Cyclohexane Flixborough accident

The accident at Flixborough, England, is a classic example of a VCE. A sudden failure of a 20-inch cyclohexane line between reactors led to vaporization of an estimated 30 tons of cyclohexane. The vapor cloud dispersed throughout the plant site and was ignited by an unknown source 45 seconds after the release. The entire plant site was leveled and 28 people were killed. 

Finite-element and computational fluid dynamics analyses of the accident at the NYPRO Works at Flixborough have been conducted. The results suggest that the cause of the catastrophe was flow-induced fatigue of one of the bellows forming the bypass assembiy that resulted in the initiation of a complex sequence of events that released only 10 to 16 tons of cyclohexane to form an unconfined vapor cloud that was detonated. 

The second example marked with a square is the well-known accident of Flixborough, where a vapor cloud explosion occurred after jet release of hot cyclohexane into an industrial environment. 

This accident occurred on June 1, 1974 at the Flixborough Works of Nypro (United Kingdom) Limited when a bypass system ruptured and released cyclohexane, which in turn formed a combustible mixture with air and then exploded on coming in contact with an ignition source [1,10,11]. As the result of this accident, 28 workers were killed and 36 injured [1,10,11]. Two of the active influencing maintenance factors were as follows [1,10] ... 

On June 1, 1974, an accident occurred in the Nypro plant in Flixborough, England, in a process where cyclohexane was oxidized to cyclohexanone for the manufacture of caprolactam, the basic raw material for the production of Nylon 6. The process consisted of six reactors in series at 155°C and 8.8 bar (130 psig) containing a total of 120 tons of cyclohexane and a small amount of cyclohexanone. The final reactor in the process... 

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