Table 2. Influence C/N ratio on ultimate biodegradability and volatile solids removal during anaerobic digestion at 18 d
Carbon type | C/N ratio | Ultimate biodegradability (%) | Volatile solid removal (%) | Biodegradable volatile solids removal (%) |
Starch | 10 | 100.0 | 82.7 | 82.7 |
25 | 99.2 | 86.4 | 87.1 |
40 | 99.5 | 89.3 | 89.8 |
Cellulose | 10 | 99.5 | 88.3 | 88.3 |
25 | 99.5 | 91.9 | 92.3 |
40 | 99.5 | 95.4 | 95.9 |
Xylan | 10 | 93.7 | 79.3 | 84.7 |
25 | 99.7 | 84.1 | 84.3 |
40 | 99.9 | 85.5 | 85.6 |
SEM | | 0.44 | 1.19 | 1.11 |
p-value1) | C | 0.001 | <0.001 | <0.001 |
CN | <0.001 | <0.001 | <0.001 |
C × CN | <0.001 | 0.935 | 0.048 |
C, effect of carbon type; CN, effect of carbon: nitrogen ratio; C × CN, interaction between carbon type and carbon: nitrogen ratio.
C/N ratio, carbon to nitrogen ratio; SEM, standard error of means.