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SmartSulf® (formerly known as ClinSulf™ or DegSulf™) is a breakthrough sulfur recovery process, using proprietary isothermal reactor technology, which enable sulfur recovery yields up to 99.5% in a two catalytic stages claus process configuration.

Process Scheme

Process Principle

  • Thermal stage: acid gases are burnt with air to produce sulfur at high temperature thanks to Claus reaction.
  • COS and CS2 hydrolysis: COS and CS2 from the process gases are hydrolyzed at high temperature in the first zone of the SmartSulf® reactor operating in hot mode.
  • Claus reaction: Claus reaction occurs in the second zone of the hot mode SmartSulf® reactor where heat of reaction is continuously removed by thermoplates internals, thus increasing sulfur conversion.
  • Subdewpoint Claus reaction: Claus reaction is performed in the cold mode SmartSulf® reactor operating below sulfur dewpoint and producing liquid sulfur which is trapped on catalyst.
  • Cycle switch: when cold mode SmartSulf® reactor is saturated with liquid sulfur, a switch between hot and cold mode is performed automatically by rotating the two coupled 4 way valves, enabling the beginning of a new cycle.

Key Benefits

  • Performance above 99.5% sulfur recovery
  • Complete COS and CS2 destruction at high temperature
  • Proven technology, successfully operating in commercial plants since 1995
  • Very low capital cost
  • Low operation cost: process is fully automatic and nearly needs no follow-up
  • Use of conventional open market Claus catalysts
  • Easy retrofit to upgrade existing Claus units into SmartSulf®

Industrial References

There are currently 17 references using SmartSulf® technology

80 TPD SmartSulf® unit at RIAMA Refinery, Salamanca - Mexico

Documentation Center

SmartSulf - Commercial Bulletin cadenas

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