Around 3.30 pm, in an ammonia production plant, a flaming leak of hydrogen occurs on a pressurised separator on a gas synthesis line. The flaming jet from 10 m se spreads to surrounding equipment, igniting those containing oil. The jet is stopped by closing a valve located upstream of the hydrogen leak. The emergency response team cools the equipment next to the jet and brings the fire under control at around 4.10 pm. The civil protection carries out checks on the ambient air, which prove to be negative, in order to verify the absence of ammonia.

During the leak, 700 kg of hydrogen is released. Major damage is caused in the factory premises. The plant is closed for several months to carry out repairs. Damages related to material losses amount to €9 million.

At the origin of the flaming jet, the hydrogen leak is located on the connection between the separator and its level measuring instrument. It occurred during the shutdown of the compressor of the gas synthesis line due to a malfunction. A slight increase in upstream pressure occurs (25 to 29 bar). The line is protected by a valve set at 30 bar. However, a pressure of 29 bar has proved to be sufficient to cause the connecting hose between the separator and the measuring instrument to rupture. This pipe showed significant wear due to undetected corrosion under the insulation.

Following the accident, the operator is planning to improve the inspection system for insulated piping. It is installing an automatic extinguishing system in the compressors and moving equipment containing oil.