Stone fabrication shops, granite quarries, marble cutting plants, and quartz countertop facilities all generate the same problem: sawing wastewater loaded with 5-15% fine mineral slurry. A purpose-built stone industry filter press dewaters that slurry to 60-70% solid cake, recovers 90%+ of process water for closed-loop reuse, and enables landfill disposal or beneficial reuse (cement filler, ceramic body, decorative aggregate) of the cake.
Why Stone Slurry Needs a Specialized Press
Stone sawing slurry is fine (often 50% under 20 µm), abrasive (Mohs 5.5-7), and chemically near-neutral. Three challenges drive the press spec:
- Cake stickiness — fine quartz and feldspar cakes don’t release from cloth easily; vibration or pneumatic shakers are essential
- Cloth abrasion — fine sharp particles wear filter cloth faster than typical mineral duties; heavy-duty woven polypropylene with monofilament face is preferred
- Process water recovery — most stone shops aim for closed-loop water systems, which requires filtrate suspended solids under 50 mg/L
When to Use Filter Press vs Settling Tank Only
A settling tank (clarifier) alone gets you 30-40% solids in underflow — not dry enough for landfill or reuse. Adding a filter press downstream takes that underflow to 60-70% solid cake, simultaneously polishing the supernatant for recycle. For shops with under 5 m³/h slurry production, sometimes a centrifugal decanter is cheaper; above that, filter press wins on operating cost. For more applications in this segment, see our stone and building materials page.
Common Stone Industry Applications
- Granite slab fabrication — gang-saw and bridge-saw cooling water
- Marble cutting plants — soft mineral, especially fine slurry
- Engineered quartz — countertop manufacturing wastewater
- Quartzite quarries — wire-saw and water-jet recovery
- Slate processing — splitting and trimming wastewater
- Ceramic tile — body preparation slurry, glaze application wastewater
- Cement plant grinding slurry — wet grinding circuits
Specifications & Customization Options
- Filter area: 30 – 300 m² per press (typical stone shop range)
- Plate size: 800-1500 mm
- Operating pressure: 6-12 bar
- Cake discharge: Vibration motors + air-blow knockers (essential for sticky stone cake)
- Cloth: Heavy-duty woven polypropylene with monofilament face; 10-25 µm rating
- Frame: Carbon steel epoxy-coated (most installations) or 304 stainless for high-humidity environments
- Optional preconditioning: Anionic polymer dosing for ultra-fine slurries
FAQs
What cake moisture should I expect from stone slurry? 30-40% moisture (60-70% solids) is standard for chamber-only operation. With membrane squeeze, you can reach 20-25% moisture, which is overkill for landfill but useful when selling cake to cement plants as filler.
Can the cake be sold instead of landfilled? Often yes. Granite and marble cakes (calcium and silicate rich) are accepted by cement plants as alternative raw material, by ceramic plants as body component, and by aggregate producers as filler. Some facilities even sell engineered quartz cake back to the original manufacturer.
How does water recovery work? Filtrate (typically 15-40 mg/L suspended solids) returns directly to the saw cooling water tank. Make-up water demand drops by 90-95% compared to once-through operation — important in arid regions and for environmental permits.
Need a press for your stone shop? Contact Senjie with your saw type, daily slurry volume, current dewatering approach, and stone type — we’ll spec the right plate size, cloth, and discharge automation.