| Byproduct | Composition | |||
| Nitrogen | Phosphorus | Potassium | pH | |
| mg∙kg−1 | mg∙g−1 | mg∙kg−1 | ||
| Red mud iron filter cake | <1.0 | 33.9 | <100.0 | 7.0 |
| Water treatment residual | 7700 | 1.2 | 1400 | 7.0 |