A fire broke out affecting the heavy fuel purification plant of the refinery.The incident could have originated by the failure of one of the following plant components:- pipes leading to the pressure gauges of the reactor - recycled gas pipe at the bottom of the reactor having a quench function,- diatermic oil pipe (hot oil) entering or exiting the exchanger- flanged joints exchanger and connection lines.On the base of and data logging and video evidences, the company excludes a release from the hot oil circuit as the triggering factor of the fire.

The incident affected at an indirect oil desulfurization unit, and originated at a piping at the outlet of a heat exchanger. The exchanger was located in the furthermost downstream of the reactor. The dead-end cap of the piping failed due to corrosion and opened, releasing high-pressure hydrogen which leaked, ignited and exploded. Due to the explosion, the heat exchanger was damages and oil leaked out contributing to spread the damage. Approximately 1200 kg of hydrogen and 30000 l of oil were burned. No injuries.