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Separation technology

Herrenknecht Separation Plants are optimally tailored to the requirements and challenges of our international customers projects. During tunnelling operations, the plants continuously separate the loaded suspension (also called slurry) from the solid particles in the slurry circuit. State-of-the-art screening technology and hydrocyclones, in a powerful interplay of high G-forces and low cut points, deliver landfill or re-usable solids with low water content. The reduced muck weight also reduces disposal and recycling costs. Over time, fine particles remaining in the suspension that cannot be separated have a negative effect on important process parameters such as advance speed and daily advance rate and leads to higher wear and tear of the components. Additional equipment for the separation of fines is therefore required to prevent thickening of the slurry and to ensure efficient tunnelling over the long term. Filter presses, centrifuges or density regulation separate fines effectively. An adaptable separation plant forms the basis for successful implementation for the successful application for solid-liquid separation, for example, for the use of slurry-supported tunnelling machines such as AVN machines, Mixshields, Variable Density Machines or Vertical Shaft Sinking Machines (VSM). Separation plants optimally matched to the project’s requirements enable an ideal interaction between jacking and separation and thus maximize the jacking performance and ensure smooth operations.



Storage tanks

Modular tanks in various sizes provide the ability to store fresh water, fresh suspension, used suspension and centrate or filtrate water.



Filter presses

Filter presses, which use high pressure to filter solid particles from liquids, ensure the lowest possible disposal costs.



Centrifuges are used to separate remaining fine particles such as clay and silt from the used suspension.



Modular silos from Herrenknecht Separations offer a solution for a wide range of applications. Easy to install, flexible in use and with various accessories, they offer an ideal addition for many construction sites.


Water treatment plant

Water treatment plants enable compliance with the specified limit values of all types of wastewater occurring on the jobsite and needing to be discharged.


Booster/ circuit pump system

Centrifugal pumps convey the mixture of suspension and dissolved solids to the surface, where it can be processed.


Bentonite mixing plant

Bentonite mixing plants produce fresh suspension, which is fed into the slurry circuit in the appropriate quality and quantity.


Density Regulation System

An additional hydrocyclone stage with a finer cut point extends the service life of the suspension in the active circuit and at the same time increases the efficiency and capacity of the fine treatment.


Separation plant

The separation plant as a multi-stage separating facility separates coarse and fine-grained solid particles from the suspension in the slurry circuit, recycles the suspension for reuse and optimally treats the solid material for landfilling.


Belt conveyor system

Belt conveyor systems handle the removal of the separated solids. Collecting, elevating and slewing belt conveyors offer an optimal solution for every requirement and can be used flexibly depending on the jobsite layout and surroundings.


Control Room and laboratory

All relevant process parameters are monitored and controlled from a central control room. An integrated laboratory with equipment is available for quality control of the slurry.

Tunnel Boring Machine (TBM)

The TBM excavates soil and conveys the excavated material out of the tunnel. In slurry-supported tunnelling, the bentonite suspension supports the tunnel face in the excavation chamber, enabling a safe advance. The bentonite suspension also serves as a transport medium for the excavated soil.

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Separation Plants

Separation plants separate solid particles from suspensions in a variety of ways. Multi-stage, high-performance screening machines and hydrocyclones are used for this purpose. Efficient, reliable components specially adapted to the requirements guarantee optimum results in the entire separation process. The modular container design minimizes transport costs and installation times and ensures easy handling.

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Fine Treatment

The Density Regulation System, centrifuges and filter presses are used for fine treatment of solids-laden suspensions. This multi-stage process reduces disposal costs and significantly improves the quality of the medium to be cleaned for possible reuse. Like all Herrenknecht Separation systems, the fine treatment technologies are available in modular container form.

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Water Treatment Plants

Wastewater occurring at tunnel jobsites, such as drainage, filtration or washing water as well as rainwater, must be treated before it can be discharged into the natural environment or returned to the cycle. To meet the requirements depending on legislation and project constraints, Herrenknecht Separations has developed a modular, containerized and pre-assembled water treatment plant. The system is easy to transport, install, operate and expandable if required/necessary.

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Additional equipment

As a full-portfolio supplier, we offer total solutions for your project. In addition to bentonite mixing plants, tanks and silos, Herrenknecht Separation also supplies control rooms with laboratories, belt conveyors and other components to meet the requirements of our customers.

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All Advantages at a glance

  • Modular, expendable container design
  • Optimized adaptation to performance parameters and geology
  • Robust, durable and efficient components
  • Maximum performance in minimum space
  • Noise-reduced innovative design
  • Automated control and data management

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Our project partnership doesn't end with delivery and commissioning. We support our customers worldwide in all project phases. With professional and fast on-site service, timely supply of spare parts and our profound expertise: a smooth process is a prerequisite for best performance in your project.



Our 45 years of expertise in tunnel construction and our experience from more than 350 separation projects make us competent partners with unique overall project competence. We advise you holistically in the preliminary planning stage and throughout the entire course of the project.



With our reconditioning and refurbishment service, we offer you the possibility of having the plant professionally reconditioned after successful use by our experts in accordance with manufacturer specifications. This means proven components can be reused for subsequent projects. Our comprehensive warranty on all reconditioned products ensures uncompromising performance and safety.



As an alternative to purchase, Herrenknecht Separations also offers rental options as well as buyback options for selected components. This way, you remain flexible and your investment sums remain low. We will be happy to provide you with information about our current available offers in the rental pool.



Expertise around the globe

With global expertise from more than 350 projects in over 40 countries, Herrenknecht Separations is the leading provider of integrated engineering solutions in mechanized separation technology.






20 MIO m³


The specialists for separation

As part of the Herrenknecht Group, we develop and produce integrated solutions for the separation and recycling of solid-liquid compounds. In every phase of your project, we are at your side as a partner with our experienced team of specialists.