Hydrogenation/Amine Tail Gas Treating Technology

Hydrogenation/Amine Tail Gas Treating Technology


Fluor's proprietary hydrogenation/amine tail gas treating process is a proven process widely employed in the industry. The hydrogenation/hydrolysis section converts SO2, COS, CS2, elemental S and other sulfur species in the Claus tail gas to H2S. The hydrogenated gas is then sweetened by a selective amine to remove H2S. This add-on process follows a two or three stage Claus SRU to achieve overall sulfur recovery of up to 99.99%.

Fluor's proprietary Tail Gas Treating technology features the state of the art Low Temperature CoMo catalyst, which operates at lower temperature than conventional CoMo catalyst. The lower operating temperature eliminates the requirement of the fired heater, Reducing Gas Generator, and thus, simplifies operating and enhances performance and catalyst life. For certain applications, conventional CoMo catalyst using a Reducing Gas Generator can be offered if desired.

A two-stage quench tower (desuperheater/contact condenser) is employed in Fluor's proprietary design. The lower section contains a circulating stream of caustic solution to guard against any SO2 breakthrough from the upstream reactor, which would otherwise degrade the downstream treating solvent.

Generic or formulated MDEA can be used in the amine section of the tail gas treating unit to achieve up to 99.99% overall sulfur recovery. Fluor also offers the FLEXSORB™ SE and SE Plus Technology, which is a hindered amine with extremely high selectivity toward H2S to provide significant reduction in solvent circulation and ultra-high treating performance.

Depending on the solvent used, H2S level in the treated gas from the tail gas treating unit can be as low as 10 ppm which can be discharged directly into the atmosphere, therefore, eliminating the requirement of a thermal oxidizer.

Client Benefits

The benefits of Fluor's proprietary tail gas treating unit technologies include:

  • Highest achievable overall sulfur recovery efficiency of up to 99.99% to meet the most stringent environmental requirement
  • Capital and operating costs savings when utilizing formulated MDEA in which flue gas can be directly discharged to the atmosphere. Thus eliminating the requirement of a thermal oxidizer for capital and operating costs savings.
  • Proprietary configuration with Low Temperature CoMo catalyst and two stage quench tower (desuperheater/contact condenser) for savings in capital/operating costs as well as enhanced safety, flexibility and reliability.
  • FLEXSORB™ SE/SE Plus Technology has a high H2S selectivity, ensuring it is capable of achieving a sulfur recovery efficiency rate of more than 99.99% overall, with a lower solution circulation rate (60%) compared to formulated MDEA solvent. It is operable in high temperature environments, including arid and dessert environments, such as the Middle East region.
  • Fluor has built over 100 tail gas treating units to date and thus have extensive experience to provide the most cost effective configuration for any application to meet the most stringent environmental regulations.