By Senjie Filter Press Engineering Team · Last updated: 2026-09-14
Quick answer: A chamber filter press dewaters marble, granite and engineered stone cutting slurry from 10 to 30% solids to a 20 to 28% moisture cake in 20 to 40 minute cycles and returns 90 to 95% of the water to the saws. Most cutting shops use 800 to 1250 mm plates, abrasion-resistant monofilament cloth, and automatic plate shifting for unattended operation.
Every gang saw, wire saw, bridge saw and polishing line runs on cooling water that picks up stone fines at 20 to 100 g/L. Shops now recycle this water because discharge is restricted and fresh water costs money. This guide covers the recycling loop, sludge quantities, plate sizing, cloth life and cake reuse. Machine specifications are on the chamber filter press page.
How does a stone-cutting water recycling loop work?
A stone-cutting water loop collects slurry from the saws in a pit, dose-flocculates it into a vertical clarifier that settles fines to a 10 to 30% solids underflow, dewaters that underflow on a filter press to a 20 to 28% moisture cake, and returns clarified water at under 100 mg/L suspended solids to the saws, recovering 90 to 95% of the volume.
The loop has five parts: a collection pit with an agitator or submersible pump, a dosing station adding 0.05 to 0.2 kg of anionic polymer per tonne of solids, a cone-bottom clarifier of 3 to 6 m diameter, the filter press, and a clean-water pump back to the saws.
Water losses are cake moisture, evaporation and spray drift, together 5 to 10% of the circulating volume. A shop circulating 100 m³/h adds only 5 to 10 m³/h of make-up water, and cleaner water reduces diamond segment wear.
How much stone slurry does a cutting shop produce?
A stone shop turns 15 to 25% of processed block mass into fines: a gang saw with a 4 to 5 mm kerf on 2 cm slabs loses about 18% of the block, and polishing adds 2 to 4%, so a shop processing 50 t of block per day produces 8 to 12 t of dry fines per day.
Marble fines are calcium carbonate at 2.7 t/m³ and 5 to 20 µm. Granite fines are silica and feldspar at 2.6 to 2.7 t/m³, 10 to 40 µm, with 1 to 3% steel grit. Engineered quartz fines are finer and carry resin, which slows filtration.
At 25% cake moisture, 10 t of dry fines becomes 13.3 t of cake, or 7.5 to 8.5 m³ at a bulk density of 1.6 to 1.8 t/m³. This volume sets the plate count.
| Shop type | Block processed (t/day) | Dry fines (t/day) | Thickened slurry at 20% (m³/day) | Cake at 25% moisture (m³/day) |
|---|---|---|---|---|
| 1 bridge saw + 1 polisher | 5–15 | 1–3 | 4–13 | 0.8–2.4 |
| 1–2 gang saws + polishing line | 30–60 | 5–12 | 22–52 | 4–9 |
| Multi-wire saw line + polishing | 100–200 | 20–40 | 85–170 | 15–30 |
Which filter press size does a marble or granite shop need?
A shop producing 5 to 12 t of dry fines per day needs a 1000 to 1250 mm chamber press with 60 to 100 plates running 2 to 4 cycles per day; a single-saw shop with 1 to 3 t/day uses a 630 to 800 mm press with 20 to 40 plates, and a multi-wire line above 20 t/day uses one or two 1250 to 1500 mm presses with 100 to 150 plates.
Stone fines are granular and incompressible, so they filter fast: a chamber fills in 10 to 20 minutes at 0.6 to 0.8 MPa and the full cycle takes 20 to 40 minutes. A shop with automatic plate shifting can therefore choose a smaller press and run 15 to 25 cycles a day. Feed with a rubber-lined slurry pump above 20 m³/h or an air-operated diaphragm pump below it; progressing cavity pumps wear quickly on granite fines.
| Dry fines (t/day) | Plate size (mm) | Chamber volume per plate (m³) | Plates | Cycles per day | Recommended shifting |
|---|---|---|---|---|---|
| 1–3 | 630–800 | 0.007–0.013 | 20–40 | 3–6 | Manual or semi-automatic |
| 5–12 | 1000–1250 | 0.023–0.040 | 60–100 | 2–4 | Automatic |
| 20–40 | 1250–1500 | 0.040–0.060 | 100–150, or 2 units | 4–8 | Automatic with cloth washing |
A membrane press is rarely needed: chamber plates already reach 20 to 28% moisture and membrane squeeze at 1.5 MPa gains only 3 to 5 points. Standard plate ranges are listed under filter plates.
