Direct Answer

A decanter centrifuge is a continuous horizontal separator. It uses high-speed rotation to generate centrifugal force and efficiently separate solids from liquids.

With a large processing capacity and a high level of automation, it can run continuously for 24 hours.

It is widely used in environmental protection, chemical, food, pharmaceutical, mining and other industries.

Main Components of a Decanter Centrifuge

The Drum

• The drum is the main load-bearing part of the centrifuge.

• Its diameter, length and cone angle directly affect separation efficiency, processing capacity and final moisture content.

• At high rotating speeds, it creates a strong centrifugal field for solid-liquid separation.

• It is usually made of 304 or 316L stainless steel.

The screw conveyor

• The screw conveyor is mounted inside the rotating drum and features a wear-resistant surface.

• Its main job is to continuously push sludge from the drum wall to the discharge port.

• It can handle tough materials like sand and fibers in the sludge.

The differential

• The differential is key to controlling the speed difference between the drum and the screw.

• The differential can be variable, allowing automatic adjustment of the speed difference to match process conditions and fluctuations in solids loading, which optimizes separation efficiency and prevents overloads.

• By adjusting this speed difference, we can control the discharge speed, cake dryness, and separation efficiency.

Drive System

• It usually uses a dual-motor drive.

• One motor drives the drum, and the other works with the differential to drive the screw.

• Advanced drive systems may use specialized software integrated with VFDs or PLCs for automatic adjustment and improved efficiency.

• The power output is stable with a wide speed range.

• Explosion-proof motors are available for special conditions such as chemical and hazardous waste treatment.

Feed system

• It consists of a feed pipe and a distributor.

• It feeds materials evenly and steadily into the drum separation zone.

• Level-adjustable plates are used to control the pond depth and facilitate precise phase separation, ensuring optimal operation and product quality.

• Some liquid outlet systems incorporate energy recovery features, improving energy efficiency and reducing operational costs.

• This design avoids unbalanced vibration and ensures stable operation and consistent separation.

Discharge system

• It has a solid discharge port for discharged solids (solid phase) at the conical end, and a liquid discharge port for separated liquid phases at the cylindrical end of the drum.

• This configuration allows the decanter centrifuge to continuously obtain separated solids and liquids during operation.

• The design is smooth and less likely to clog.

• The liquid level can be adjusted based on processing needs.

The frame and cover shell

• The frame uses a high-strength welded structure with shock absorbers to reduce vibration and noise.

• The cover provides sealing, protection, and odor control. Its closed design minimizes odor and reduces emissions, helping to protect the environment.

• The design allows easy access for maintenance and servicing, enabling technicians to safely and efficiently reach critical areas of the decanter centrifuge.

• It meets safety and environmental requirements in the workshop.

PLC control system

• It acts as the control center of the machine.

• It supports automatic feeding, speed adjustment, differential control, fault alarm, and emergency stop.

• The touchscreen shows real-time data such as rotating speed, processing capacity, and running status.

• Operation is simple and straightforward.

The Operating principle of the Decanter Centrifuge

The core working principle of the Decanter Centrifuge is to achieve the separation of materials of different densities through the centrifugal force field.

The slurry enters the rotating drum through the feed pipe and is gently accelerated to match the drum's rotating speed.

Decanter centrifuges can handle large volumes of slurry.Some models can process 100–200 cubic meters per hour.

Under centrifugal force up to 4,000 times gravity, dense solids are thrown to the drum wall and form a cake.The lighter liquid forms a clear inner layer.

The differential mechanism is key to the machine's performance.The screw spins the same way as the drum but at a slightly different speed, controlled by the differential gear.

It keeps pushing solids on the drum wall toward the conical end to be discharged. At the same time, clarified liquid flows out through the overflow ports on the cylindrical end.This process enables continuous solid–liquid separation.

Process flow sequence

1. Feed enters through stationary pipe into screw center

2. Material accelerates to drum speed in feed zone

3. Centrifugal force separates solids to outer wall

4. screw conveyor cake along conical section toward discharge

5. Clarified liquid overflows weirs at the opposite end of the drum

6. Solids and liquid exit continuously through separate outlets.

2-phase vs 3-phase decanter centrifuge operation

Two-phase decanter centrifuges are the most common type. They separate liquids from suspended solids, such as brine with salt crystals or process liquid with catalyst particles.

Solids move to the drum wall, while the liquid forms an inner pool.

Three-phase decanter centrifuges handle two immiscible liquids and solids simultaneously.

This is especially useful in biodiesel production, oil sludge treatment and similar applications.

Due to density differences, the drum forms three distinct layers:

• Solids on the outermost layer

• Heavy liquid (typically water) in the middle

• Light liquid (oil or organic solvent) near the center

Summary

Thanks to its reliable working principle and sturdy structure,the decanter centrifuge provides continuous, automatic and efficient solid-liquid separation. It performs well in many industrial applications.

Contact Penoy to offer solutions

For customized solutions, quotations or on-site technical support,please feel free to contact Penoy.We provide professional and efficient solid-liquid separation solutions.

FAQ

Q:What is the typical processing capacity

A:Throughput depends on the model, feed solids content and process requirements.It can range from a few tons to over a hundred tons per hour.We will match the right machine and parameters for your specific working conditions.

Q:To what level can the moisture content of the filter cake be controlled?

A:Cake moisture content depends on the material characteristics, bowl speed, differential speed and other parameters. In standard sludge dewatering applications, it can be kept below 60%.The exact result can be further optimized through tests or on-site commissioning.

Q:Does the equipment require 24-hour manned supervision?

A:It comes with a standard PLC automatic control system. It supports automatic feeding, speed/differential adjustment, fault alarm and emergency stop. No full-time operator is needed daily; only regular checks are required.

Can one decanter centrifuge handle different materials?

It's possible, but you'll need to adjust parameters like speed, differential and liquid level based on the material properties.If you're processing materials with very different characteristics, please let us know in advance.We recommend a process test if needed, to ensure good separation results.

Is the equipment prone to clogging? Is it easy to maintain?

The discharge port has a smooth design.Together with the adjustable-speed screw conveyor, it is not easy to clog under normal working conditions.The main wearing parts are the screw blades and bearings.Maintenance is simple, and overall operating costs are low.