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Types of Dewatering Equipment

Dewatering equipment plays a vital role in separating liquids from solids in various industries. There are various types of dewatering equipment on the market, such as centrifugal dewatering machines, belt filter presses, screw press dewatering machines, sloped screen separators, multi disc screw presses, etc. Tianzhong Machinery is a leading supplier of solid liquid equipment and solutions, which offers single, twin and multi-disc screw presses, as well as sloped screen separators. Please follow us to find out what are they and what are the differences.

1. Centrifugal Dewatering Machine:

Centrifugal dewatering machines utilize centrifugal force to separate solids from liquids by spinning them at high rotation speeds. These machines consist of a rotating drum with a hollow shaft and a screw conveyor. When feeding the sludge into the drum, the high-speed rotation generates centrifugal force. The heavier solid particles are thrown against the drum’s inner walls, forming a solid layer, while the lighter liquid forms a separate layer. The solid layer is then transported by the screw conveyor to an outlet, while the liquid is discharged separately. They are often used in wastewater treatment plants, food processing, and chemical industries.

2. Belt Filter Presses:

Belt filter press is particularly used in the wastewater treatment process. It uses two tensioned filter belts to squeeze and shear the sludge layer, effectively separating liquid from solids. The sludge is fed onto a continuous belt, which moves slowly through a series of rollers. As the belt moves, the liquid is drained away through the belt under gravity and the pressure of the rollers. The sludge undergoes repeated squeezing and shearing through the rollers, reducing its water content. Finally, the solid cake is scraped off by a discharge scraper. After discharging, the filter belt is cleaned and enters the next cycle.

Centrifugal Dewatering Machine
Centrifugal Dewatering Machine
Belt Filter Press
Belt Filter Press

3. Screw Press Dewatering Machine:

Screw press dewatering machines uses a screw mechanism to squeeze and press the material to separate liquids from solids. These machines are suitable for processing animal waste, biogas slurry, paper pulp and other organic materials. The material is fed into the screw press, and as the screw turns, it moves the material along its length. With the decreasing pitch of the screw, the material is compressed. This compression helps to separate the liquid from the solid. The separated liquid flows out through the screen while the solid retains in the screen and continues to move along the screw. And they are finally discharged at end of the machine.

4. Slope Screen Separators:

Slope screen separators are specifically designed for dewatering animal waste. These machines are suitable for the separation of low solid content materials, such as water-flushed manure, waste-soaked manure, wastewater from the slaughterhouse. The material needs to have a high moisture content of over 90% and solid particles larger than 0.3 mm. The dewatered solid is with a moisture content of around 80%.

This machine is to allow liquid to drain from the solids by utilizing the force of gravity and the inclined screen surface. The material flows over an overflow weir and is evenly distributed onto the screen surface. As the liquid flows down the screen, the solid particles ratain on the screen surface and gradually slide down to the lower end of the screen due to gravity. Then the solid material will go through a screw press to further remove the liquid.

5. Multi Disc Screw Press

A multi-disc screw press uses moving and fixed rings and a screw mechanism to achieve efficient dewatering and solid-liquid separation. It’s commonly used in industries such as wastewater treatment, food processing, and other applications.
When the slurry is fed into the screw press, the helical drive shaft rotates. The moving rings move, and some liquid flows out from the gaps between the moving rings under gravity. The sludge moves forward continuously along with the rotation of the screw. As the pitch of the screw gradually decreases, reducing the gaps between the rings, the increasing pressure squeezes liquid out. The water content of the dewatered solids is about 75-80%.

Continuous Screw Press
Continuous Screw Press
Inclined Screen Separator
Inclined Screen Separator
Inner Structure of Multi Plate Screw Press
Multi Plate Screw Press

Differences Between Belt Press, Centrifuge and Multi Disc Screw Press

Among the types of dewatering equipment mentioned above, belt press, centrifyge and multi disc screw press are commonly used to process sludge. Below are some differences among them.

Machines Belt Press Centrifuge Multi Disc Screw Press
Noise Level Low High Low
Power Consumption Medium High Low
Dewatered Sludge Moisture Content 75-80%
Working Method Not Continuous Continuous Continuous
Footprint Large Small Small
Wash Water Volume Large Medium Small (self-cleaning)
Operating Costs Moderate Low Low
Disadvantages High wash water volume; Filter belt clogging High power consumption, High noise Small processing capacity

Conclusion

Understanding the differences between various types of dewatering equipment will help you choose a suitable machine for your specific applications. Our dewatering machine find wide applications across diverse applications, especially manure management, dewatering spent grains, paper pulp industry, processing agricultural waste, extracting juice from fruit and vegetable, etc. We have helped more than 1,000 clients with their dewatering projects. If you have any questions, please feel free to contact us. Our professional team is ready to help!