Sub-Product

Sulfur is recovered by converting H₂S to Elemental Sulfur. Sulfur recovery takes place in a series of two steps: Claus Process and SCOT Process. In the Modified Claus Process, partial combustion of H₂S takes place to generate SO₂ that is reacted with the remaining H₂S to recover Sulfur as Elemental Sulfur. The Modified Claus Process, once-through burner operation, works only with acid gases that contain more than 50% H₂S by volume. In the process, Hydrogen in H₂S is converted to H₂O. The second stage, the SCOT Process, functions as a Tail Gas clean-up operation to remove the Sulfur compounds produced in the side reactions of the Claus Process, i.e., Carbonyl Sulfide (COS) and Carbon Disulfide (CS₂).