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 |
CD 01–04 co-digestion plants, WWTP 01–06 wastewater treatment plants
aTotal solids
bVolatile solids
cHydraulic retention time
dTemperature
eTotal nitrogen
fVolatile fatty acids
gOrganic loading rate
hTotal ammonium nitrogen
iFree ammonia, calculated according to Hansen et al. [106]
jSource-separated municipal organic waste