Summary of average performance data or average effluent concentrations for experimental and control CSADs during the entire operating period
| Parameter . | Form . | Units . | Experimental . | Control . | ||||
|---|---|---|---|---|---|---|---|---|
| Phase I . | Phase II . | Phase III . | Phase I . | Phase II . | Phase III . | |||
| Biogas production rate | – | L·d−1 | 11.99 ± 5.9a (n = 90) | 11.87 ± 5.4 (n = 14) | 10.21 ± 3 (n = 31) | 11.92 ± 6a (n = 90) | 11.59 ± 5.5 (n = 14) | 10.36 ± 3 (n = 31) |
| COD concentration | TCOD | g·L−1 | 17.93 ± 0.6 (n = 20) | 18.75 ± 0.5 (n = 4) | 20.04 ± 0.9 (n = 4) | 17.18 ± 0.62 (n = 20) | 18.77 ± 0.71 (n = 4) | 19.82 ± 0.41 (n = 4) |
| SCOD | mg·L−1 | 272.4 ± 13.7 (n = 21) | 256.9 ± 10.3 (n = 5) | 287.1 ± 12.2 (n = 5) | 269.9 ± 10.6 (n = 21) | 262.3 ± 9.8 (n = 5) | 257.9 ± 14.1 (n = 5) | |
| COD removal efficiency | TCOD | % | 58.9 ± 7.7 (n = 20) | 63.75 ± 2.9 (n = 4) | 68.10 ± 11.2 (n = 4) | 62.63 ± 8.7 (n = 20) | 62.12 ± 3.2 (n = 4) | 60.81 ± 16.7 (n = 4) |
| SCOD | % | 79.60 ± 9.5 (n = 21) | 86.80 ± 8.2 (n = 4) | 91.75 ± 1.2 (n = 4) | 79.70 ± 9.8 (n = 21) | 84.64 ± 8.5 (n = 4) | 91.02 ± 1.5 (n = 4) | |
| TVFA concentration | – | mg·L−1 | 55.2 | 70.6 | 51.2 | 45.2 | 54.05 | 55.2 |
| Ammonia concentration | N | mg·L−1 | 728.4 | 945.4 | 778.4 | 726.8 | 910.7 | 745.8 |
| Solids concentration | TS | g·L−1 | 18.42 ± 0.11 (n = 10) | 21.25 ± 0.14 (n = 4) | 18.23 ± 0.37 (n = 5) | 18.89 ± 0.69 (n = 10) | 22.03 ± 0.09 (n = 4) | 17.86 ± 0.11 (n = 5) |
| VS | g·L−1 | 10.68 ± 0.12 (n = 10) | 11.69 ± 0.12 (n = 4) | 9.68 ± 0.18 (n = 5) | 11.10 ± 0.62 (n = 10) | 12.26 ± 0.05 (n = 4) | 9.57 ± 0.09 (n = 5) | |
| Solids removal efficiency | TS | % % | 56.53 ± 5.4 (n = 10) | 57.54 ± 2.0 (n = 4) | 58.52 ± 6.4 (n = 5) | 59.12 ± 5.3 (n = 10) | 55.51 ± 2.3 (n = 4) | 53.23 ± 13.8 (n = 5) |
| VS | % | 61.05 ± 4.9 (n = 10) | 63.98 ± 3.0 (n = 4) | 61.84 ± 7.0 (n = 5) | 62.74 ± 4.8 (n = 10) | 60.52 ± 2.1 (n = 4) | 56.13 ± 15.7 (n = 5) | |
| Alkalinity | CaCO3 | mg·L−1 | 3,750 | 3,680 | 3,640 | 3,690 | 3,700 | 3,620 |
| pH | – | – | 7.09 ± 0.21 (n = 90) | 6.91 ± 0.12 (n = 14) | 6.92 ± 0.16 (n = 31) | 7.11 ± 0.17 (n = 90) | 6.93 ± 0.14 (n = 14) | 6.94 ± 0.15 (n = 31) |
| Parameter . | Form . | Units . | Experimental . | Control . | ||||
