The Flottweg C-series accelerates the supplied separation medium particularly effectively, thus saving energy. The solids are thrown onto the inner wall of the bowl by acceleration and discharged via the decanter scroll to the conical bowl end.

In contrast to other decanter centrifuges, the C-series decanter have a double cone and a baffle plate. The double cone reduces the distance between decanter bowl and scroll. This presses the solids against the baffle plate and increases the pressing effect. The separated water flows away without pressure along the screw.

HTS = Highest dry solids content

The centrifuge for dewatering sewage sludge

The Flottweg HTS Decanter® is a specialized machine for drying out sewage sludge, which is the solid material left over from treating wastewater. "Dry solids content" refers to the amount of solid material remaining after most of the water has been removed. This decanter is known for its high performance, using less energy and fewer additives to achieve better results. Compared to traditional methods, the HTS Decanter® increases the amount of dry material, which can lead to an 80% reduction in sludge volume and save about 8% in disposal costs. It's a highly automated system, which means it can adjust to changes in the sludge and continue to operate with minimal manual intervention, making it a cost-effective solution for wastewater facilities.

OSE = optimum sludge thickening

The decanter centrifuge for the thickening of sewage sludge

In the process of treating waste water, fine biological sludge is constantly produced during the decomposition process at a sewage treatment plant. For a stable decomposition process in the biological treatment phase, the sludge produced in the secondary sedimentation pond, also known as excess sludge, is removed and fed into the digestion tower. Flottweg's OSE decanters thicken the sludge before it enters the digestion tower. Sewage treatment plants benefit from an even feeding of the digestion tower and can thus optimally use the volume of the digestion tower. The Flottweg OSE decanter is specially designed for sludge thickening. Thus this thickening centrifuge achieves considerably better separation qualities than other centrifuges.

More than 50 years of experience and know-how in the field of sewage sludge thickening flow into our Flottweg OSE decanters. The thickening decanter is thus convincing in terms of reliability, high economy and minimum maintenance.

Flottweg has developed a unique centrifuge concept specifically for high-degree dewatering of sewage sludge: the Flottweg X Series.

The Flottweg Xelletor System Redefines State of the Art

• Maximum compression and separation efficiency, thanks to a super-deep pond and baffle plate.

• Flottweg Recuvane® for the recovery of the energy used.

• The powerful in-house design of the Flottweg Simp Drive®.

• Shields surroundings well from odors and sewage sludge aerosols, thanks to sealed construction.

• Fully automated regulation of bowl and differential speed; automatic flocculant dosing with real-time monitoring on request.

Flottweg X Series: the Most Economical Solution for Your Sewage Sludge Dewatering

• Xtra dewatering performance: Up to 10%* less sludge volume due to up to 2% higher total dry solids in dewatered sludge.

• Xtra polymer savings: Up to 20%* less flocculant needed.

• Xtra energy savings: Up to 20%* lower energy consumption.

• Xtra clean: The separation degree is greater than 99%.

• Xtra capacity: Up to 15%* more throughflow.

^{* in comparison with our centrifuges in the C Series}

The High-Performance Decanters of the Flottweg Z Series for Two-Phase or Three-Phase Separation

As truly modular centrifuges, they are available both as two-phase decanters or as Tricanters® (three-phase decanters).

For every process, the centrifuges used require a different capacity. Thus, our Z Series decanter centrifuges are available in a wide variety of sizes. They can be modularly adapted to specific separation tasks.

Our Flottweg Z Series High-Performance Decanters: Maximum Optimization and Automation

• Maintenance-friendly design ensures minimum downtime.

• Optimum separation results and energy recovery, due to optimized bowl and scroll geometry

• Complete wear protection, high-quality stainless steel, use of high-quality bearings, and a robust design for long service life

• Space-saving installation

• Automated operation possible

Thanks to Modular Design, the Right Decanter Centrifuge for Every Application

Hygienic Variant

In particular when processing foods, it is essential that all process components meet hygienic standards. The cleanliness of decanter centrifuges plays a decisive role in the food industry. The product-wetted parts of our hygienic Flottweg decanters have a minimum of hard-to-clean places. The welding seams are also hygienically ground. Spray nozzles are provided in the bowl, the solids discharge and the rotor. These permit the complete cleaning of product-wetted parts – without first disassembling the machine.

ATEX Variant

ATEX – Atmosphère Explosible – is a directive of the European Union for the plants and machines used in areas at risk of explosion. It applies when explosive mixtures are present in the environment or they are processed in the decanter.. To prevent an explosion (ignition source prevention) or the creation of an explosive atmosphere in the decanter, it must have protective measures. Flottweg decanters meet the required directive for safe operation in Zones 1 and 2.

Pond Depth

Pond depth determines the time liquid stays in the decanter bowl. Depending on the application and separation results, different pond depths can be used.

Shallow pond: The liquid layer in the centrifuge is thin. As a result, the clarifying zone is comparatively short. This reduces clarification performance while simultaneously improving the dry substance of the discharged solids.

Deep pond: The liquid layer in the centrifuge increases. This extends the clarifying zone and improves clarification performance. At the same time, the dry section is shortened, so the solids discharged are wetter.

For optimum pond depth, Flottweg draws on its entire know-how from more than 60 years of experience in solid/liquid separation.

Centrifuge Drive Systems

To accelerate the medium to be separated, the bowl must rotate at high speed. At the same time, the decanter scroll must rotate at a low speed differential with high torque.

This challenge is mastered optimally by all Flottweg drives. Depending on the process and fluctuations in incoming mixture, we offer different drive systems.

The Flottweg Simp Drive®'s drive permits the bowl and differential speed to be adjusted individually. With an optimum price/performance ratio and a broad application spectrum, it is suitable for demanding separation tasks with variable feed concentrations.

In the classic separation process, solids are separated from a liquid, or two liquids of different densities are separated. But often both come together. This is exactly where the Tricanter^® from Flottweg is the right solution. It allows the continuous separation of three phases (solid-liquid-liquid) in a single process. This is attractive, for example, in the treatment of oily sludges, in starch production and in fat recovery.

More than 40 years ago, Flottweg developed the Tricanter^® to separate three phases in a single simultaneous process. The prerequisites for this are that the liquids are not soluble in each other, that they have different densities and that the solids phase has the highest specific weight. On this basis, the specially designed impeller system produces optimum separation results.

Three-phase separation offers users several advantages: The combination of the processing steps eliminates the need for additional separation stages, which results in considerable cost savings. In addition to its high selectivity, the Tricanter^® is particularly attractive because of its versatility. It can adapt to changing inlet conditions at any time. In addition, there are the proven engineering and Flottweg services, from application-oriented project planning, through commissioning, to maintenance and spare parts supply. Thus, users benefit in the long term from the highest quality "Made in Germany."

How the Flottweg Tricanter® works

The design and function of the Flottweg 3-phase centrifuge is similar to that of a decanter (two-phase separation). Solids settle on the inner wall of the bowl when subjected to centrifugal force. The scroll constitutes the conveying tool. Under centrifugal force, solids settle on the inner wall of the bowl.

The decisive difference to the decanter lies in the separate expulsion of the two liquid phases: With the Tricanter^®, the heavy liquid is discharged under pressure via an adjustable impeller. The light liquid flows off without pressure. The impeller allows infinite adjustment of the pond depth during operation and thus fast, precise adaptation to changing feed conditions - without interrupting operation.