Advanced Bioconversion of sugary wastewater: Integrated polyhydroxybutyrate and hydrogen productions in a continuous airlift two-chamber bioreactor
Journal
International Journal of Hydrogen Energy
ISSN
0360-3199
Date Issued
2024-09-24
Author(s)
DOI
10.1016/j.ijhydene.2024.09.293
Abstract
This study utilized a novel Continuous Airlift Two-chamber Bioreactor (CATBR) for the co-production of hydrogen and polyhydroxybutyrate (PHB) from mixed microbial cultures in sugary wastewater. Hydrogen generation was investigated in a defined bacterial consortium that contained mainly Clostridium species, and diverse microbial communities were studied in relation to PHB production, demonstrating the ability of diverse microbial communities to form stable microbial consortia. The impact of hydraulic retention time (HRT), pH, and air flow rate on PHB production was evaluated with special emphasis on volatile suspended solids (VSS). Optimal conditions for hydrogen and PHB production were established at a pH of 5.5, an aeration rate of 1500 mL/h, and an HRT of two days. Hydrogen yield was determined to be 3.14 ± 0.92 mL/g COD, and PHB yield was 31.32% (g PHB/g VSS). Production rates for hydrogen and PHB peaked at 0.23 ± 0.07 L/L.d and 0.64 g PHB/L.d, respectively, with a COD removal efficiency of 85 ± 0.67%. At an HRT of two days, the PHB generation rate was found to be 6–10 times higher than previously reported rates. The application of immobilized cell technology effectively prevented bacterial washout from the reactor, thereby ensuring stable operational conditions.
Subjects
Two-chamber bioreactor
Biohydrogen
Polyhydroxybutyrate
Hydraulic retention time
Airflow rate
Volatile fatty acids
Publisher
Elsevier BV
Type
journal article