Explosion at the catalytic reformer unit of a refinery

A fire and explosion occurred at a catalytic reformer unit. The fire centred between the reactors and fired heaters of the reformer and resulted in extensive damage to the unit.

The explosion rocked the nearby refinery control centre and broke windows half a mile away. There were no injuries. After the explosion, the operating crew isolated all hydrocarbon and utilities lines at the unit battery limit. The columns and vessels could not be pumped out due to total loss of power. A 750 gpm stationary monitor located north of the unit was directed on the affected pipeline to cool down and prevent further failures.

The fire caused major damage to four reformer heaters, piping, wiring, instrumentation and structures in the area.

After investigations into the cause of the incident it was found that metallurgical failure probably caused by hydrogen attack was to blame. Metallurgical analysis revealed that high temperature hydrogen attack occurred in various forms throughout the steel lines.

According to the ICHEME report (see references), the INITIATING cause was the localised failure of a pipe due high temperature hydrogen attack.

Since the post-event metallurgical investigation identified the hydrogen attack in various forms throughout the steel pipelines, it can be assumed that the ROOT CAUSE was a wrong material choice.

reformer, reactors and reaction equipment

There were no injuries.
The fire caused major damage to four reformer heaters, piping, wiring, instrumentation and structures in the area.
The explosion rocked the nearby refinery control centre and broke windows half a mile away.

Since the year of the accident, technologies have made considerable progress in understanding the mechanisms underlying hydrogen damage, from embrittlement to high temperature attack. This assisted in developing and improving guidelines and procedures facilitating the choice of and design with the correct steel types in presence of (cold and hot) hydrogen.