Centrifuges, including decanter centrifuges, are commonly used in a wide range of industrial applications. However, proper operation is essential to ensure safety, efficiency, and equipment longevity. To help users operate the equipment correctly and reasonably, this guide outlines key recommendations from decanter centrifuge manufacturers, focusing on two main phases: before use and during operation.

1. Pre-Operation Checklist: What to Do Before Using a decanter centrifuge

Manufacturers stress that careful preparation is critical to safe and effective operation. The following steps should be followed before each use:

Positioning and Setup

Place the centrifuge on a stable, level, and vibration-free surface to ensure accurate operation and avoid mechanical stress.

Safety Precautions

Do not place any objects on the cover or control panel of decanter centrifuge.

Samples must be placed symmetrically to avoid imbalance and vibrations.

Ensure that the compression nut is properly tightened before operation to prevent components from dislodging during high-speed rotation.

Component Inspection

Check the rotor for signs of corrosion, dents, or deformation.

Inspect the bowl of decanter centrifuge for cracks, aging, or wear. If any issues are found, the unit must not be used and should be serviced by qualified personnel.

2. Operational Safety: Guidelines While the Centrifuge is Running

Once the decanter centrifuge is in use, the following guidelines must be observed:

Speed and Performance

Ensure the rotation speed stays within the specified range to maintain equipment integrity and prevent accidents.

If abnormal vibrations, noises, or speed fluctuations occur, stop the machine immediately and investigate the issue before resuming operation.

Door and Lid Safety

Do not open the centrifuge door while it is in operation. Doing so can be extremely dangerous due to the high-speed rotation of internal components.

Balance and Load

Always load the centrifuge symmetrically, with equal weight in opposite positions. An unbalanced rotor can damage the machine and pose a safety risk.

Operating Time

Limit continuous operation to a maximum of 60 minutes to avoid overheating or mechanical strain.

By following these key guidelines provided by decanter centrifuge manufacturers, users can ensure safe operation and prolong the lifespan of the equipment. Proper installation, inspection, and handling—both before and during use—are essential for effective sludge separation and process reliability.

For any uncertainties or specific operational scenarios, it is always recommended to consult the manufacturer’s technical team or user manual for tailored guidance.

A decanter centrifuge is a powerful piece of equipment used to separate mixtures of two or three components (typically liquid-solid or liquid-liquid-solid) based on differences in density. To ensure safe, efficient, and effective operation, the following steps and precautions should be followed:

1. Principle of Operation

The decanter centrifuge operates on the principle of centrifugal sedimentation. During operation:

The main motor drives two pulleys, which in turn rotate the bowl (drum) and the scroll (screw conveyor).

The rotation is managed through a differential gearbox (cycloidal or planetary) that maintains a constant differential speed between the bowl and scroll.

This differential allows the screw to convey solids toward the discharge while the bowl spins at high speed to separate solids from liquids.

2. Importance of Balance

To achieve optimal separation and prevent equipment damage, proper balance is critical:

The decanter centrifuge bowl, rotor, and all components must be precisely balanced before operation.

Centrifuge tubes and their contents must be balanced by weight according to the manufacturer’s specifications. For ultracentrifuges, the weight difference between paired tubes should not exceed 0.1 g.

If using centrifuge tube sleeves, ensure that the sleeves are balanced and not interchanged between different centrifuge models.

3. Loading and Setup

Before starting the centrifuge:

Ensure even and symmetrical loading of the centrifuge tubes into the rotor or drum.

Close and securely fasten the centrifuge cover.

Turn on the power supply, and set the operating parameters including:

Bowl speed (RPM)

Differential speed

Centrifugation time

(If applicable) Temperature, vacuum level, and feed rate

4. During Operation

Monitor the unit for vibration, noise, or imbalance, and ensure smooth operation.

Most modern decanter centrifuges are equipped with automatic control systems that manage speed, temperature, timing, and safety interlocks.

5. Stopping and Unloading

As the set separation time approaches, gradually reduce speed using the control panel or allow the automatic system to initiate deceleration.

Wait for the drum to come to a complete stop naturally.

Open the cover and carefully remove the centrifuge tubes or inspect the discharge outlets.

