Explosion at a Hydro-Treatment Unit of a Refinery
In a residual-oil hydrotreatment unit (also called residual oil hydrogenation) plant, a hydrogenation unit caught fire with a huge bang, followed by a fireball in the form of a mushroom cloud. Black smoke began to billow up in the sky and was clearly visible from several kilometres away
Event Date
December 13, 2021
Record Quality Indicator
Region / Country
Event Initiating System
Classification of the Physical Effects
Nature of the Consequences
Causes
Cause Comments
Both immediate and root causes are unknown. Although it is probable that hydrogen was at least one of the flammable gases contributing to the starting of the fire, without knowing the causes it is not possible to conclude on the role of hydrogen.
Facility Information
Application Type
Application
Specific Application Supply Chain Stage
Components Involved
hydrogenation unit
Storage/Process Medium
Location Type
Location description
Industrial Area
Operational Condition
Pre-event Summary
PROCESS EXPLANATION:The hydrotreatment process is also called residual oil hydrogenation. Residual oil is the residue remaining after the distillation and processing of petroleum. Oil hydrotreatment refers to the purification of the oil from harmful impurities such as sulfur, nitrogen, and metals. In presence of a catalyst, the hydrogen reacts with these components, forming hydrogen sulfide, ammonia and metal sulfides. At the same time, some of the larger molecules of the residual oil are cracked and hydrogenated into smaller molecules, which also react to produce metal sulfides.
Lessons Learned
Lessons Learned
Unknown
Event Nature
Emergency Action
the fire started at 9:43am, the city fire fighting service immediately responded, and the fire was extinguished at 11:20 am (in 1 hour 37 minutes).
Ignition Source
Detonation
No
Deflagration
No
High Pressure Explosion
No
High Voltage Explosion
No
Source Category
References
References
“Electric horse” Web-news of 17 December 2021, available at
https://mp.weixin.qq.com/s/VXAhZhm4BDdUrLuY9cN5kA
(last retrieved 20.02.2023)
B.Wang et al., Hydrogen related accidents and lesson learned, submitted to ICHS-2023