| Component (Vol%) | Flue gas | Synthetic gas |
| N2 | 75 - 80 | 70 - 90 |
| CO2 | 10 - 20 | 30 - 10 |
| O2 | 5 - 9 | - |
| SO2 | 0.02 - 0.54 | 0.7 - 0.9 |
| NOx | 0.02 - 0.53 | 0.7 - 0.9 |