The accident occurred during the night during the production of a silicon oil- and additive-based waterproofing agent. A junior technician (hired 6 months back), recently assigned to this post, was left without supervision to manage a process modified very recently and executed only for the second time. In the process, the order of addition of reactants was not specified. The technician loaded first 800 kg of oil into the tank at first floor, started heating the reactor, and descended to the ground floor to pump the reagent.

SUMMARYThe explosion occurred in a catalyst regenerator of the catalytic cracking unit in a fluidized bed during a technical shutdown. A few seconds later, a second explosion is perceived, it is the pressure wave of the first explosion which reached the site recovery boiler 30 m away and connected to the regenerator by pipe. It left 24 people injured; 8 were hospitalized, including 2 suffering from severe burns.

This resulted in the destruction of the building where the explosion occurred and claimed the lives of two people. The triggering event was a blowing out of a gasket in a water pump situated in a 100 m long, 10 m wide and 7 m high building. The pump fed water to a vessel that contained hydrogen gas at 30 bars. The pressure caused a back flow of water flow through the pump and out of the failed gasket. The hydrogen reached the leakage point after approximately 3 minutes. The discharge of gas lasted 20 - 30 seconds before the explosion.