Sub Bituminous Coal Blended Analysis
Table 3:
| Index Factors | Factor | Low | Medium | High |
| (1) Slagging Index | ||||
| Base / acid ratio (B/A Ratio) | (Fe₂O₃+CaO+MgO+Na₂O+K₂O) wt.% / (SiO₂+AI₂O₃+TiO₂)wt.% | <0.3 | 0.3-0.6 | >0.6 |
| Slagging factor | (Base / Acid) x Total sulfur | <2.0 | 2.0-2.9 | >2.9 |
| Iron Content | Fe₂O₃ wt % | <10 | 10-25 | >25 |
| (2) Fouling Index | ||||
| Sodium content | Na₂O (wt.%) | <2.0 | 2.0-5.0 | >5.0 |
| Fouling factor | (Base / Acid) x Na₂O (wt.%) | <0.5 | 0.5-1.25 | >1.25 |
| Alkaline metal content | Na₂O + K₂O (wt.%) | <3.0 | 3.0-6.0 | >6.0 |