Turn off the power and unplug the unit if not in continuous operation.

6. Cleaning and Maintenance

After each use:

Clean the bowl, scroll, centrifuge chamber, tubes, and sleeves thoroughly to prevent residue buildup.

Inspect wear-prone components such as seals, bearings, and nozzles regularly.

Ensure no foreign objects or residue are left inside the drum to avoid imbalance in future operations.

7. Safety Precautions

Never open the cover while the centrifuge is running.

Avoid operating the centrifuge if it is visibly unbalanced or damaged.

Always refer to the manufacturer’s user manual for specific tolerances and maintenance intervals.

By following these guidelines, you can ensure the decanter centrifuge operates safely, maintains long-term performance, and delivers reliable separation results.

To ensure optimal performance and long-term reliability of a decanter centrifuge, operators must adhere to specific principles and operational guidelines. Neglecting these procedures or deviating from the recommended sequence can lead to inefficiencies, increased maintenance time, and costly operational setbacks—especially when dealing with high-viscosity or high-solid-content liquids. Continue reading →

Both filter presses and Decanter centrifuges are widely used in sludge dewatering and solid-liquid separation, but they differ significantly in their working principles, suitable applications, operational flexibility, and maintenance needs. The following outlines key distinctions and insights drawn from years of practical design experience and user feedback regarding decanter centrifuges:

1. Applicable Media: Not All Sludge Is Equal

Decanter centrifuges are not universally effective across all sludge types.

In particular, sludge with high inorganic content, such as fly ash, poses challenges.

Fly ash tends to adhere to the inner wall of the centrifuge drum, creating resistance and clogging the discharge system.

This issue has been observed in real-life cases, such as a municipal sewage plant in northern China, where the centrifuge failed to operate normally and had to be replaced—leading to significant operational loss.

Filter presses, on the other hand, are generally more suitable for inorganic-rich sludge, offering a more robust performance in handling fine, sticky, or high-density materials like fly ash.

2. Feed Control and Process Stability

Decanter centrifuges:

Offer automated control capabilities, such as adjusting torque and scroll speed in response to variations in feed concentration.

However, these adjustments often still require manual calibration and monitoring.

Changes in feed consistency can affect performance, potentially leading to reduced dewatering efficiency or torque overload.

Filter presses:

Typically operate in batch mode, making them less sensitive to feed fluctuations.

However, they often require longer cycle times and manual intervention for unloading and cleaning.

3. Solid Recovery Rate and Chemical Usage

Decanter centrifuges generally achieve a high solid recovery rate:

This makes them ideal where continuous processing and automation are priorities.

However, not all low-recovery-rate applications are unsuitable—recovered filtrate can be recycled to the head of the treatment process for further separation.

Chemical dosage:

One point of contention is the amount of polymer (e.g., PAM) required.

In a 150,000 m³/day municipal treatment plant using a decanter centrifuge, the measured PAM consumption was approximately 1.7–2.0 kg per ton of dry sludge, which is considered efficient.

In contrast, filter presses in some cases consume up to 20 kg per ton of dry sludge, though this figure can vary widely depending on sludge composition and filtration efficiency.

The Decanter Centrifuge is an advanced separation device known for its low energy consumption, stable performance, and effective solid-liquid separation. It is widely used across various industries including chemical processing, food production, salt refining, mining, and pharmaceuticals. The decanter centrifuge is capable of separating a wide range of materials. Due to its versatility and proven application success, it is advisable to consult with technical experts when selecting a model to ensure the best match for specific processing needs. Continue reading →

GN Separation have recently engineered and delivered a modular hydrovac slurry dewatering system for an international client, offering a high-efficiency, reliable solution for treating construction slurry, drilling mud, and industrial wastewater. This advanced system integrates five key modules—coarse screening, fine screening, desanding & desilting, centrifugation, and chemical dosing—to ensure effective solid-liquid separation and full environmental compliance. Continue reading →

The decanter centrifuge is an advanced separation device known for its low energy consumption, stable operation, and high separation efficiency. It is widely used in industries such as chemical processing, food production, salt refining, mining, and pharmaceuticals. With successful applications across various materials, model selection should be guided by material analysis and expert consultation to ensure optimal performance.

