Multi-disc
Screw Press
A fully automatic, low-energy sludge dewatering machine combining integrated flocculation, gravity thickening, and progressive screw pressing in a single compact unit. Dewatered cake solids of 15–25% DS achieved without pre-thickening — continuous 24-hour operation with minimal operator attention.
What Is A
Multi-disc Screw Press?
The Multi-disc Screw Press (叠螺脱水机) is a continuous, fully automatic sludge dewatering machine that integrates polymer flocculation, gravity thickening, and mechanical pressing into a single compact unit. Unlike belt filter presses or centrifuges, it requires no pre-thickening of the feed sludge and operates at very low speed — resulting in extremely low energy and wash water consumption.
The dewatering drum consists of a variable-pitch auger running through a stacked ring assembly of alternating fixed and moving discs. Every second disc is fixed to the barrel assembly; the intermediary discs are free to move. As the auger turns, the orbital movement of the intermediary discs continuously self-cleans the gaps between rings — preventing blinding without any wash water spray required during normal operation.
Dilute sludge is dosed with polymer in the integrated flocculation tank to form flocs. The floc suspension overflows into the thickening zone where free water drains through the ring gaps. The thickened sludge is progressively transported into the dewatering zone where decreasing auger pitch and narrowing ring gaps apply increasing compressive pressure, producing a dry, handleable sludge cake at the discharge end.
- Municipal wastewater treatment plant biosolids dewatering
- Waste activated sludge (WAS) and mixed sludge
- Food and beverage industry process sludge
- Oily sludge from industrial wastewater treatment
- Paper & pulp mill sludge dewatering
- Aquaculture and livestock wastewater treatment
- Leachate treatment residual sludge
Why Choose Our
Multi-disc Screw Press
Self-Cleaning Disc Stack
Moving intermediary discs orbit continuously as the auger turns, clearing the gaps between fixed discs automatically — no wash water spray nozzles, no blinding, no clogging during operation.
Variable-Pitch Auger
Auger pitch decreases progressively from thickening zone to dewatering zone. Combined with narrowing ring gaps, this creates a steadily increasing compression ratio — maximising cake dryness.
Integrated Flocculation Tank
Built-in polymer dosing and flocculation tank with bending mixing vanes ensures thorough polymer-sludge mixing before the dewatering zone — no separate flocculation equipment required.
Handles Oily Sludge
Spray port in the main body of the screw stack prevents internal blockage from oily or greasy sludges — types that would blind or foul a belt press within hours of operation.
Heat-Treated Screw Shaft
Auger shaft subjected to heat treatment — increased rigidity and wear resistance against abrasive sludge components. Extended service life with less frequent component replacement.
Flat Moving & Fixed Rings
Flat disc geometry minimises wear compared to tapered designs. Ring assemblies are sectional — each section can be disassembled and replaced independently without removing the entire drum.
Mud Resist Ring & Board
Mud-resist ring and baffle board prevent sludge migration back along the barrel — maintaining forward transport efficiency and clean separation of the thickening and dewatering zones.
Adjustable Overflow Height
Flocculation tank overflow level is adjustable — accommodating varying feed sludge concentrations and flow rates, giving operators control over residence time and floc formation quality.
Small Footprint
Compact, fully enclosed unit — significantly smaller floor area than equivalent belt filter press or centrifuge installations. Suitable for retrofitting into existing dewatering building footprints.
How It Works
Feed & Dose
Dilute sludge is fed to the integrated flocculation tank. Polymer is dosed and mixed to form stable flocs. Excess sludge overflows to drainage.
Thickening Zone
Floc suspension overflows into the barrel. Free water drains through the ring disc gaps by gravity. Sludge thickens as it moves along the auger.
Dewatering Zone
Decreasing auger pitch and narrowing ring gaps apply progressive compression. Filtrate is discharged. Sludge cake forms under increasing pressure.
Final Compression
End plate applies back-pressure from the discharge side. Volume compression effect squeezes remaining water — cake solids reach 15–25% DS.
Cake Discharge
Dry sludge cake exits through the cake discharge outlet. Moving discs self-clean continuously throughout all stages — no wash-down required.
Structure & Process
Flow Diagrams
Engineering Detail
Flat Moving & Fixed Rings
Flat disc geometry reduces ring wear compared to tapered designs. Sectional assembly — individual sections removable and replaceable without dismantling the full drum. Easy maintenance access.
Integrated Polymer Dosing
Built-in flocculation tank with bending mixing vanes ensures thorough, uniform polymer-sludge contact. Overflow height is adjustable — accommodating varying feed concentrations without external equipment.
Adjustable Overflow Control
Flocculation tank overflow port height is adjustable, controlling the liquid level and residence time within the flocculation zone — fine-tuning floc formation quality for different sludge types.
Technical Specifications
| Parameter | Value / Range |
|---|---|
| Dewatering Principle | Variable-pitch auger + alternating fixed & moving disc stack |
| Feed Sludge Concentration | 0.2 – 8% DS (no pre-thickening required) |
| Cake Solids Content | 15 – 25% DS (depending on sludge type and polymer dose) |
| Disc Material | Stainless steel 304 / 316L (project-specific) |
| Auger Shaft Treatment | Heat-treated for increased rigidity and wear resistance |
| Self-Cleaning Mechanism | Continuous orbital movement of moving discs — no wash water required |
| Backwash Spray Port | Provided in main barrel for oily sludge applications |
| Flocculation Tank | Integrated; adjustable overflow height; bending mixing vanes |
| Control System | PLC automatic control; 24-hour unattended operation |
| Operation Mode | Continuous |
| Noise Level | Low — slow-speed auger rotation |
| Footprint | Compact — significantly smaller than equivalent belt press or centrifuge |
| Note: The Multi-disc Screw Press is configured per project. Screw diameter, number of stacks, and throughput capacity are selected based on feed sludge type, concentration, and required cake dryness. Contact us with your sludge characterisation data for a project-specific sizing proposal. | |
Request A Quote
Or Technical Consultation
Tell us your sludge type, feed flow rate, solids concentration, and target cake dryness — we will size the right screw press configuration and provide a full system proposal including polymer dosing system.