Table 1 Operating data for the 10 industrial-scale biogas plants investigated in this study
Digester code | TSa (%) | VSb (%) | HRTc (day) | TMd (°C) | Tot Ne (g L−1 ww) | pH | VFAf (g L−1) | OLRg (vs g L−1 day−1) | TANh (g L−1 ww) | Ammoniai (g L−1 ww) | Major substrate |
|---|---|---|---|---|---|---|---|---|---|---|---|
CD01 | 5.7 | 3.5 | 45 | 38 | 8.7 | 7.8 | 1.3 | 3.0 | 4.6 | 0.365 | SSMOWj, slaughterhouse waste |
CD02 | 4.8 | 3.8 | 55 | 38 | 9.1 | 7.8 | 0.8 | 2.9 | 5.1 | 0.408 | Thin stillage |
CD03 | 2.6 | 2.0 | 30 | 37 | 2.6 | 7.3 | <0.1 | 3.0 | 0.9 | 0.022 | SSMOW |
CD04 | 7.1 | 1.3 | 70 | 38 | 6.2 | 7.7 | 3.0 | 3.0 | 3.5 | 0.218 | Grass, wheat-based stillage |
WWTP01 | 2.7 | 1.9 | 17 | 38 | 2.5 | 7.3 | <0.1 | 2.4 | 1.4 | 0.036 | Mixed sludge |
WWTP02 | 3.5 | 2.5 | 23 | 37 | 2.9 | 7.5 | 0.2 | 3.1 | 1.6 | 0.063 | Mixed sludge |
WWTP03 | 2.4 | 1.9 | 18 | 38 | 1.8 | 7.3 | 0.1 | 2.0 | 0.9 | 0.022 | Mixed sludge |
WWTP04 | 3.4 | 2.4 | 30 | 37 | 2.9 | 7.5 | 0.3 | 1.6 | 1.5 | 0.058 | Mixed sludge |
WWTP05 | 2.5 | 2.1 | 22 | 37 | 2.1 | 7.3 | 0.1 | 2.8 | 1.1 | 0.027 | Mixed sludge |
WWTP06 | 2.1 | 5.5 | 26 | 34 | 1.8 | 7.3 | <0.1 | 1.1 | 1.1 | 0.023 | Mixed sludge |