Category Archives: Decanter Centrifuge

What are the frequently asked questions about decanter centrifuge?

　　 Decanter centrifuge is a kind of centrifuge. It is a kind of mud-water mixture that enters the drum through the feed pipe and the screw discharge port. Under the action of the centrifugal force generated by the high-speed rotation of the main engine, the solid particles with larger specific gravity are deposited on the inner wall of the drum, and the spiral blades moving relative to the drum successively scrape the solid particles deposited on the inner wall of the drum and push them out. The slag outlet, the separated clear liquid flows out of the drum machine through the opening of the weir plate.

1. What are the main components of the screw conveyor in the decanter centrifuge?

The screw conveyor of the Decanter centrifuge contains two parts: the drum and the screw, and the screw includes the cylinder and the pusher blade. On the cylinder, there is a feed end and a clear liquid outlet end, which are used to feed materials and flow out the clear liquid after separation.

2. Why can the Decanter centrifuge be used in petrochemical and waste treatment?

Because the decanter centrfuge has the characteristics of compact structure, low energy consumption, strong production capacity, and good adaptability to materials. And with the continuous development of science and technology, the centrifuge has been greatly improved and advanced in terms of structure, performance and technical parameters, and its separation effect has also been improved, so it is used in petrochemical and The treatment of the three wastes is very suitable.

3. Can the decanter centrifuge be used as the main engine of sludge dewatering?

If it is used for sludge dewatering, it is very suitable, and if it has a large aspect ratio and a fully enclosed operation is selected, then it can have a good use effect, because its It has advantages that other sludge dewatering equipment does not have.

4. What is the process of desilting using a decanter centrifuge in a sewage treatment plant?

In the wastewater treatment plant, in the treatment of activated sludge, the whole process of using a decanter centrifuge to desludge is to drive the high-speed rotation of the sludge through a high-speed rotating drum, and then generate centrifugal force to make the sludge The sedimentation of the solid particles accelerates and concentrates on the wall of the drum. Then, through the spiral, the formed mud cake is scraped to the small end of the rotating drum, so that it can be discharged, thereby completing the desliming work.

5. What is the main use of the decanter centrifuge? In addition, what are the unloading conditions of the decanter centrifuge?

Decanter centrifuge is mainly used to remove impurities and suspended solids in the liquid to achieve the role of purification. The general decanter centrifuge, its discharge conditions, mainly including cone angle and bowl speed.

Bearing Replacement Method for Decanter Centrifuge

During operation, a Decanter centrifuge runs at high rotational speeds, which places stringent demands on its bearings. Proper bearing maintenance and replacement are crucial to ensure smooth operation, prevent damage, and extend service life of the Decanter centrifuge.
When the drum bearings show signs of wear or malfunction and require replacement, it is essential to follow the correct procedure. The following steps outline the recommended bearing replacement method to ensure safe and reliable operation.

1. Preparation and Safety

Before starting, ensure the following:

Only qualified personnel should perform disassembly and assembly.

Use professional tools designed for bearing and centrifuge maintenance.

Disconnect the centrifuge from power and follow all lockout/tagout procedures.

Clean the working area and prepare lifting devices for the Decanter centrifuge if needed.

2. Disassembling the Small-End Bearing

Remove the Pressure Plate Bolts
Begin by loosening and removing the bolts from the pressure plate located on the main pulley end.

Extract the Pressure Plate
Use jack screws to evenly push out the end pressure plate. Ensure that all screws are loaded evenly to avoid skewing or deformation.

Remove the Pulley
Using a three-jaw puller, grip the pulley and pull it out carefully.

Mark Components for Reassembly
Clearly mark the relative positions of all components (keys, sleeves, seals, etc.) to ensure correct reinstallation later.

Remove Associated Components
Sequentially disassemble the flat key, taper-end screw, bearing seat sealing ring, and O-ring.

Extract the Bearing Assembly
Place a supporting pad on the bearing end face of the bowl shaft. Then, using a puller tripod, simultaneously remove the bearing sleeve, bearing sleeve gland, bearing, and shaft sleeve as a single unit.

