HCL leak incident

In a sulphur dichloride (SCl2) distillation facility in a chemical plant, a spillage of SCl2 occurred in the retention area for a distillation column in the final stages of distillation, after a leak from a recirculating pump. The SCl2 hydrolysed upon contact with ambient humidity, causing an intensive emission of hydrogen chloride (HCl), which was not detected by the HCl gas detector of the column. But a safety detector installed in the unit gives the alarm at 13:12. The controller placed the unit in safety shut down and then triggered locally the audible and visual alarm while alarm messages appear on the control screens in the control room. The internal emergency plan was activated and the 35 employees were evacuated. The internal fire team, supported by 40 external firefighters, equipped themselves with breathing apparatus and plugged the leak. The cloud of HCl was overcome using 4 lateral fire hose lines. The 120 m³ of water used is collected in a retention pond for reuse in production. The internal emergency plan is terminated at 16:15 pm. The next day a specialized company pumped 800 liters (1,200 kg) of sulfur dichloride from the retention basin into a storage tank. The HCl release remained confined inside the building. 

Source:European commission