Table 1.
Substrate analysis.
| Characteristic | Wheat straw (WS) | T1 | T2 | T3 | T4 |
|---|---|---|---|---|---|
| Moisture (%) | 61.45 (1.53) | 6.8 (0.23)ˆ* | 6.25 (0.27)ˆ* | 6.18 (0.16)ˆ* | 6.32 (0.34)ˆ* |
| N (%) | 1.16 (0.02) | 1.48 (0.02) | 2.23 (0.04) | 2.75 (0.12) | 2.13 (0.05) |
| P (%) | 0.35 (0.14) | 0.23 (0.15) | 0.26 (0.21) | 0.37 (0.22) | 0.30 (0.12) |
| K (%) | 0.20 (0.13) | 0.38 (0.12) | 0.49 (0.15) | 0.56 (0.14) | 0.51 (0.13) |
| Fe (ppm) | 315.10 (0.12) | 75.23 (0.13) | 446.50 (0.07) | 465.45 (0.15) | 525.37 (0.04) |
| Zn (ppm) | 120.25 (0.15) | 121.30 (0.05) | 145.50 (0.12) | 130.45 (0.05) | 162.50 (0.03) |
| Celluloses (%) | 34.23 (1.14) | 18.15 (1.14) | 14.35 (0.75) | 12.85 (0.46) | 12.65 (0.77) |
| Hemicelluloses (%) | 26.18 (2.31) | 20.86 (0.73) | 14.20 (0.82) | 13.58 (0.65) | 10.82 (0.56) |
| Lignin (%) | 17.5 (0.32) | 7.42 (0.52) | 5.75 (0.95) | 5.62 (0.74) | 4.75 (0.69) |
| Saponins (%) | 0.0 | 0.0 | 2.92 (0.78) | 1.32 (0.85) | 2.26 (0.54) |
| C/N ratio | 34.22 | 18.2 | 12.44 | 12.21 | 12.50 |
| pH | 6.68 (0.02) | 7.46 (0.02) | 7.38 (0.02) | 7.32 (0.02) | 7.35 (0.02) |
∗Values are indicated for dried biogas slurries. Numbers in brackets indicate standard deviation. T1 = Biogas slurry (BGS) of CD; T2 = BGS of 50 (CW DMC):50 (CD); T3 = BGS of 50 (HW DMC):50 (CD); T4 = BGS of 75 (HW DMC):25 (CD)