3. Disassembling the Big-End Bearing

The process for the big-end bearing is similar but involves additional components:

Remove the Flange Bolts
Loosen and remove the flange bolts, then take out the differential and spline shaft.

Disassemble the Shaft End Pressure Plate
Remove the bolts from the shaft end pressure plate and use jack screws to push it out evenly. Keep the applied force balanced to avoid tilting.

Remove the Bearing Assembly
Place a pad on the shaft end face, then use a three-jaw puller to remove the connecting flange, bearing seat sealing ring, and flat key.

Extract Bearing Components
As with the small end, use a tripod puller to remove the bearing sleeve, bearing sleeve gland, bearing, and shaft sleeve together.
Make clear alignment marks on the bearing sleeve for accurate reassembly.

4. Key Notes for Reassembly

Ensure all parts are thoroughly cleaned and inspected for wear or damage before reinstallation.

Apply appropriate grease or lubricant to the bearings and seals according to manufacturer specifications.

Install the components in the reverse order of disassembly, aligning all marks made earlier.

After assembly, perform a manual rotation check to confirm smooth movement before restarting the centrifuge.

5. Summary

Although the replacement procedures for the small and big end bearings are similar, careful attention to detail is essential throughout the process. Accurate marking, even force application, and the use of correct tools will ensure safe bearing replacement and help maintain the reliability and longevity of the Decanter centrifuge.

The Role of Decanter Centrifuges in Mining Tailings Dewatering

Mining operations produce enormous volumes of tailings — a slurry composed of fine solids, water, and residual minerals — that must be properly treated before reuse or disposal. Traditional tailings ponds and dams are facing increasing challenges, from limited space to stricter environmental regulations. In this context, decanter centrifuges are transforming tailings management by enabling rapid, efficient solid-liquid separation with minimal environmental impact.

GNLW764: Engineered for Large-Scale Mining Applications

The GNLW764 Decanter Centrifuge, GN Separation’s largest and most powerful model, is specifically designed for large-scale operations such as mining tailings dewatering and TBM slurry treatment. Featuring a 30-inch (764 mm) bowl and heavy-duty construction, it delivers high throughput and reliable performance under demanding conditions. To withstand abrasive slurries, critical wear zones — including the screw conveyor blades and solids discharge ports — are protected with tungsten carbide coatings, ensuring exceptional durability, reduced maintenance, and long service life.

The centrifuge is also equipped with a Variable Frequency Drive (VFD) control cabinet, allowing precise adjustment of rotational speed to suit different materials. Real-time monitoring of vibration and temperature enhances operational safety and ensures stable, efficient performance.

Optimized Dewatering with the GNSJY6000 Flocculation Unit

For even better separation results, GN recommends integrating the GNLW764 with its GNSJY6000 Flocculation Dosing Unit. This automated system accurately injects flocculants into the slurry, causing fine particles to bind into larger clusters that separate more easily. The combined setup boosts solids recovery, increases water clarity, and reduces overall processing costs.

In summary, the GNLW764 Decanter Centrifuge represents a powerful, sustainable solution for modern mining operations. By combining advanced materials, intelligent control, and complementary flocculation technology, it helps operators achieve efficient, eco-friendly, and cost-effective tailings management.

With the GNLW764 Decanter Centrifuges now ready for dispatch, GN Separation is poised to strengthen its position as a professional solution provider in industrial separation technologies, delivering value to clients and contributing to a more sustainable future for the mining industry.

Key Precautions When Operating a Centrifuge

Centrifuges play a vital role in industries such as chemical processing, pharmaceuticals, food, and mining by separating solids and liquids efficiently. However, improper use can lead to equipment damage, poor separation performance, or even safety hazards. Below are several essential points to consider when operating a centrifuge.

T1-Dewatering Centrifuge

1. Balance and Loading Are Critical

One of the most common causes of vibration and mechanical failure in a centrifuge is unbalanced loading. Before starting the machine, ensure that all containers, tubes, or feed compartments are loaded symmetrically and evenly. In batch-type centrifuges, equal mass on opposite sides of the rotor prevents excessive stress on the bearings and drive system. For continuous decanter or disc centrifuges, steady feed flow is key—sudden surges can upset the balance and cause wear. Always check that covers are properly closed and that no foreign objects are inside the bowl before operation.