Why should a continuous cutting shop choose a fully automatic filter press?
A fully automatic filter press opens, shifts every plate, drops the cake and recloses in 3 to 6 minutes without an operator, so a cutting shop running 2 to 3 shifts can take 15 to 25 cycles per day from a press that a manual crew would cycle only 3 to 4 times.
Saws run around the clock and the clarifier underflow never stops. A manual press needs someone to shift 80 to 100 plates by hand, 20 to 30 minutes per cycle, and cake left overnight hardens and sticks. Automatic plate shifting with PLC control, cake-release shaking, closing drip trays and optional cloth washing at 1.0 MPa every 20 to 40 cycles solve this.
The payback comes from buying a press with 30 to 40% fewer plates and removing one operator per shift. Our article on automatic vs manual filter press ROI gives the calculation. The automatic models and their control options are listed in the filter press range.
How long does filter cloth last on abrasive stone fines, and which cloth is best?
Filter cloth lasts 3 to 6 months on stone-cutting slurry, shorter on granite (3 to 4 months) and longer on marble (5 to 6 months), and the best choice is a monofilament or monofilament-multifilament polypropylene cloth of 500 to 700 g/m² with a reinforced feed-hole collar.
Abrasion is the failure mode, not blinding. Granite fines at Mohs 6 to 7 and steel grit cut the yarn at the feed hole and plate edges. Fines of 5 to 40 µm bridge on a 40 to 60 µm nominal opening, so a coarse, heavy cloth gives fast filtration and a clear filtrate within a few cycles.
Three details extend life: wear-resistant feed sleeves in the plate centre hole, a slow feed pressure ramp for the first 2 to 3 minutes, and a 0.8 to 1.0 MPa wash every 20 to 40 cycles to remove the calcium carbonate film from marble slurry. Cloth options are listed under filter press cloth, and inspection intervals are in how often filter press cloth should be replaced.
What can be done with the filter cake?
Marble filter cake at 20 to 28% moisture is 95 to 99% calcium carbonate and goes to cement, lime, brick and filler producers; granite cake is used in bricks, paving blocks and road base, and both are accepted at inert landfills at far lower cost than wet slurry.
At 20 to 28% moisture the cake holds its shape, loads with a wheel loader and does not drain in the truck. Slurry at 20% solids has 4 times the mass and is classed as liquid waste in most regions, so switching to cake cuts disposal transport by about 75%.
Why buy a stone slurry filter press from Senjie?
Senjie is a China-based manufacturer of chamber, membrane and fully automatic filter presses, founded in 2014, with equipment supplied to buyers in 40+ countries across Southeast Asia, India, Africa, the Middle East and Latin America. For stone cutting shops, Senjie supplies presses from 630 to 1500 mm with automatic plate shifting, drip trays and PLC control, heavy monofilament cloth, wear-resistant feed sleeves, and matched slurry or diaphragm feed pumps. Each press is sized from block throughput and slurry test data and test-run before shipping. Typical lead time is 25 to 45 days.
Frequently Asked Questions
What cake moisture does a filter press achieve on marble or granite slurry?
20 to 28% moisture on a chamber filter press at 0.6 to 0.8 MPa feed pressure. Granite fines reach 20 to 25% and marble fines 22 to 28%. A membrane press gains only 3 to 5 further points, so it is rarely specified for stone.
How much water can a stone shop recycle with a filter press?
90 to 95% of the circulating water. Losses are the moisture in the cake, evaporation and spray drift. A shop circulating 100 m³/h needs only 5 to 10 m³/h of make-up water once the clarifier and filter press loop is running.
How long does a filter press cycle take on stone-cutting slurry?
20 to 40 minutes including filling, filtration, opening and cake discharge. Stone fines are granular and incompressible, so the chamber fills in 10 to 20 minutes. An automatic press can therefore run 15 to 25 cycles per day.
What size filter press does a granite shop with two gang saws need?
Two gang saws with a polishing line produce 5 to 12 t of dry fines per day. That needs a 1000 to 1250 mm press with 60 to 100 plates running 2 to 4 cycles per day, or a smaller automatic press cycled 8 to 12 times per day.
How long does filter cloth last on stone slurry?
3 to 6 months. Granite and steel grit from gang saws wear the cloth in 3 to 4 months; marble allows 5 to 6 months. Heavy monofilament polypropylene cloth of 500 to 700 g/m² with reinforced feed-hole collars gives the longest life.
Send your daily block throughput, stone type and circulating water flow to the Senjie team for a plate count and quotation via the contact page.