Multimedia filters are a critical pre-treatment stage in industrial water treatment systems. Proper operation and maintenance ensure consistent filtrate quality, protect downstream equipment, and extend filter media lifespan.
1
Understanding Multimedia Filter Layers
- Anthracite (top layer — coarse, low density)
- Sand (middle layer — medium density)
- แมงกานีสไดออกไซด์ (สารกรองชนิดเร่งปฏิกิริยาสำหรับกำจัดเหล็กและแมงกานีส)
- Support gravel (base layer)
2
Backwashing Procedure
- Backwash flow rate (typically 12–15 gpm/ft²)
- Backwash duration (10–15 minutes)
- Air scouring (if applicable)
- Fast rinse cycle (5–10 minutes)
- Service return to filtration mode
3
Common Operational Issues
- Pressure drop increase
- Channeling through media bed
- Mudball formation
- Media loss during backwash
- Incomplete dirt removal
4
Maintenance Schedule
- Daily: inspect pressure differential
- Weekly: backwash cycle optimization
- Monthly: media bed inspection
- Annually: media replacement assessment
Engineering Note
Backwash flow rate is critical for multimedia filter performance. Too low — the bed won't fluidize and dirt remains. Too high — media is washed out. Always verify the bed expansion rate (typically 20–30%) during backwash using the sight glass.
Summary
Key practices for multimedia filter operation and maintenance:
- Understand the multimedia layer structure
- Follow proper backwashing procedures
- Monitor and address common operational issues
- Adhere to a regular maintenance schedule
Proper operation and timely maintenance of multimedia filters ensure consistent water quality, protect downstream equipment, and reduce long-term operating costs.