2. Monitor Operating Parameters and Maintenance

Centrifuges operate under high rotational speeds and generate significant centrifugal forces. Operators should regularly monitor parameters such as rotational speed (RPM), feed rate, vibration level, and bearing temperature. Exceeding the recommended speed or operating with a worn bearing may lead to mechanical failure.
Routine maintenance is equally important—inspect seals, belts, and lubrication systems frequently. Scheduled replacement of consumable parts such as gaskets and bearings helps maintain separation efficiency and prolong service life. Following the manufacturer’s maintenance intervals ensures stable operation and prevents costly downtime.

3. Prioritize Safety and Training

Because centrifuges involve high-speed rotation, safety precautions are non-negotiable. Operators should be trained on emergency shutdown procedures and aware of the specific materials being processed—some slurries or chemicals may create explosive or corrosive conditions. Always keep safety guards in place, avoid opening covers while the bowl is still spinning, and wear appropriate personal protective equipment (PPE). In addition, it’s good practice to record operating data and perform vibration analysis periodically to detect early signs of imbalance or mechanical fatigue.

Conclusion

Proper operation and maintenance of a centrifuge not only enhance performance but also ensure safety and reliability. By balancing loads carefully, monitoring key parameters, and maintaining strict safety discipline, operators can maximize uptime, extend equipment lifespan, and achieve consistent separation results in any industrial process.

GN Decanter Centrifuges: Efficient Solutions for Drilling Waste Management and Oil Mud Recovery

Oil-based mud (OBM) and water-based mud (WBM) are essential in modern drilling operations, providing wellbore stability, cooling, and lubrication for drill bits. However, the handling of drilling cuttings and oil-contaminated sludge poses significant environmental and operational challenges. Improper disposal can lead to soil and water contamination, regulatory non-compliance, and increased waste management costs.

In this context, GN Decanter Centrifuges, along with our oil mud recovery systems, have become indispensable equipment for the drilling and oilfield services industry. These machines utilize high-speed rotational separation to efficiently divide solids, liquids, and oil components based on density differences. As drilling fluids circulate, cuttings and fine solids are continuously separated from the base mud, allowing for both waste minimization and mud recycling.

Fig. 1 Drilling mud treatment system

The working principle of GN decanter centrifuges is straightforward yet highly effective: the slurry enters a rotating bowl, where centrifugal force drives solids toward the bowl wall. A conveyor screw, rotating at a slightly different speed, continuously transports the solids to the discharge port, while the clarified liquid flows out separately. Integrated into GN’s oil mud recovery systems, these centrifuges enable the recovery of valuable drilling oil from cuttings, reducing environmental impact and reclaiming reusable oil for mud preparation.

For water-based mud, GN decanter centrifuges efficiently remove fine solids to maintain mud viscosity, improve drilling efficiency, and protect downstream equipment. By combining high-precision decanter centrifuges with our automated recovery system, operators can achieve stable mud properties, minimal waste, and regulatory compliance.

With increasing environmental regulations and the industry’s focus on sustainability, GN decanter centrifuges and oil mud recovery solutions are no longer optional—they are a core component of responsible drilling operations. Modern systems offer adjustable bowl speeds, differential control, and durable stainless-steel construction, ensuring long-term reliability, high separation efficiency, and reduced maintenance requirements.

In summary, GN decanter centrifuges and oil mud recovery systems play a critical role in drilling waste management, helping operators reduce environmental impact, recover valuable oil, and maximize the reuse of drilling fluids, making them essential for both efficient production and sustainable operations.

Principle and Function of Three-Phase Decanter Centrifuge

A horizontal spiral sedimentation centrifuge, commonly known as a decanter centrifuge, is an efficient piece of centrifugal separation equipment designed for continuous solid-liquid or liquid-liquid-solid separation. Based on structure and function, decanter centrifuges can be divided into horizontal spiral filter centrifuges and horizontal spiral sedimentation centrifuges. Continue reading →

The Importance of Dynamic Balancing in Decanter Centrifuge Manufacturing

Dynamic balancing is a crucial step in the manufacturing of a decanter centrifuge, directly determining its stability, performance, and lifespan. Because a centrifuge operates at extremely high rotational speeds, even a tiny imbalance in the rotating assembly can lead to serious vibration, noise, premature bearing wear, or even structural damage.

