checks in the ammonia workshop of a plant manufacturing nitrogen products and fertilizer (classified SEVESO high threshold), an operator detected by the noise and his portable gas detector, a leak on a pipeline carrying hydrogen gas.
Currency
Event Nature
Emergency Action
After confirming the leak, the operator stopped the piping (30 bar) to repair it. The ammonia workshop was also partially shut down. The operator closed the section at the origin of the leak by installing a threaded and welded plug.
Release Type
Release Substance
Hydrogen Release Concentration (%)
100.00
Detonation
No
Deflagration
No
High Pressure Explosion
No
High Voltage Explosion
No
Source Category
References
References
ARIA data base
event no. 51798