4. Example of application to a tank in an ammonia production plant

The equipment used as an example concerns a tank in an ammonia production plant, the schematic diagram of which is shown on figure 13 . Following the Haber process, ammonia is obtained by hydrogenating nitrogen with hydrogen in the presence of an iron-based catalyst contained in the reactor operating at high temperature (400°C) and also at high pressure (200 bar). The ammonia gas is then cooled by a condenser to liquefy it for storage prior to its final use. The toxicity of gaseous ammonia depends on its concentration and the length of time people are exposed to it, and is likely to lead to lethal or irreversible effects. In France, these industrial facilities are classified as SEVESO due to the risks to health and the environment in the event of ammonia gas release following loss of containment....