Screw Presses for STP and ETP Sludge
QuaSys Inc. supplies two screw press brands: Krofta and Quatech. Quatech is QuaSys Inc.'s own brand. A screw press dewaters sludge continuously, using little power and needing little operator attention, which suits biological sludge from STP and ETP plants.
Krofta vs Quatech
| Brand | Models | Inlet flow at 1% consistency | Power |
|---|
| Krofta | KSP 15 to KSP 700 | 1.5 to 76 m³/h | 0.37 to 4.5 kW |
| Quatech | QSP 15 to QSP 750 | 1.5 to 75 m³/h | 0.37 to 4.5 kW |
How a Screw Press Works
A screw press dewaters sludge continuously by feeding it through a slowly rotating screw inside a cylindrical screen. As the screw's pitch decreases along its length, the sludge is progressively compressed, squeezing out water through the screen while the solid cake is discharged at the outlet. Polymer is typically dosed ahead of the press to flocculate solids and improve dewatering.
Unlike batch-operated filter presses, a screw press runs continuously at low RPM, which is why it uses much less power and needs less manual attention.
Screw Press vs Filter Press
Both dewater sludge, but they suit different situations. Screw presses excel at continuous-duty biological sludge, while filter presses achieve higher cake dryness for chemical and industrial sludge. Read our full screw press vs filter press comparison and total cost of ownership breakdown.
Technical Specifications
| Parameter | Value |
|---|
| Capacity | 1 to 500 kg DS/hr |
| Cake dryness | 18–25% dry solids |
| Operation | Continuous |
| Power consumption | 60–80% lower than an equivalent centrifuge |
Applications
- STP biological sludge dewatering
- ETP sludge dewatering
- Food and beverage industry sludge
- Paper and pulp industry sludge
Why Choose QuaSys Inc. for a Screw Press?
QuaSys Inc. supplies screw presses sized to your actual sludge volume and characteristics, with polymer dosing guidance during commissioning to optimise cake dryness from day one. AMC and spare parts support is available across India.
Specifications & pricing last verified: 03 Jul 2026
Frequently Asked Questions — Screw Press
Which screw press brands does QuaSys supply?+
QuaSys Inc. supplies Krofta and Quatech screw presses across India. Quatech is QuaSys Inc.'s own brand. Call +91 95408 15659.
What is the price of a screw press?+
QuaSys Inc. does not publish fixed prices online. A screw press is quoted by model, materials and accessories such as polymer dosing. Share your sludge details for a specification-based quote.
What cake dryness can a screw press achieve?+
Typically 18 to 25% dry solids depending on the sludge, and about 20% for municipal or bio sludge, with correct polymer dosing.
Screw press or filter press: which should I choose?+
Screw presses suit continuous-duty biological sludge with low power use. Filter presses reach higher cake dryness for chemical and industrial sludge but run in batches.
What do you need to size a screw press?+
Your sludge type, flow in m3/h, solids concentration and the dryness you need. We then recommend a model and polymer dosing approach.
Krofta Screw Press.jpg)
Quatech Screw Press