In a sugar refinery, 4 explosions and a basin fire occurred at 4:42 pm following tests on pumps run until 4:15 along with the transfer of 13 m³ of alcohol into a 1,500-m3 empty degassed tank. The internal emergency plan was activated at 5 pm: 120 employees and 90 fire-fighters were at the scene by 5:15 pm and deployed emulsifiers (some being incompatible) contributed by neighbouring industries. As of 5:38 pm, a sprinkler and water canon were protecting adjacent installations. The fire was extinguished at 5:42 pm, at 6:55 pm sprinklers were turned off, followed at 7:30 pm by lifting the internal emergency plan.

Operating losses were appraised at €2.13 million and property damage amounted to €2 million: a 1,500-m3 tank (whose structure collapsed) and a 540-m³ tank (roof blown off) were destroyed, while the roofs on three 115-m³ tanks were torn. The plant treated 2,000 m³ of extinction water. Installation compliance with the administrative order on the fire extinction network, stationary water/foam canons, emulsifier provisions, etc. enabled personnel to respond quickly; an emergency plan drill held in June based on a scenario similar to this incident facilitated this intervention. A few unfavourable aspects were still detected: failure to isolate the alcohol storage zone, presence of non-degassed tanks, manual start-up of stationary installations, and absence of a foam outfall.

From the completed appraisals, the tank explosion was due to ignition of an explosive atmosphere composed of alcohol vapours and air. This inflammation was caused by the highly exothermic reaction between surplus oxidant, potassium permanganate (KMnO4) and an aqueous 96% ethanol solution. As a result of the domino effect, the consequences of this accident were exacerbated by damage caused to the other tanks. Subsequent to this accident, prevention and intervention equipment was upgraded and, after process validation, the solid permanganate was replaced by diluted liquid permanganate.

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