Name: Screw Press
Brand: JX Filtration

Description

JX Filtration offers a full range of screw presses from compact laboratory-scale units to high-capacity industrial models, with flexible customization options to suit various throughputs and material properties. Designed for continuous operation, our screw presses combine screw extrusion with dynamic-static ring filtration to achieve efficient solid-liquid separation with minimal energy input and low maintenance requirements.

A screw press, also known as a spiral press or screw type solid-liquid separator, is a continuous mechanical dewatering device that applies progressive extrusion force to separate liquids from solids. Unlike batch-operated filter presses, the screw press operates continuously, with material advancing along a rotating screw shaft while water is progressively squeezed out through a surrounding screen or filter ring assembly. This makes it particularly suitable for materials with fibrous content, high moisture variability, and moderate-to-high throughput requirements.

Working Principle

The screw press operates through two integrated stages—gravity concentration and progressive extrusion.

Concentration Stage: Material enters the feed hopper, where a perforated filter plate provides preliminary drainage. As the screw shaft begins rotating, material is conveyed forward. In the initial section, the screw flight depth is relatively large, allowing free water to drain through the screen under gravity before the material reaches the pressing zone.
Extrusion Stage: As material advances along the screw, the screw pitch gradually decreases while the screen aperture remains constant. This continuously reduces the screw cavity volume, generating increasing internal pressure. The dewatering body consists of a stack of fixed and moving rings—the screw shaft runs through this assembly, and the relative movement between rings creates a continuous self-cleaning effect that prevents clogging. Water is forced out through the screen or ring gaps, while the dewatered solids are discharged through the outlet. A back-pressure plate or resistance device provides additional pressing before final discharge, and its pressure can be adjusted to control cake dryness.

Advantages

Continuous fully automatic operation – Uninterrupted feeding, pressing, and discharge support 24/7 production with minimal manual intervention
Low energy consumption – Main motor power can be as low as 0.75 kW depending on model; no heat source or drying equipment required
No chemical flocculants required – Fine screen apertures of 0.7–1.0 mm eliminate the need for polymer dosing systems in many applications
Wide material adaptability – Handles both high-fiber materials and low-concentration slurries; sludge concentrations as low as 0.2%–0.3% can be processed directly without pre-thickening
High continuous throughput – Optimized screw parameters prevent clogging and backflow, with capacities from hundreds to over 10,000 kg/h
Wear and corrosion resistant – Key components available in SS304, SS316, and SS316L with wear-resistant coatings
Low maintenance – Low-speed operation with no filter cloth to replace; only periodic lubrication and bolt checks required
Customizable for specific materials – Screw pitch, diameter, screen aperture, and motor power tailored to individual process requirements