Enhancement of Bio-Hydrogen Production From Sewage Sludge and Fallen Trees Leaves via Anaerobic Bioreactor

Egypt faces significant challenges in managing sewage sludge (SS), which is generated in large quantities. This study investigates the feasibility of utilizing SS as a renewable resource for biohydrogen production through anaerobic digestion (AD). As a sustainable energy source with minimal use of hydrocarbons and a high energy yield, it is a promising alternative to fossil fuels. The utilization of a specialized pretreatment technique, in conjunction with the combination of fallen Trees leaves (FL) as a carbon-rich source and SS as a substrate with high nitrogen content, demonstrates significant potential for optimizing the microbial degradation process and maximizing biohydrogen production from SS combined with FL. Four treatment conditions for the SS were used in the present experiments: control phase (CP), thermal pretreatment phase (TP), co-fermentation phase with 0.25 g of volatile solids (VS) of FL/1.0 g SS (TPFL-1), and 0.5 g of VS of FL/1.0 g SS (TPFL-2). The results proved that the hydrogen production from TP exceeds that of CP by a factor of 232. When mixing FL with SS, it can lead to efficient biohydrogen production. According to our results, the optimum mixing ratio of SS to FL was 0.5 g VS of FL/1.0 g SS, and by this ratio, biohydrogen production was higher than the other ratio by 20%. The removal of COD and VS has increased by 27% and 21%, respectively, compared to other ratios. Concisely, the deployment of the prepared FL with SS led to improved biohydrogen production and enhanced sludge treatment efficiency.