Sample | pH | Acetate (mg/kg) | Butyrate (mg/kg) | Total acidity (mg acetic acid eq/kg) | N-NH4+ (mg/kg) | FOS/TAC | CH4 (%) | CH4 yield (Nm3/t VS) |
---|---|---|---|---|---|---|---|---|
Inoculum | 7.90 ± 0.02 | 123 ± 17 | 87 ± 3 | 175 ± 30 | 1833 ± 18 | 0.22 ± 0.02 | 60.4 ± 0.4b | 67.0 ± 0.9b |
Reactor start-up (days 0–9) | 7.70 ± 0.02 | 89 ± 6 | 0a | 89 ± 6 | 1740 ± 17 | 0.24 ± 0.02 | 55.9 ± 3.2 | 329. 2 ± 19.8 |
Reactor steady-state (days 10–74) | 7.70 ± 0.05 | 82 ± 5 | 0a | 82 ± 5 | 1715 ± 1 | 0.25 ± 0.02 | 53.7 ± 0.3 | 339.3 ± 1.4 |