Sulphur Recovery Unit Operations

• Sulphur Recovery is the unit operation of converting H2S into elemental Sulphur by the Modified Claus Process
• The source of the H2S can be Sulphur in refinery crude oil, converted to H2S in an upstream process.
• Hydrodesulferization (the HDS unit where S + H2 converts to H2S)
  • H2S as it exits in natural gas (already as H2S, no need for HDS)
  • Elemental Sulphur in coal converted to H2S in coking/coal gasification
  • H2S as a byproduct in chemical plants, typically CS2 for rayon production
• Upstream process of removing H2S is Amine Treating
• Downstream process to reduce emission is Tail Gas Treating
  • Emissions can also be reduced by Enhanced Claus Processes