ENV-06-154 DynaWave Wet Gas Scrubbing: A New Alternative for Claus Unit Tail Gas Treating

Description:

Until recently, there were few viable alternatives to this approach to SRU tail gas treatment that could also provide an overall sulfur recovery/removal of 99.8% or better. However, recently a wet gas scrubber was shown to be a viable, alternate approach for SRU tail gas treatment. When using a wet gas scrubber, the sulfur compounds present in the tail gas from the Claus Unit are first oxidized to SO2. The SO2 is then captured by contacting the gas stream with an alkaline reagent such as sodium hydroxide in the wet gas scrubber, producing a concentrated brine waste stream. Residual SO2 not captured in the scrubber is discharged to the atmosphere. With this approach, there is no H2S recycle to the sulfur recovery unit, and the overall sulfur recovery/removal efficiency is increased to 99.95%. In addition, equipment costs for a wet gas scrubbing system are less than conventional amine absorption type systems. Finally, wet gas scrubbing systems can operate over the wide range of feed conditions found in refineries and gas plants, including upset conditions.