Assessing Different Inoculum Treatments for Improved Production of Hydrogen through Dark Fermentation

Hydrogen gas (H2) is an energy carrier that does not generate carbon dioxide emissions during combustion, but several processes in use for its production demand high inputs associated with fossil fuels and greenhouse emissions. Biological processes, such as dark fermentation (DF), have the potential to remove dependency on H2 production. DF a process encourages fermentative bacteria ferment organic substrates produce truly clean carrier, success depends removing presence of competing H2−consuming microorganisms inoculum consortia. This paper addresses strategy enhance from different types by testing pre-treatment inactivate bacteria, including acid-shock (pH 3), basic-shock 10) heat-shock (115 °C) methods. Digestate anaerobic digesters processing sewage sludge was used pre-treated inocula, which were subsequently tested batch bio-H2 (BHP) test using glucose substrate. The results show best method, reporting yield 191.8 mL-H2/gVS added (the untreated reported 170.91 added). Glucose conversion data concentration butyric acid both treated inocula BHP tests, indicate butyrate pathway dominant; shifting this formate route could further net A standardised inoculum-conditioning method can help consistently assess biohydrogen suitable feedstock maximise yields.