The EUROCLAUS® process has been developed to recover elemental sulfur from H2S containing gases originating from gas treating plants such as alkanolamine units or physical solvent plants. The EUROCLAUS® process is an improvement of the SUPERCLAUS® process. Yields up to 99.5% overall sulfur recovery without any further tail gas clean up are possible,
The EUROCLAUS® process consists of a thermal stage followed by three or four catalytic reaction stages with sulfur removed between stages by condensers. Two first two or three reactors are filled with standard Claus catalyst while the last reactor is filled with the selective oxidation catalyst. In the thermal stage, the acid gas is burned with a substoichiometric amount of controlled combustion air such that the tail gas leaving the last Claus reactor contains typically 0.8 to 1.0 vol.% of H2S and 100-200 ppmv SO2. This low SO2 content is obtained with a hydrogenation catalyst which converts SO2 to H2S in the bottom of the last Claus reactor. The SUPERCLAUS® catalyst in the final reactor oxidizes the H2S to sulfur at an efficiency of more than 85%. A total sulfur recovery efficiency up to 99.4% can be obtained with three reactor stages and up to 99.5% with four stages.
Three main principles are applied in operating the EUROCLAUS® process:
- Operating the Claus plant with excess H2S to suppress the SO2 content in the Claus tail gas.
- Selective reduction of SO2 in the Claus process gas by means of a catalyst with hydrogenating properties.
- Selective oxidation of the remaining H2S in the Claus tail gas by means of special catalyst which efficiently converts the remaining H2S in the presence of water vapor and excess oxygen to elemental sulfur only.
Other operating features, which apply to Jacobs Comprimo's Claus process also apply to the EUROCLAUS® process. These include NH3 destruction up to 30 vol.%, the capability to process small amounts of heavy hydrocarbons and aromatics up to 2 vol.%, turndown ratios of 100-15%. Producing 99.9% pure bright yellow sulfur.
- Application in both new and existing plants.
- The SUPERCLAUS® catalyst as applied in the SUPERCLAUS® process.
- A final Claus reactor also containing hydrogenation catalyst.
- Long catalyst lifetime up (over 5 years)
- Sulfur recovery up to 99.5%.
- Reduction of SO2 emissions by up to 90%.
- Simple continuous operation.
- Low additional investment costs.
- NH3 destruction.
- Capability to combust heavy hydrocarbon and aromatics.
- High turndown.
- High reliability - less than 1% unscheduled shutdown time
Since the first commercial demonstration of the EUROCLAUS® process in 2000, more than 40 plants are in operation or under construction.
Jacobs Nederland B.V., Leiden, The Netherlands, and Jacobs Canada, Calgary together forming Jacobs Comprimo® Sulfur Solutions.