How can you meet World Bank standards for sulphur emissions?

The Claus unit design is based on the experience of decades of operation across Shell and focuses on reliability and safety with high conversion. By adding the SCOT process, you can achieve sulphur recovery levels as high as 99.98% or less than 150 mg /Nm3 SO2.

Well-operated Claus tail gas units are required for today’s refineries and gas plants to meet strict environmental regulations.

The SCOT process catalytically converts the remaining sulphur dioxide in Claus tail gas to hydrogen sulphide. Hydrogen sulphide is then stripped from the tail gas and reprocessed.


  • Sulphur recovery up to 99.9+%;
  • Excellent reliability: <1% unscheduled downtime in Shell-advised units;
  • The low-sulphur SCOT process produces <10 ppmv hydrogen sulphide in off-gas;
  • High flexibility: <10% turndown ratio;
  • World Bank SO2 emission levels met; and
  • Low maintenance requirements.

More In Licensed Technologies

Sulphur Recovery

Reliable and robust operations with Claus, SCOT, sulphur degassing and THIOPAQ O&G sulphur recovery technologies to secure gas production and ensuring the need to adhere to stringent sulphur dioxide (SO2) standards.

Contact Gas Processing

Please contact the Shell Gas Treating and Sulphur Removal technologies team for further information and we will respond to your enquiry via email.