Operational Process and Automation

Decanter centrifuges excel in continuous separation processes, seamlessly performing feeding, dewatering, washing, and discharge in an automated workflow. This high degree of automation enhances production efficiency and process stability.

Separation Principle and Material Suitability

Due to its unique separation mechanism and structural characteristics, decanter centrifuges require careful material-specific adjustments. Before selecting a model, material testing and analysis should be conducted to confirm its applicability and separation efficiency.

How the Decanter Centrifuge Works

Material Entry & Acceleration

The mud-water mixture enters the rotating drum through the feed pipe and screw discharge port.

The main motor generates high-speed rotation, creating strong centrifugal force.

Separation Process

Heavier solid particles settle onto the inner wall of the drum due to centrifugal force.

The screw conveyor (spiral blades) moves relative to the drum, continuously scraping and transporting the separated solids toward the slag discharge port.

The clarified liquid exits the drum through the weir plate opening.

Differential Mechanism & Torque Transfer

The relative movement between the screw conveyor and the drum is controlled by a differential mechanism.

The differential housing is connected to the drum, while the output shaft is connected to the screw conveyor.

The input shaft is powered by an auxiliary motor, which applies braking torque.

Through a planetary gear system, torque is precisely transferred to the screw conveyor at a controlled speed ratio, ensuring continuous separation and discharge.

Types of Decanter Centrifuges

Horizontal Decanter Centrifuges (Spiral Discharge & Sedimentation Type)

Vertical Sedimentation Centrifuges

Each type is designed for specific separation applications, requiring proper selection based on material properties and processing requirements.

Proper handling and maintenance of decanter centrifuges are essential to ensure safety and efficiency. Uncontrolled centrifugal force can cause significant damage, so careful attention to operational procedures is critical. Although decanter centrifuges are straightforward to use, adhering to proper guidelines can prevent malfunctions and costly delays. Continue reading →

Decanter centrifuges, known for their efficient separation and washing capabilities under centrifugal force, exhibit robust adaptability to various materials and are ideal for separating solid-phase particles ≥0.01mm in suspension. Their versatility has led to widespread adoption in industries such as biochemistry, fine chemicals, and pharmaceuticals. As decanter centrifuge with automatic scraper discharge and intermittent operation, they necessitate careful operation to ensure optimal performance and safety. Continue reading →

Decanter centrifuges are widely used in industrial production, and proper operation is essential to ensure efficiency, extend equipment lifespan, and minimize failures. By following the correct procedures, operators can maintain optimal performance and reduce the risk of breakdowns. Below are the key steps for operating a decanter centrifuge safely and effectively.

1. Preparation and Setup

Before starting the decanter centrifuge, it is crucial to ensure that the machine is placed on a stable, level surface and securely fixed to prevent vibrations during operation. Inspect the equipment for any visible abnormalities, loose components, or signs of wear. Once confirmed that the centrifuge is in proper condition, connect it to the appropriate power supply voltage, following the manufacturer’s guidelines.

2. Operating the Centrifuge

Once the decanter centrifuge is properly set up, install all necessary components according to the instructions. Load the material into the centrifuge chamber, ensuring it is evenly distributed to maintain balance. Close the equipment door securely, as an improperly sealed door can lead to malfunctions or safety hazards.

Set the operational parameters, including temperature, rotation speed, and runtime, according to the specific process requirements. After verifying the settings, start the centrifuge and closely monitor its operation. If any unusual noise, vibration, or irregularity occurs, stop the machine immediately and inspect the issue before continuing.

3. Shutdown and Maintenance

After the separation process is complete, shut down the centrifuge according to the recommended procedure. Wait until the machine has completely stopped before opening the door and removing the processed material.

Thoroughly clean the interior and exterior surfaces using a clean, dry cloth or a slightly damp one if necessary. Keeping the equipment clean prevents material buildup and ensures long-term efficiency. Allow the internal chamber temperature to stabilize and match room temperature before securely closing the door.

By following these correct operational procedures and performing regular inspections and maintenance, operators can optimize performance, reduce downtime, and extend the service life of the decanter centrifuge, ensuring safe and efficient processing.