A leak occurred in a chemical plant at around 12:10 a.m. on a level sensor connection on a 10 m³ tank containing 2 m³ of a bromide and bromine solution at a concentration of less than 2%. The plant’s fire-fighters were able to confine the leak with water curtains. The bromine present in the aqueous effluents was neutralised by a hyposulphite treatment until the tank was completely drained. Air toxicity measurements were conducted. A solid plug made of PVDF (polyvinylidene fluoride – a thermoplastic fluoropolymer) was installed on the leaky branch connection. Thirteen employees fell ill after being exposed to the bromine vapours: eye irritations and headaches. They were treated at the site’s infirmary and were able to return to work after an hour. The water used during this operation was collected and processed in the site’s wastewater treatment facility. It is estimated that approximately 57 kg of bromine was lost. The operator issued a press release.
The leak on the connection was located on a stainless steel flange. The lower part of the flange had become cracked as a result of a regular corrosion phenomenon. The use of non-bromine-compatible material was determined to be the cause of this corrosion.
The operator installed a level sensor that can be isolated via a PVDF valve on the tank. Following this event, an inspection was conducted to ensure that the pipe class was respected for all lines conveying bromine, concentrated or otherwise.