What are vacuum belt filters used for?
A vacuum belt filter continuously separates slurry into cake and filtrate on a moving filter medium. It can suit tested mineral-processing duties that benefit from continuous operation and staged cake washing.
How it works
Vacuum draws liquid through the cake and cloth as they travel over a drainage arrangement. Feed distribution, cake thickness, vacuum conditions and cloth cleaning influence filtration. Washing zones may be incorporated where product chemistry requires them.
When to consider it
Consider a horizontal vacuum belt filter when testwork supports adequate filtration and the process needs continuous throughput or cake washing. Define the required moisture, filtrate quality and any wash-removal target.
Application limits to check
The available pressure difference is constrained by vacuum conditions. Very fine or difficult-to-filter slurry may need another technology. Air leakage, cloth blinding and unsuitable feed distribution can undermine performance.
Selection data for a useful quotation
These are enquiry inputs, not specifications of a single model. Include measured values, units and the expected operating range; flag anything still to be tested.
| Input | What to provide |
|---|---|
| Feed | Solids rate, particle-size distribution, density and chemistry |
| Testwork | Vacuum filtration rate, cake moisture and cloth response |
| Cake washing | Contaminant target, wash ratio and filtrate separation |
| Machine duty | Active area, belt speed and cake thickness assumptions |
| Utilities | Vacuum supply, seals, wash water, compressed air if needed |
| Layout | Drainage, belt tracking, cloth access and cake discharge |
Compare the complete duty
Compare with a filter press at the same feed and cake requirements. Continuous operation and washing may favor a belt filter, while a pressure-filtration duty may favor another arrangement. Testwork resolves the tradeoff.
Before accepting a supplier proposal
- Review filtration and washing tests with the proposed cloth.
- Confirm vacuum equipment, filtrate receivers and separate liquid streams.
- Check belt tracking, sealing, cleaning and replacement access.
Buyer questions about vacuum belt filters
Can a vacuum belt filter wash the cake?
Many designs allow washing zones, but their effectiveness depends on cake structure and process conditions. Include washing tests in the enquiry.
Does continuous operation guarantee a lower moisture cake?
No. Moisture depends on material, cake thickness, vacuum and available filtration time.
Is the vacuum pump always part of supply?
Not necessarily. Ask for a complete equipment list that includes vacuum, filtrate, wash and control systems.
Technical reference
Metso: official equipment and technology description ↗
The source provides technology context. The selection checklist is KMS Industrial editorial guidance; manufacturer models and performance figures are not KMS specifications.