Hybrid screw

Another quantum leap in the development of screw pumps! The innovation that transforms screw pumps into genuine “heat pumps”!

“Hybrid screw”

Many well-known advantages – new benefit:

All over the world, there are more 50,000 different screw pumps for various applications such as lifting equipment, polder pumps or return sludge pumps.

The key arguments in favor of the screw pumps have been well-known for a long time:

• High degree of efficiency up to 80%
• Long service life of 20–25 years
• Unbeatable operational reliability, especially with different wastewater coarse material
• Very flexible in terms of feed rate
• Dry run protection
• Self-regulating

What’s new?

We use the screw trough as a large-area heat exchanger. The excellent properties of such a heat exchanger become evident upon looking at the physical characteristics:

• Superior heat transfer through turbulent flows with high Reynold numbers at the wetted perimeter
• Steel-made heat exchanger with excellent thermal conductivity
• Rotary motion leads to considerably larger wetted surface areas than in the channel
• Deposit-free contact area
• Permanently self-cleaning and maintenance-free – for decades!
• No impact on the conveying process
• Visible and accessible any time

The process:

By integrating water-bearing channels, the steel trough of the screw pump becomes a heat exchanger. Within this secondary circuit, water is conducted along the rear side of the trough. The water takes up waste heat and transports it to a customary heat pump where the temperature level is increased and supplied to the consumer.

What makes this process so special is that the transporting function of the screw is not impaired; on the contrary – it improves the conveying process.

High savings potential for municipal and industrial clients!

So far, the utilization of fossil (heat) energy for the production of electricity and the transformation of electricity into heat involves enormous losses, far higher than 50%. Regenerative energy sources, such as wind energy, first convert the kinetic energy of the rotors into electricity and then electricity into heat. The direct use of waste heat therefore seems far more sensible. Possible applications are: heating of buildings, low-temperature sludge drying, recovery of process heat, etc.

Screw refurbishment becomes a stroke of genius!

Thousands of pumps installed since the 1960s will have to be refurbished in the years to come. Especially the previously used cast-in-place concrete troughs are nearly always worn out, making refurbishment necessary. In this context, the trough is easily equipped with a heat exchanger; extra costs compared to a conventional steel trough are reasonable. Even if the use of thermal energy does not yet seem possible, the advanced refurbishment provides the opportunity for future applications.

This way, you as a customer benefit twice:
A refurbished screw with maximum thermal potential!

Where can you get the „hybrid screw”? At KUHN GmbH — of course !

In addition to our expert knowledge in water-conveying screws, we also manufacture screens and screenings treatment equipment.
We also supply complete plants and can look back on decades of experience in meeting the highest standards in:

• installation, assembly and service
• process measurement and control
• renewable energy
• heat pump technology

… and everything at the highest level!

Produced in Germany and installed by our partners throughout the world!

Made in Germany quality, experienced specialists, only the highest grade components:

Contact us now for more information!


German Water Partnership

We are member

KUHN ist Mitglied der Deutschen Vereinigung für Wasserwirtschaft, Abwasser und Abfall (DWA)