Large-scale sulfur removal making the claus process obsolete.

This hybrid process concept currently under development places a direct oxidation catalyst bed upstream of the CrystaSulf^SM unit. This approach allows 80-95% of the H₂S in the inlet gas stream to be converted to elemental sulfur and removed in a sulfur condenser before entering the CrystaSulf absorber. The beneficial impact on the CrystaSulf unit is to reduce circulation rate and size of the crystallizer, sulfur filter and associated equipment by 90% or more. Consequently, utilities and chemicals consumption rates are reduced dramatically. Further, the SO₂ needed for the liquid phase reactions in CrystaSulf can be produced in the same catalyst bed, simplifying the process and lowering its cost even more. Overall capital and operating cost reductions of 50-60% are achieved with CrystaSulf-DO. The CrystaSulf-DO approach offers a significant cost advantage versus the amine/Claus/tail gas approach for applications up to 250 TPD.