Table 2.
Physicochemical parameters for distinct composting treatments using distinct raw materials (data collected at 1, 20, 40, 60, 80, 100 and 120 days; n = 70)
| Parameter | Treatments* | Total | ||||
|---|---|---|---|---|---|---|
| T1 | T2 | T3 | T4 | T5 | ||
| Humidity (%) | 42.7 ± 3.8a | 25.5 ± 2.5bc | 24.4 ± 1.8bc | 22.5 ± 2.7c | 25.3 ± 1.2b | 28.1 ± 1.4 |
| pH | 8.3 ± 0.1a | 7.5 ± 0.1bc | 7.3 ± 0.1c | 7.4 ± 0.1bc | 7.6 ± 0.1b | 7.6 ± 0.1 |
| Electrical conductivity (mS/cm) | 1.8 ± 0.1c | 4.7 ± 0.2a | 4.6 ± 0.2a | 3.8 ± 0.1b | 4.4 ± 0.5a | 3.8 ± 0.1 |
| Total Kjedahl nitrogen (%) | 2.0 ± 0.1d | 7.2 ± 0.2b | 7.9 ± 0.2a | 7.2 ± 0.2b | 6.4 ± 0.2c | 6.1 ± 0.2 |
| C/N ratio | 20.4 ± 1.7a | 6.5 ± 0.4cd | 5.9 ± 0.3d | 6.5 ± 0.3bc | 7.3 ± 0.4b | 9.3 ± 0.7 |
| Phosphorus (%) | 2.0 ± 0.2c | 3.3 ± 0.1ab | 3.3 ± 0.1b | 3.1 ± 0.4b | 3.5 ± 0.1a | 3.0 ± 0.1 |
*T1 (control): sawdust and slaughterhouse sludge (50:50, v:v)
T2: sawdust, slaughterhouse sludge and meal from dead pigs (50:20:30)
T3: sawdust, slaughterhouse sludge and meal from dead pigs (50:10:40)
T4: sawdust, stabilizing compost and meal from dead pigs (50:20:30)
T5: sawdust, stabilizing compost and meal from dead pigs (50:30:20)
a,b,cMeans ± SEM with distinct superscripts differ in the lines across treatments (P < 0.05)