Rotary Vacuum Disc Filter
Where the duty is high tonnage and cake washing is not critical, a disc filter gives three to four times the filtration area of a drum filter on the same footprint. Sectors bolt to a central barrel; each disc filters on both faces, and area is added simply by adding discs.
How it works
- Sectors are bolted radially to a hollow centre barrel, forming discs that rotate through a common vat.
- Each sector is piped through the barrel to the automatic valve, so the filtration cycle repeats once per revolution on both faces.
- Cake forms over the submerged arc, dewaters over the exposed arc and is released by snap blow to scrapers positioned between the discs.
- Because both faces filter, area per metre of machine length is very high — the reason the type dominates iron ore and pulp thickening duties.
| Parameter | Value |
|---|---|
| Filtration area | 9 – 429 m² depending on disc size and count |
| Discs per machine | 2 – 12 standard |
| Disc speed | 0.3 – 2.5 rpm, VFD |
| Submergence | 30 – 38 % |
| Operating vacuum | 400 – 600 mmHg (53 – 80 kPa) |
| Feed solids | 10 – 60 wt% |
| Cake thickness | 6 – 25 mm per face |
| Discharge | Snap blow with scraper blades between discs |
Size and selection
Standard build sizes. Filtration areas are calculated from the geometry, not nominal — a small is exactly what the arithmetic says it is. Intermediate and larger sizes are built to duty.
| Disc Ø (ft) | Disc Ø (m) | Hub Ø (m) | Area / disc (m²) | 2 discs (m²) | Max discs | Max area (m²) |
|---|---|---|---|---|---|---|
| 6 | 1.83 | 0.61 | 4.68 | 9.4 | 12 | 56.1 |
| 8 | 2.44 | 0.81 | 8.32 | 16.6 | 12 | 99.9 |
| 10 | 3.05 | 1.02 | 12.98 | 26.0 | 12 | 155.7 |
| 12 | 3.66 | 1.22 | 18.7 | 37.4 | 12 | 224.4 |
| 14 | 4.27 | 1.42 | 25.47 | 50.9 | 10 | 254.7 |
| 18 | 5.49 | 1.68 | 42.91 | 85.8 | 10 | 429.1 |
The area you need comes from a test, not from this table. Send the slurry, the throughput, the target cake moisture and any wash requirement, and we will size the machine against a leaf or pilot test so that the offer carries a guaranteed duty. Try the sizing calculator →
Materials of construction
| Parameter | Value |
|---|---|
| Sectors | Polypropylene · SS 316L · rubber lined MS |
| Centre barrel | Mild steel rubber lined · SS 316L |
| Vat | Mild steel rubber lined · SS 316L |
| Agitator | Oscillating rake, MSRL or SS |
| Automatic valve | Cast iron with SS wear plate, UHMWPE bridge blocks |
| Scraper blades | UHMWPE |
| Filter media | Sector bags — polyester / polypropylene monofilament |
Scope of supply
- Centre barrel with sectors and sector bags
- Vat with oscillating agitator and drive
- Automatic filter valve with wear plate and bridge blocks
- Main drive — helical-bevel geared motor with VFD
- Scraper assemblies and cake chutes between discs
- Snap blow air header with timing valve
- Filtrate receiver, moisture trap and barometric leg or pump
- Structural supports, walkway and handrail
- Local control panel
Not included as standard
- Civil foundation, grouting, anchor bolts and civil works
- Erection, alignment and commissioning supervision unless separately quoted
- Slurry feed pump, vacuum pump and filtrate pump unless listed in scope
- Power, air, water and effluent lines up to the equipment terminal points
- Instrumentation beyond the items listed in scope of supply
- Any statutory approvals, insurance or third-party inspection charges
Options
| Option | What it does |
|---|---|
| Sector quick-release | Wedge clamping for bag change without draining the vat |
| Cloth wash | Oscillating high-pressure spray between discs |
| Rubber lining | Full MSRL for chloride, acid and abrasive duty |
| Vacuum package | Liquid ring pump and separator, skid mounted |
| PLC / HMI | Valve timing, disc speed and vacuum trending |
Applications
- Iron ore and base metal concentrate dewatering
- Pulp thickening and stock washing
- Coal fines and flotation concentrate
- Kaolin, calcium carbonate and industrial minerals
Utilities at battery limit
| Parameter | Value |
|---|---|
| Power | 415 V ± 10 %, 3-phase, 50 Hz, 4-wire |
| Control supply | 240 V AC 1-phase / 24 V DC |
| Instrument air | 6 bar (g), oil-free, dew point −20 °C |
| Vacuum | By Filcare-supplied pump or client system, at battery limit |
| Wash water | Client supply at 3 bar (g), free of suspended solids > 200 µm |
Inspection and test
- Material test certificates (EN 10204 3.1) for all pressure-retaining and wetted plate
- Dye-penetrant examination of wetted welds
- Hydrostatic / leak test of vat, drum and filtrate lines
- Dimensional inspection against approved GA drawing
- No-load trial run at works: rotation, valve timing, agitator sweep
- Drive and gearbox test certificates from the OEM
Painting and finish
Surface preparation to SA 2½, two coats epoxy primer (2 × 40 µm DFT) and two coats epoxy finish (2 × 50 µm DFT). Stainless steel parts supplied pickled and passivated, unpainted.
Downloads
Certified data is issued with the approved general-arrangement drawing.
Send us the slurry. We will send you the machine.
Slurry description · solids wt % · throughput · target cake moisture · wash requirement · temperature and pH. Offers are prepared by Mr. T. Srikanth.