
Hydrocyclones are used to separate two materials of different densities.
They operate by a mixture of material entering at the top and processing in a spiral down a conical section. The hydrodynamics inside the cyclone is extremely complex with the development of an air vortex carrying materials upwards, and also centrifugal forces separating the heavier to the edge. At the base of the unit, a spray is created with heavier phase leaving the bottom and the lighter phase being swept up.
Cyclones are operated as they are a relatively inexpensive process unit; industrial sectors for liquid / liquid cyclones include separating oil from water; starch from water and also in minerals sector in grinding circuits and other diverse sectors ranging from pulp and paper to metal working.
ITS has been involved in a wide range of research projects with hydrocyclones helping to understand process dynamics both to empirically improve performance and also to validate CFD models. A sensor can easily diagnose common fault conditions such as a blocked spigot or the developing of roping conditions (where the vortex collapses).
A further research project has developed tailored software than can accurately measure small changes in air core diameter of hydrocylones providing a basis for real-time control and optimisation.
A single ITS instrument can measure up to 8 different cyclones at the same time. Alternatively, 8 sensor planes can be installed into a single hydrocyclone to visualize its full length; this setup is depicted in the photograph below, which was taken in the ITS laboratory in Manchester UK.