What is a Hydrocyclone?

A hydrocyclone is a device used for the classification of sub sieve materials typically below 200 microns. The material (in slurry form) is fed into the feed chamber at pressure, using a centrifugal pump. The centrifugal pump is paired with a cyclone to ensure optimal feed rate for the cyclone to perform efficiently.


Fluid Flow and Particle Motion
















Pressure Within the Hydrocyclone 

Due to the conical shape of the cyclone, as the material makes its way down the cone, the pressure increase creating a vortex within the centre of the cyclone capable of lifting particles caught within it, carrying them up through the overflow of the cyclone


How the Separation Occurs

The hydrocyclone separates the solid particles due to their relative settling rate. The separation of the solid particles occurs due to centrifugal force which is created within the body of the cyclone. As the material is fed in tangentially, the solid particles are accelerated against the walls of the cyclone. The force within the hydrocyclone acts greatest on the largest particles and are forced against the wall of the cyclone. The smaller finer particles find themselves drawn towards the centre of the cyclone. The finer particles in the centre of the cyclone are caught in the vortex and carried up through the overflow, allowing the coarser particles to continue falling and eventually leaving through the underflow.


Pump Requirements

Gromatex hydrocyclones can be paired with any brand of centrifugal slurry pump, however care must be taken to ensure that the pump feed rates and operation pressures are optimal with the cyclones requirements to ensure optimal operating conditions and maximum efficiency. Gromatex recommend using SlurryPro’s centrifugal pump range. We can specify and supply pumps according to your specific requirements. As a rule the tables below indicate typical pairings.
Single Pump / Single Cyclone Setup
Single Pump / Double Cyclone Setup






Operating Variables

During the operation of the hydrocyclone there are certain variables that will change and can affect the performance of the cyclone. The two main variables to be concerned about are feed solids concentration and feed pressure.


Hydrocyclone Variables 

Certain parts within the assembly of the cyclone can be altered to change or tune the properties of the cyclone. Cut points can be managed by changing the inlet diameter, the vortex finder and most easily the spigot assembly. Gromatex carry a fully range of spigots and vortex finder which are available upon request.