Introduction:

A sludge dewatering machine is a continuous sludge processing device. Due to its low moisture content, it operates stably, features low energy consumption, relatively simple control and management, and easy maintenance, making it widely favored. After sludge is concentrated or digested, it remains in a liquid state and has a large volume, making it difficult to transport and dispose of. To further reduce the moisture content and minimize the volume of sludge for easier transportation, it is necessary to dehydrate the sludge.

Types:

The sludge from wastewater treatment plants can be categorized into three main types: physical-chemical sludge, biological sludge, and a combination of both. Each type of sludge has different requirements for dewatering equipment. Commonly used models in China include centrifugal, belt filter, screw press, and plate and frame types. For the dewatering of settled sludge, the selection and proper use of flocculants are crucial. Effective flocculation significantly improves the sludge’s dewatering process.

The following is a brief introduction to the actual use of the three models for selection:

Centrifugal: Suitable for all three types of sludge, but it consumes a lot of energy and generates significant noise due to high rotational speeds. Filter belt: Suitable for physical and chemical sludge, with low moisture content in the filter cake. However, it performs poorly with mixed and biochemical sludge, requires a large amount of return sludge, uses a lot of backwash water, and has high energy consumption and complex maintenance. Screw ring: The first generation of dewatering machines, represented by Japanese models, have been in use in China for 3-4 years. However, they have a relatively low production capacity.

Technical principle:

New separation technology: the organic combination of spiral pressure and static and dynamic rings forms a new separation technology integrating concentration and dehydration, which adds an advanced dehydration mode to China’s environmental protection sewage treatment field.

Energy and water conservation: By utilizing the continuous rotational kinetic energy of the dynamic and static rings, the system achieves self-cleaning within the cylinder, preventing the filter gap from clogging. This replaces the high-pressure washing of the old generation of filter cloths and belt filter plates, significantly reducing industrial water usage (13,000 tons of water saved per unit annually). The main screw shaft operates at a low speed (3-5 revolutions per minute), which reduces mechanical wear and extends the equipment’s lifespan. The main motor consumes less than 1.1 kW/h, saving up to 50,000 kWh of electricity per unit annually.

Processing capacity doubled: The second-generation dewatering machine has a processing capacity that is twice that of the first generation. A single 303 unit can handle 10,000 tons of sludge from 10,000 tons of sewage and can be designed to achieve a sludge dewatering depth of 50-40%, with a single process capable of handling 10,000 to 30,000 tons of sewage treatment. Domestic innovation: The pressure adjustment plate uses an elastic automatic adjustment mechanism, which naturally balances the internal pressure of the sludge in the dewatering section, effectively extending the service life of the dynamic and static ring discs.

Green environmental protection: the whole machine is sealed and can be directly observed. The shell is easy to disassemble and install, no sewage leakage, no secondary pollution, noise <45 db, so that the sludge machine room environment is beautiful and civilized production.

There is no filter cloth hole or other blocking parts in the ring sheet sludge dewatering machine: the operation is safe and simple, according to the customer’s operating time. Combined with the automatic control system, it can be programmed to achieve automatic unattended operation (it should have a considerable amount of sludge).

Working Principle:

1. Plate and Frame Sludge Dewatering Machine: In a sealed environment, sludge is pumped into the machine under high pressure. The sludge is then compressed by the plates and frames, allowing the water to be drained through the filter cloth, achieving dewatering.

2. Belt Sludge Dewatering Machine: Two tensioned filter belts carry the sludge layer, which passes through a series of regularly arranged roller presses in an S-shape. The tension in the filter belts creates pressure and shear forces on the sludge layer, squeezing out the capillary water and achieving sludge dewatering.

3. Centrifugal Sludge Dewatering Machine: This machine consists of a screw conveyor with a hollow shaft and a transfer device. The sludge is fed into the drum via the hollow shaft, where it is thrown into the drum cavity by the centrifugal force generated by high-speed rotation. Due to their different densities, solid and liquid components separate. The sludge, propelled by the screw conveyor, is continuously discharged from the outlet at the conical end of the drum; the liquid in the liquid ring layer continuously discharged from the outlet at the conical end of the drum; the liquid in the liquid ring layer continuously overflows through the weir and is discharged to the outside of the drum by gravity.

4. Stacked Sludge Dewatering Machine: This machine consists of a filter body formed by the layering of fixed and movable rings, with a spiral shaft running through them. The sludge is fully dehydrated through gravity concentration and the internal pressure created by the backpressure plates during the advancement process. The filtrate is discharged through the filter gaps between the fixed and movable rings, while the sludge cake is discharged from the end of the dewatering section.