Fire on the Hydrodesulfurization Unit of a Refinery (1066)

Around 4 a.m., a major leak occurred at the outlet of the diesel hydrodesulfurization furnace in a refinery. The goal of this unit is to lower the sulfur content of diesel fuels produced in other units, by a catalytic reaction in the presence of hydrogen. At the moment of the leak the furnace was restarting. The alarms of the temperature sensors at the oven outlet were triggered. At 4:08 a.m., the operator shut down the hydrogen compressors and diesel charging pumps, closed the supply valves and called the emergency status. The first emergency operation was to decompress the unit.