Hythane (H2 + CH4) production from petrochemical wastewater containing mono-ethylene glycol (MEG) via a novel stepped anaerobic baffled (SAB) reactor was investigated. The reactor was continuously operated for five months at constant hydraulic retention time (HRT) of 72 h and different organic loading rates (OLRs) of 0.33, 0.67 and 1.67 gCOD l-1 d-1. The maximum H2 yield of 359.01 ± 33.46 ml H2 gCODremoved-1 and H2 production rate of 5.12 ± 0.48 l d-1 were obtained at OLR of 1.67 gCOD l-1 d-1. Nevertheless, the maximum methane yield of 159.11 ± 14.72 ml CH4 gCODremoved-1 and methane production rate of 2.48 ± 0.22 l d-1 were recorded at OLR of 0.67 gCOD l-1 d-1. The maximum CH4 and H2 content of 52.08 and 49.84% were achieved at OLR of 0.33 and 1.67 gCOD l-1 d-1, respectively. Compartment-wise hythane profiles were assessed to optimize the production rate. Microbial community analysis was conducted and showed the dominant bacteria of Proteobacteria (44.3%), Firmicutes (28.9%), Chloroflexi (8.9%), Actinobacteria (5.7%), and Bacteroidetes (5.6%).
- Microbial community
- Mono-ethylene glycol
- Organic loading rate
- Petrochemical wastewater
- Stepped anaerobic baffled reactor