1. Short hydraulic retention time in methane production from sewage sludge hydrolysate using anaerobic moving-bed biofilm reactors (AnMBBR) under thermophilic and mesophilic conditions.
- Author
-
Niero, Luisa, Morgan-Sagastume, Fernando, Pelkonen, Markku, and Lagerkvist, Anders
- Subjects
SEWAGE sludge ,RF values (Chromatography) ,ANAEROBIC digestion ,BIOGAS ,ANAEROBIC microorganisms ,BIOGAS production - Abstract
The use of anaerobic moving-bed biofilm reactors was investigated for biogas production from the liquid fraction of sewage sludge hydrolysate. Anaerobic digestion requires traditionally long retention times due to the slow growth of methanogens. This work investigated biogas production with 2–3 days retention time under mesophilic (37°C) and thermophilic (50°C) conditions. Two continuous reactors were operated to treat the liquid fraction of hydrolysate sewage sludge for 196 days. The mesophilic reactor showed a more stable performance compared to the thermophilic one. The mesophilic reactor kept the soluble COD removal above 80 % at a volumetric loading rate (VLR) above 7 g COD L
−1 d−1 , and specific surface loading rate (SARL) above 20 g SCOD m−2 d−1 . In contrast, the thermophilic reactor displayed a soluble COD removal above 80 % at an average VLR of 4.2 g COD L-1 d-1, and average SARL of 14 g SCOD m−2 d−1 . The biogas from both systems contained 73 % methane. The microbial analysis of the biofilm showed that 36 % of the viable cells were anaerobic microorganisms. [Display omitted] • Biogas is produced from hydrolyzed sewages sludge in less than 3-day retention time. • Biogas has high methane content, above 70 %. • Mesophilic anaerobic MBBR was found more stable than thermophilic one. • The removal of the soluble COD was 80 % at a volumetric organic load above 7 g COD L−1 d−1 . [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF