Biological desulfurization in salty, alkaline conditions is used globally to eliminate hydrogen sulfide (H2S) from sour gas. This process uses bacteria that oxidize H2S into elemental sulfur (S8), which can be collected and reused. There are many different “knobs” that operators can use and understanding how these factors influence the system can enhance the biological desulfurization process.
In an anaerobic reactor, bacteria can remove (poly)sulfides (Sx2−). The bacteria’s activity is influenced by the oxidation-reduction potential (ORP) and pH levels. This study examined how these factors impact polysulfide concentration and chain length, finding that higher pH levels increased polysulfide concentration, while ORP changes had minimal effect. Polysulfide chain length distributions varied from those in non-biological systems at different pH levels. Finally, there was no combined effect of ORP and pH on the total polysulfide concentration. These understandings can enhance the efficiency of biological desulfurization processes since balancing polysulfide removal and production appears to be crucial for optimal sulfur production.
Read more:
Johnston, K. A. K. Y., van Lankveld, M., de Rink, R., Mol, A. R., Keesman, K. J., & Buisman, C. J. N. (2024). Influence of oxidation–reduction potential and pH on polysulfide concentrations and chain lengths in the biological desulfurization process under haloalkaline conditions. Water Research, 259(121795), 121795. https://doi.org/10.1016/j.watres.2024.121795