A sulfur recovery unit converts the hydrogen sulfide in the acid gas into elemental sulfur. Of the processes available for these conversions, the Claus process is by far the most well-known for recovering elemental sulfur, whereas the conventional Contact Process and the WSA
Process are the most used technologies for recovering sulfuric acid. The residual gas from the Claus process is commonly called tail gas. Tail gas is subsequently processed in a gas treating unit.
The sulfur condenser vessel is equipped with a disengagement section on the outlet end in order to allow for efficient separation of the liquid sulfur from the process gas. A collection vessel equipped with continuous level control is used to store and remove the sulfur product from the process.