Performance evaluation of an innovative hybrid dark fermentation–microbial electrolysis cell system for biohydrogen production and sludge dewaterability improvement using primary and waste activated sludge
Journal of Behdasht dar Arseh (i.e., Health in the Field),
Vol. 13 No. 3 (1404),
10 June 2026
,
Page 3-18
https://doi.org/10.22037/jhf.v13i3.51063
Abstract
Background and Aims: Biohydrogen production from sewage sludge serves as a dual solution for sustainable energy supply and effective waste management. This study aims to investigate the feasibility of a combined Dark Fermentation (DF) and Microbial Electrolysis Cell (MEC) system to enhance hydrogen yield while simultaneously improving the dewaterability of municipal sewage sludge.
Materials and Methods: Primary and waste activated sludge (WAS) samples were collected from units 1 to 4 of the South Tehran Wastewater Treatment Plant and underwent thermal pretreatment. The samples waz then introduced into single-stage systems of Dark Fermentation (DF) and a combined Dark Fermentation-Microbial Electrolysis Cell (DF-MEC). Biohydrogen yield and sludge dewaterability were evaluated based on parameters including pH, Volatile Fatty Acids (VFAs), hydrogen production yield, Specific Resistance to Filtration (SRF), Capillary Suction Time (CST), and the structural characteristics of Extracellular Polymeric Substances (EPS). This research was conducted in full compliance with all ethical principles and considerations throughout all stages.
Results: The integrated system significantly increased the biohydrogen yield at pH 6 compared to the Dark Fermentation (DF) process. The hydrogen yields for primary sludge and waste activated sludge (WAS) reached 38.13 and 19.66 mLH2/gVS, respectively. Furthermore, this system facilitated sludge disintegration and the release of bound water, leading to a substantial enhancement in the dewaterability of the effluent sludge.
Conclusion: The application of the integrated system combined with thermal pretreatment increases biohydrogen production yield while improving the performance of the municipal sewage sludge dewatering process, and can be proposed as an efficient solution for optimal sludge management and clean energy supply.
- Sludge treatment
- Dark fermentation
- Microbial electrolysis cell
- Biohydrogen production
- Dewaterability
How to Cite
References
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