At GN Separation, every decanter centrifuge goes through a three-stage dynamic balancing process to ensure excellent performance and long-term reliability.

  1. First Stage – Medium-Speed Balancing (around 1800 RPM):
    In this stage, both the bowl and scroll assemblies are tested at medium speed to eliminate initial imbalance and ensure that the components are stable before high-speed rotation. This helps technicians identify any unbalance caused by machining or assembly tolerances early on.
  2. Second Stage – High-Speed Balancing (Operating Speed):
    The next step involves balancing the rotating assembly at the centrifuge’s actual working speed, which can exceed 3,000 RPM depending on the model. This high-speed test simulates real working conditions and detects even the smallest residual imbalance that only appears at high rotational speeds.
  3. Third Stage – Complete Machine Balancing:
    Finally, after the whole centrifuge is fully assembled, the entire unit undergoes integrated dynamic balancing in GN’s dedicated balancing workshop. This final step ensures the centrifuge runs smoothly and stably under full-speed operation, minimizing vibration and extending the life of bearings and seals.

Figure 1. Dynamic Balancing

Many manufacturers only perform low-speed or single-stage balancing, but GN’s three-stage balancing process provides a much higher level of accuracy and safety. During each stage, vibration amplitude and phase angle are carefully measured, and corrections are made until the unit meets strict balance standards.

Through this comprehensive process, GN ensures that every centrifuge operates with minimal vibration, lower noise, and maximum reliability. Dynamic balancing is not just a quality checkpoint — it’s a core guarantee of precision engineering and long-lasting performance.

Efficient Mud Management: Advanced Dewatering System for U.S. Construction Projects

1. Background: The Challenge of Construction Mud Disposal

In large-scale construction projects, especially in urban areas of the United States, managing slurry and drilling mud is a major environmental and operational challenge. Construction mud typically contains fine solids, sand, silt, and chemical additives that make it difficult to dispose of directly. Traditional settling tanks are inefficient and require large space, while uncontrolled discharge can lead to pollution and penalties. To achieve cleaner operations and meet strict environmental standards, advanced solid-liquid separation technology has become an essential part of construction site management.

2. The Dewatering Solution: Vibrating Screen and Decanter Centrifuge Combination

The combination of a dewatering vibrating screen and a big bowl decanter centrifuge provides an efficient and compact solution for mud treatment. The vibrating screen performs the first-stage separation by removing coarse particles and sand from the slurry. This reduces the solids loading on subsequent equipment. The partially clarified liquid then enters the decanter centrifuge, which uses high rotational speed and strong centrifugal force to separate fine solids and recover clean water.

The big bowl decanter centrifuge, featuring a large diameter and optimized bowl length ratio, delivers higher capacity and drier solids discharge. It ensures continuous operation with automatic control and minimal operator intervention. Together, this system significantly reduces waste volume, lowers disposal costs, and allows water to be recycled for reuse in drilling or construction processes.

3. Environmental and Economic Benefits

By adopting this dual-stage dewatering system, construction contractors can achieve sustainable operations while improving profitability. The recovered water can be reused onsite, reducing fresh water consumption by up to 80%. The dry solids can be easily transported for landfill or further treatment, minimizing handling costs.

Moreover, the entire process is enclosed and automated, ensuring clean, safe, and compliant site management. With increasing emphasis on green construction and circular resource use, integrating vibrating screens and big bowl decanter centrifuges has become a preferred choice for many U.S. engineering and infrastructure projects.

Hydrovac Slurry Separation System for America Client

In modern construction and utility installation projects—such as hydrovac excavation and horizontal directional drilling (HDD)—efficiently managing slurry waste is essential for both operational productivity and environmental responsibility. GN Separation specializes in the design and manufacture of advanced waste management systems engineered specifically for hydrovac slurry and directional drill mud treatment. Continue reading →