Oxygen Based Claus Process for Recovery of Sulfur from H2S Gases

Novel oxygen‐based modifications of the Claus process for sulfur recovery from gases containing hydrogen sulfide are analyzed and compared with the conventional air‐based technology. Oxygen‐based modifications include systems with air enrichment by oxygen, with oxygen‐air‐water oxidizers, with recycle of cooled products from boilers back into the Claus furnace, and systems with consecutive or parallel‐consecutive Claus furnaces. The analysis used in this work involves the process thermodynamics and kinetics, as well as modeling of the entire system. The thermodynamics was evaluated using the STANJAN chemical equilibrium solver program, which utilizes the principle of minimization of free Gibbs energy. The process kinetics was evaluated using published data on full‐scale Claus systems. The performance of various process modifications was evaluated by the use of numerical analyses. The major findings of the work are that oxygen‐based Claus systems can be used for: (1) Upgrading existing systems and for use ...