|---|---|---|---|---|---|---|---|---|
| Phase I . | Phase II . | Phase III . | Phase I . | Phase II . | Phase III . | |||
| Biogas production rate | – | L·d−1 | 11.99 ± 5.9a (n = 90) | 11.87 ± 5.4 (n = 14) | 10.21 ± 3 (n = 31) | 11.92 ± 6a (n = 90) | 11.59 ± 5.5 (n = 14) | 10.36 ± 3 (n = 31) |
| COD concentration | TCOD | g·L−1 | 17.93 ± 0.6 (n = 20) | 18.75 ± 0.5 (n = 4) | 20.04 ± 0.9 (n = 4) | 17.18 ± 0.62 (n = 20) | 18.77 ± 0.71 (n = 4) | 19.82 ± 0.41 (n = 4) |
| SCOD | mg·L−1 | 272.4 ± 13.7 (n = 21) | 256.9 ± 10.3 (n = 5) | 287.1 ± 12.2 (n = 5) | 269.9 ± 10.6 (n = 21) | 262.3 ± 9.8 (n = 5) | 257.9 ± 14.1 (n = 5) | |
| COD removal efficiency | TCOD | % | 58.9 ± 7.7 (n = 20) | 63.75 ± 2.9 (n = 4) | 68.10 ± 11.2 (n = 4) | 62.63 ± 8.7 (n = 20) | 62.12 ± 3.2 (n = 4) | 60.81 ± 16.7 (n = 4) |
| SCOD | % | 79.60 ± 9.5 (n = 21) | 86.80 ± 8.2 (n = 4) | 91.75 ± 1.2 (n = 4) | 79.70 ± 9.8 (n = 21) | 84.64 ± 8.5 (n = 4) | 91.02 ± 1.5 (n = 4) | |
| TVFA concentration | – | mg·L−1 | 55.2 | 70.6 | 51.2 | 45.2 | 54.05 | 55.2 |
| Ammonia concentration | N | mg·L−1 | 728.4 | 945.4 | 778.4 | 726.8 | 910.7 | 745.8 |
| Solids concentration | TS | g·L−1 | 18.42 ± 0.11 (n = 10) | 21.25 ± 0.14 (n = 4) | 18.23 ± 0.37 (n = 5) | 18.89 ± 0.69 (n = 10) | 22.03 ± 0.09 (n = 4) | 17.86 ± 0.11 (n = 5) |
| VS | g·L−1 | 10.68 ± 0.12 (n = 10) | 11.69 ± 0.12 (n = 4) | 9.68 ± 0.18 (n = 5) | 11.10 ± 0.62 (n = 10) | 12.26 ± 0.05 (n = 4) | 9.57 ± 0.09 (n = 5) | |
| Solids removal efficiency | TS | % % | 56.53 ± 5.4 (n = 10) | 57.54 ± 2.0 (n = 4) | 58.52 ± 6.4 (n = 5) | 59.12 ± 5.3 (n = 10) | 55.51 ± 2.3 (n = 4) | 53.23 ± 13.8 (n = 5) |
| VS | % | 61.05 ± 4.9 (n = 10) | 63.98 ± 3.0 (n = 4) | 61.84 ± 7.0 (n = 5) | 62.74 ± 4.8 (n = 10) | 60.52 ± 2.1 (n = 4) | 56.13 ± 15.7 (n = 5) | |
| Alkalinity | CaCO3 | mg·L−1 | 3,750 | 3,680 | 3,640 | 3,690 | 3,700 | 3,620 |
| pH | – | – | 7.09 ± 0.21 (n = 90) | 6.91 ± 0.12 (n = 14) | 6.92 ± 0.16 (n = 31) | 7.11 ± 0.17 (n = 90) | 6.93 ± 0.14 (n = 14) | 6.94 ± 0.15 (n = 31) |
aFirst 30 days excluded for both CSADs. In addition, a correction factor of 0.704 L·d−1 was subtracted from all the data through days 30–180 for only the experimental CSAD due to an experimental error in biogas production measurement. Error bars represent the standard deviation of the measurements.