Design of SRU Thermal Reactor and Waste Heat Boiler Considering Recombination Reactions

The first section of sulphur recovery units (SRU) based on Claus process is constituted of a burner, a thermal reactor and a waste heat boiler and it is designed to oxidize acid gases by air. Because of several oxidation reactions are reversible, as the gas is cooled in the boiler recombination reactions occur, modifying the heat exchange and gas composition. This may have a significant effect on the design of the waste heat boiler and downstream Claus reactors. In this study, the design of thermal reactor and waste heat boiler system is proposed by adopting a common model. The model, including a detailed kinetic scheme, considers recombination reactions in the boiler.