Pollution
Humain
Environnement
Economique

In a grain cooperative, a fire broke out in a cooler treating 5 t of dried alfalfa before its packaging into 375 kg bales. At the time of the accident, the two drying lines in the combined production of dried alfalfa bales and pellets were in operation. Alerted by the ember detectors on the pellet handling circuits, the line operator and his assistant shut down the dryers in accordance with the procedures, but did not notice a simultaneous detection on the cooler whose ventilation system automatically shut down. At this stage of the process, the product that is dry and in the form of loose strands, constitutes a voluminous and highly flammable layer. Confronted with the risk of the fire spreading, the operator activated its internal emergency plan and alerted the public emergency services. The late discovery of the fire and poor knowledge of the fire protection systems delayed the technicians’ actions by 5 to 10 minutes. However, the fire had been contained before the fire-fighters had arrived using the spraying equipment installed in the cooler and back-up interventions using the first aid hose system. The installation was not damaged. The plant resumed its activities 12 hours later after an inspection and the cleaning of the circuits connected upstream and downstream of the cooler. The fixed spraying equipment and automatic shutdown of the cooler ventilation system proved to be effective, nevertheless the operator has now slaved the progress and the ventilation of the cooler to an ember detector installed further upstream on the feed auger. It is improving the production staff’s knowledge of the fire protection equipment and networks and carrying out fire drills.