Table 5 Analysis data of the digestates and foams of biogas plant BP B
From: Foam formation in full-scale biogas plants processing biogenic waste
Digestate | Foam | Digestate | Digestate | Digestate | Foam | Digestate | ||
|---|---|---|---|---|---|---|---|---|
August 2011 | April 2012 | May 2012 | June 2012 | July 2012 | ||||
Index | Foaming | Foam-free | Foaming | Foaming | Foam-free | |||
TS [%] | O | 4.82 | 4.70 | 3.87 | 4.87 | n. d. | n. d. | 4.68 |
VS [% TS] | O | 72.1 | 79.9 | 51.2 | 55.6 | 51.9 | 50.9 | 53.1 |
pH [−] | CE | 7.70 | 7.50 | 8.20 | 7.87 | 8.06 | 8.02 | 7.89 |
VFA/TIC [−] | CA | 0.19 | 0.24 | 0.14 | 0.18 | 0.16 | 0.17 | 0.20 |
NH4-N [g/L] | F, S | 1.38 (F) | 1.89 (F) | 1.58 (S) | 2.55 (S) | n. d. | n. d. | 3.95 (F) |
Total organic carbon [g/L] | B | 11.1 | 13.7 | 17.0 | 20.6 | 12.8 | 8.62 | 14.0 |
Total nitrogen [g/L] | B | 3.77 | 2.36 | 5.43 | 8.81 | 5.86 | 5.12 | 6.36 |
Crude protein [g/L] | CA | 14.9 | 2.83 | 24.0 | 39.1 | n. d. | n. d. | 15.0 |
Acetic acid [mg/L] | F | 583 | 564 | 16.9 | 601 | 446 | 71.0 | 1,061 |
Propionic acid [mg/L] | F | 63.5 | 162 | 0 | 81 | 17.6 | 0 | 125.9 |
Butyric acid [mg/L] | F | 0 | 39.6 | 0 | 0 | 0 | 0 | 13.8 |
Calcium [mg/L] | F | 85.2 | 38.8 | 97.1 | 119 | 67 | 31.6 | 158 |
Iron [mg/L] | F | 4.42 | 4.69 | 14.1 | 4.44 | 5.82 | 5.02 | 6.00 |
Magnesium [mg/L] | F | 10.1 | 7.02 | 15.8 | 34.2 | 11.7 | 29.0 | 39 |
Nickel [mg/L] | F | <2 | <2 | 8.71 | <0.8 | <0.8 | <0.8 | 2.4 |
Phosphorus [mg/L] | F | 12.8 | 19.7 | 70.4 | 68.8 | 38.4 | 6.92 | 47.4 |
Potassium [mg/L] | F | 1,700 | 1,190 | 1,602 | 1,606 | 1,500 | 1,546 | 1,762 |
Sulfur [mg/L] | F | 30.8 | 28.2 | 59.2 | 62.2 | 33.8 | 33.6 | 38.6 |