Explosion of a hydrogen tank in a steel manufacturing plant.

an explosion occurred in a hydrogen storage tank at the hydrogen station of the oxygen plant of the energy centre.
The 10 m3 hydrogen storage tank at the hydrogen station belonging to the oxygen plant exploded during production operation. The hydrogen storage tank was installed and used by the plant in 1995, with a design pressure of 1,5 MPa, a volume of 10 m^3, a minimum wall thickness of 12 mm, a total length of 4576 mm (height) and an inner diameter of 1800 mm. After the explosion, there were no metal components left, except for the cement prefabricated foundation of the tank base. The main body of the hydrogen storage tank ruptured into 10 pieces, with most of the debris flying away from the site and all debris scattered separately within a 300m radius from the centre of the explosion; 46 pieces of debris were collected.

The results of this test determined that the electrolytic cell was misconnected between positive and negative electrodes during inspection and maintenance (replacement) works. It is suspected that the electrician inverted the electrodes when replacing the cables. This led to an interchange in the hydrogen and oxygen production system

The INITIATING CAUSE was the injection of oxygen into the hydrogen flow at the electrolyser.
It is suspected that the electrician inverted the electrodes when replacing the cables. This led to an interchange in the hydrogen and oxygen production system
The ROOT CAUSE could be a combination of a human error and/or ill designed maintenance procedure, up to management failure

storage tank

A similar accident seems to have taken place in the same installation 5 years ago.

DESCRIPTION OF THE UNIT
The hydrogen storage tank was installed and used by the plant in 1995, with a design pressure of 1,5 MPa, a volume of 10 m^3, a minimum wall thickness of 12 mm, a total length of 4576 mm (height) and an inner diameter of 1800 mm.

No one was injured.
The buildings within approximately 200 m of the centre of the explosion glass was mostly broken. Windows and doors within approximately 100 m suffered varying degrees of damage of varying degrees. Nearly 10 m of the wall to the north-east of the centre of the explosion collapsed.