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Pumps and Cyclones

Solid/liquid separation – Simply precise

Hydrocyclones – Ideal for Separating Solids


Flexible systems are needed for the preparation and processing of sand and gravel for the building materials industry. Firstly, in order to meet the respective requirements. And secondly, to satisfy the current guidelines, e.g., on water recovery. The choice of systems for sand and gravel processing
or for water recovery will be primarily motivated by the

Besides the fractions, the deployment sites and operating conditions will be
the decisive factors for the respective choice of a system. Hydrocyclones are deployed on a standalone basis or as part of a complete system for sand and gravel processing. They likewise play a key role in water recovery at gravel plants.
Naturally, STICHWEH hydrocyclones are deployed with the appropriate pumps. These deliver the material that has to be classified/separated, along with the necessary inlet pressure, to the hydrocyclone.

The delivery times at the manufacturer for the spare parts for these pumps are extremely long.
STICHWEH is the only company that is able to supply the main wear parts for this pump range from its stock (subject to prior sale).


Hydrocyclones are deployed for the processing of sand and gravel on a standalone basis or in combination with bucket wheels, screening machines and jigs.

For example, combi A) bucket wheel and hydrocyclone
The bucket wheel is used to dewater and discharge the coarse sand. Subsequently, a cyclone is used to separate particles from the waste water from the bucket wheel, or from partial amounts of the waste water.
Only small quantities of mixtures or solids are fed into the cyclone. This has a favourable effect on the wear and tear and the energy requirements of the pump (a unit within the cyclone).
For example, combi B) screening machine and hydrocyclone
During the washing and screening process, on the last screen deck, you get a mixture of water and sand. If it is not possible to separate this by means of a bucket wheel then here we would recommend using a cyclone. The cyclone separates recoverable solids from the water and discharges these. The waste water from the cyclone is then drained on site.

Hydrocyclones are likewise deployed for water recovery.
To enable gravel plant operators to purify their wash water and to feed the clear water back into their washing cycles, for the purpose of recovering the fine sand, STICHWEH is able to provide fine sand bucket wheels and hydrocyclones – individually or in combination – customised according to the requirements.

Both pieces of equipment thus carry out an important preliminary stage for waste water treatment systems. Since these work most effectively if the smallest sand particles have been removed in advance, too.

Hydrocyclones are centrifugal separators/are machines for classifying

The material (water/solids mixture) is fed into the cyclone sideways (tangential inlet) and under pressure.
The pressure as well as the tangential inlet cause the mixture to develop a rotational movement. Through the action of the centrifugal force the solids slide down the walls of the cyclone to the underflow for removal.
A vortex is created in the centre of the rotating fluid that allows the fluid together with any non-separable materials to be discharged through the overflow pipe. A defined separating cut is achieved through the conceptual design of the system.


  • Precision classification in the fine and finest grain size ranges
  • Recovery of usable raw materials from the waste water of preparation plants
  • Lower space requirement and low weight – suitable for integration into buildings
  • Advantages with respect to the separating cut – separating cuts of up to 10 µ can be achieved with cyclones


STICHWEH Pumps and Cyclones Factsheet