Stacked screw sludge dewatering machine

• Product Overview

The Spiral-Stacked Sludge Dewatering Machine is a sludge treatment equipment designed and manufactured by our company, utilizing a combination of a screw shaft and dynamic-static annular plates for mechanical dewatering. Inspired by the principle of screw pumps, this product achieves continuous sludge conveyance, compression, and dewatering through the relative movement of the dynamic and static annular plates driven by the screw shaft. As a low-speed, enclosed dewatering device, it provides an energy-efficient, low-water-flushing-consumption, and relatively simple operation and management solution for sludge dewatering with high organic content in municipal and industrial sectors.

• Structure and Working Principle

1. Core structural composition

The core of the device is a dehydration body formed by coaxial stacking of multiple component groups, primarily comprising:

• The dehydration body: consists of a spiral shaft and multiple fixed rings (static rings) alternately overlapped with moving rings (dynamic rings). The precision filter gaps between the ring plates are crucial for achieving solid-liquid separation.
• The drive device includes a motor and a reducer, which drive the screw shaft to rotate at low speed.
• Flocculation mixing tank: Equipped with a mixer to ensure thorough mixing and reaction between sludge and high-molecular flocculant, forming dense flocs.
• The filter liquid collection tank and frame: Collects the filtered liquid extracted during pressing. The entire support structure is typically made of 304 stainless steel, which exhibits excellent corrosion resistance.
• Control system: Integrated electronic control cabinet, capable of controlling drive, stirring, and flushing functions.

2. Working Principle

The device follows an integrated process of "chemical conditioning—concentration—dehydration":

1. After flocculation and mixing in the flocculation tank, the sludge is slowly pushed into the front section of the dewatering unit—the thickening section. Under the gradual rotation of the screw shaft, the flocs are initially compressed, allowing most of the free water to be discharged through the filter gaps between the stationary and rotating rings, resulting in preliminary thickening of the sludge.
2. Pressing Dewatering: The concentrated sludge is propelled forward by the spiral shaft into the dewatering section. As the spiral pitch gradually decreases and the back pressure plate generates outlet pressure, the spatial pressure on the sludge progressively increases. During the relative movement between the stationary and rotating annular plates, the sludge undergoes continuous shearing and compression, further separating and discharging capillary-bound water to form a sludge cake.
3. Self-cleaning and sludge discharge: During rotation, the spiral shaft drives the moving ring plate to exhibit slight movement, which helps prevent filter slit clogging. The pressed and dehydrated sludge cake is continuously extruded through the gap between the back pressure plate and the end of the dewatering body. During short-term shutdowns, the automatic flushing function can be activated to maintain internal cleanliness.

• Core technical features

1. Low-speed operation ensures energy efficiency and durability: The equipment operates at a low rotational speed (typically only 2-5 RPM), with a small main motor power consumption, resulting in relatively low energy usage. Mechanical wear is minimal, and the overall design life may be prolonged.
2. Self-cleaning capability and low clogging risk: The unique dynamic-static annular plate with relative floating structure generates minute gap variations during operation, providing inherent self-cleaning and anti-clogging properties, making it particularly suitable for organic sludge prone to adhesion.
3. Fully enclosed design with environmental benefits: The dehydration process occurs in a nearly completely sealed environment, effectively controlling odor dispersion and filtrate splashing, thereby improving the operational environment.
4. Continuous automatic operation with simplified management: The entire process, from sludge intake, chemical dosing, dewatering to sludge discharge, can be fully automated. Routine operations mainly involve chemical dosing and inspection, with minimal manual intervention.
5. Low water consumption for rinsing: The system primarily relies on the relative motion between annular plates to maintain flow, with only brief rinsing required after daily shutdown. This results in significantly lower water consumption compared to belt filter presses.

• Main technical parameters

• Typical Application Fields

This equipment is particularly suitable for treating sludge with high viscosity, high oil content, and abundant organic matter.

• Municipal sewage treatment: The residual activated sludge from urban sewage treatment plants and the dewatered sludge after anaerobic digestion.
• industrial waste disposal ：

• High organic sludge from food processing (meat, starch, soy products), brewing, pharmaceutical, etc.
• Dewatering of oily sludge from petrochemical plants and oil fields (requires targeted equipment selection and conditioning).
  • Wastewater from breeding and slaughtering: sludge generated from the treatment of livestock manure in farms and wastewater from slaughterhouses.
  • Other areas: for projects with relatively small sludge production or as a backup dewatering unit for large projects.