At around 10:00 p.m., a technician smelled a characteristic burning odour at a plant that processes sunflower seeds used in the food industry, the agrifood industry, and the energy industry. He discovered a fire inside a bag filter located at the foot of an elevator used to supply seed hulls to the concrete bin of a silo (height: 50 m). He alerted his shift supervisor and shut down the elevator. While attempting to bring the fire under control, they saw smoke exiting the storage bin that contained 800 tonnes of hulls and called the public firefighters (11:05 p.m.). The internal emergency plan was implemented. The employees were evacuated and the power supplies were cut off. The operator inerted the storage bin with nitrogen and the firefighters sprayed foam over the surface of the seeds. The carbon monoxide levels, oxygen levels, temperature levels, and explosive conditions were regularly monitored. The emptying of the silo began during the night and was halted at 5:45 a.m. on 3 November because the pumping by a road tanker was not sufficient. The hulls were then emptied by a rental conveyor belt (20 tonnes per hour) during the afternoon of 4 November. Emptying was continued the following morning with a Redler chain conveyor (30–40 tonnes per hour). After the silo’s discharge auger became clogged on 5 November, a 0.6 × 0.6 hole was drilled into the 0.20 m reinforced concrete wall at the bottom of the storage bin. A special nozzle, designed to penetrate into the centre of the combusted mass, was used to unjam the auger and create a dia. 1 m hole in the grain that made it possible to see the top of the silo. The firefighters left at around 4:00 p.m. on 8 November. The 40 tonnes of grain remaining inside along a height of 4 m was removed by the operator.

A total of 9.5 m³ of foam compound was required for the blanket of foam kept inside the storage bin until the evening of 4 November. The silo was inerted nitrogen via the bottom, then the top in order to inert the vapour space. This inerting was accomplished first using the site’s stockpile of process gas, then gas brought in by outside suppliers.

The firefighters had to contend with a number of problems that included getting the emulsifying agent all the way to the top of the silo, the quality of the emulsifying agent provided by outside help; a technical problem with the dry standpipe that meant that a hose had to be used instead; the diameters of the pipes at the facility were not the same as those used by the firefighters; the nitrogen road tanker brought to the site did not have a reheater; problems in obtaining new supplies of nitrogen; and the grain became clogged by the extinguishing water and foam.

According to the operator, the fire may have been caused by self-heating inside a hull processing hopper upstream of the storage bin. The start of combustion had been extinguished inside it at around 10:00 a.m. on 3 November before smoke appeared. The operator conducted an in-depth analysis of the accident’s causes, amended its emergency response procedure with the assistance of the emergency response service, and developed plans to improve the detection of hull hot spots prior to storage in the silos.