Garnet
Garnet is a mineral filter medium with high density and hardness. It retains solid particles in the spaces between its grains, providing physical filtration.
Fine and coarse grades serve different purposes. Fine garnet can form the lower filtration layer in a multimedia bed, while coarser grades can provide a support layer in suitable arrangements.
Technical Specifications
| Mineral type | Garnet |
|---|---|
| Grain grade | Fine filtration grade |
| Crystal structure | Cubic |
| Effective particle size | 0.34 mm |
| Bulk density | 2,080 kg/m³ |
| Uniformity coefficient | 1.33 |
| Particle density | 3.87–4.13 g/cm³ |
Application and use
- Fine garnet provides the final solids-retention layer beneath sand in downflow multimedia filters.
- In industrial water and wastewater filtration, it complements coarser upper layers that capture larger particles.
- Coarse garnet can support other dense media; support grades and fine filtration grades are selected separately.
- Backwash design must restore the intended layer arrangement without carrying media out of the vessel.
Frequently asked questions
Where does garnet sit in an existing multimedia filter?
A fine filtration grade generally sits below lighter, coarser layers. Review the complete existing bed.
Are fine garnet and support garnet the same product?
No. Fine filtration and coarse support grades have different particle distributions and duties; confirm the supplied grade.
Can waterjet garnet be used for filtration?
A waterjet designation does not establish water-treatment suitability. Check the water-filtration grade and use documentation.
What micron size does garnet retain?
A reliable micron rating cannot be inferred from garnet grain size alone. Assess the whole bed, incoming water and operating conditions.
Is the existing backwash system suitable?
Compare the chosen garnet's density and grading with backwash flow and available bed-expansion space.