Effect of liquid surface area on hydrogen sulfide oxidation during micro-aeration in dairy manure digesters

Although there are a variety of commercially available biological and chemical treatments for removal of hydrogen sulfide (H2S) from biogas, managing biogas H2S remains a significant challenge for agricultural digesters where labor and operational funds are very limited compared to municipal and industrial digesters. The objectives of this study were to evaluate headspace aeration for reducing H2S levels in low cost plug flow digesters and to characterize the relationship between the liquid surface area and H2S oxidation rates. Experiments with replicate field scale plug flow digesters showed that H2S levels decreased from 3500 ppmv to