Machines · FRD series
Rotary Vacuum Drum Filter
Continuous dewatering of industrial slurries at 2 to 40 wt% solids. A cloth-covered drum divided into compartments rotates through a stirred vat; an automatic valve applies vacuum to each compartment in turn, so that cake pick-up, dewatering, washing and discharge happen simultaneously at different points on the drum.
How it works
- The drum face is divided into circumferential compartments, each piped through the trunnion to one port of the automatic valve.
- Over the submerged arc the valve connects the compartment to form vacuum. Filtrate is drawn through the cloth and cake builds on the face.
- As the compartment leaves the vat the valve holds it on drying vacuum; entrained liquor is displaced and cake moisture falls.
- An optional wash arc applies displacement wash before the cake reaches the discharge point.
- At discharge the valve cuts vacuum and applies a snap blow of air, releasing the cake to a scraper, belt, string or roll take-off.
| Parameter | Value |
|---|---|
| Filtration area | 2.6 – 82 m² standard; larger to enquiry |
| Drum speed | 0.2 – 3 rpm standard, VFD; to 6 rpm on fast-filtering duty |
| Submergence | 30 – 35 % standard vat; 40 – 60 % high-submergence vat |
| Operating vacuum | 400 – 650 mmHg (53 – 87 kPa) below atmosphere |
| Feed solids | 2 – 40 wt% |
| Cake thickness | 3 – 40 mm, duty dependent |
| Cake discharge | Scraper (knife) · belt · string · roll · precoat |
| Drive | Helical-bevel geared motor, 415 V 3-ph 50 Hz, VFD controlled |
| Agitator | Oscillating rake, variable stroke, independent drive |
Size and selection
Standard build sizes. Filtration areas are calculated from the geometry, not nominal — a FRD-3x3 is exactly what the arithmetic says it is. Intermediate and larger sizes are built to duty.
| Model | Drum Ø (ft) | Face (ft) | Drum Ø (mm) | Face (mm) | Area (m²) | Drum drive (kW) | Agitator (kW) | Dry wt (t) |
|---|---|---|---|---|---|---|---|---|
| FRD-3x3 | 3 | 3 | 914 | 914 | 2.6 | 1.0 | 1.0 | 1.6 |
| FRD-4x4 | 4 | 4 | 1219 | 1219 | 4.7 | 1.5 | 1.0 | 2.3 |
| FRD-6x6 | 6 | 6 | 1829 | 1829 | 10.5 | 3.0 | 1.0 | 4.2 |
| FRD-8x8 | 8 | 8 | 2438 | 2438 | 18.7 | 4.0 | 1.5 | 7.1 |
| FRD-8x12 | 8 | 12 | 2438 | 3658 | 28.0 | 5.0 | 2.0 | 10.4 |
| FRD-10x10 | 10 | 10 | 3048 | 3048 | 29.2 | 5.5 | 2.0 | 10.8 |
| FRD-10x14 | 10 | 14 | 3048 | 4267 | 40.9 | 6.5 | 2.5 | 15.1 |
| FRD-12x12 | 12 | 12 | 3658 | 3658 | 42.0 | 7.0 | 2.5 | 15.5 |
| FRD-12x16 | 12 | 16 | 3658 | 4877 | 56.0 | 8.0 | 2.5 | 20.7 |
| FRD-12x20 | 12 | 20 | 3658 | 6096 | 70.0 | 9.5 | 3.0 | 25.9 |
| FRD-14x20 | 14 | 20 | 4267 | 6096 | 81.7 | 10.5 | 3.5 | 30.3 |
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 |
|---|---|
| Drum shell and heads | IS 2062 mild steel · MS rubber lined · SS 304 · SS 316 / 316L |
| Drum segments | SS 304 · SS 316L · polypropylene |
| Drainage grid | Polypropylene · SS 304 |
| Vat | Mild steel · MS rubber lined · SS 316L · FRP |
| Agitator | SS 304 · SS 316L · rubber lined MS |
| Automatic valve | Cast iron body with SS wear plate and UHMWPE bridge blocks |
| Scraper blade | UHMWPE · PTFE-faced |
| Trunnion liner | Cast iron · leaded bronze |
| Filter media | Polyester · polypropylene monofilament / multifilament |
| Caulking | PP rope · SS wire with PVC core |
Scope of supply
- Drum assembly — shell, heads, trunnions, segments, drainage grids, caulked filter cloth
- Vat with oscillating agitator and independent drive
- Automatic filter valve with wear plate, bridge blocks and timing adjustment
- Drum drive — helical-bevel geared motor with VFD, girth gear and pinion
- Cake discharge assembly to the selected method
- Cake wash header with spray nozzles (where specified)
- Filtrate receiver and moisture trap with sight glass and level switch
- Interconnecting vacuum and filtrate piping within the equipment envelope
- Structural supports, platform, walkway and handrail
- Local control panel with VFD, ammeter and interlocks
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 |
|---|---|
| High-submergence vat | Raises submergence to 60 % for high-capacity, fast-filtering duties |
| Precoat arrangement | Precoat tank, advancing knife with micrometer feed for polishing duties |
| Multi-stage cake wash | Two to four counter-current wash arcs with independent receivers |
| Cloth wash | High-pressure oscillating spray, both faces, with timer |
| Steam hood | Insulated hood for hot filtration and reduced cake moisture |
| Rubber lining | Full MSRL on drum, vat and agitator for chloride and acid service |
| Vacuum package | Liquid ring pump, separator and seal water system, skid mounted |
| Filtrate pump | Self-priming or barometric leg arrangement |
| PLC / HMI | Automatic valve timing, cake thickness trending, remote enable |
Applications
- Chemical — sodium sulphate, gypsum, soda ash, pigments, calcium carbonate
- Mineral processing — concentrate dewatering, tailings, clay
- Pulp and paper — brown stock washing, lime mud
- Pharmaceutical and food — starch, corn steep, crystalline intermediates
- Effluent — biological sludge, neutralisation sludge, recovery duties
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
Rotary Vacuum Drum Filter datasheetPDF · 3 pages · A4
Filcare product cataloguePDF · 16 pages · A4
Capability sheetPDF · 1 page · A4
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.