2
situations, the performance of industrial scale hydrocy-
clones is mostly compromised [8–9] .
An attempt has, therefore, been made in this article to
demonstrate the theoretical approach to solve the Rankine
vortex equation to quantify the flow and pressure varia-
tions. A series of experiments were conducted using Weir’s
Cavex ® hydrocyclone where process variables, such as solids
concentration and feed flowrate, are experimentally studied
to determine the key classification parameters. From the
present theoretical paradigm, we estimate the centrifugal
force intensity (u2⁄Rg) and correlate it with performance
parameters, like split factor and separation cut size (d50c).
For validation of the current approach, we used the same
process variables to derive the design parameter and com-
pared this parameter with the existing design. The current
approach can provide good insights towards the selection
of the design parameters and can be useful for an industrial
professional to optimize the different operating parameters
of the hydrocyclone to achieve the best performance.
MATERIALS AND METHOD
The tests were conducted on a pilot scale, feeding the
Cavex® hydrocyclone with silica sand with solids density
of 2.65 t/m3. The details of hydrocyclone geometry used
for pilot scale testing are shown in Table 1. Figure 1 shows
the particle size distribution of the silica sand sample with
an F80 of 60 microns on average. The pilot scale test setup
consisted of a pump-sump assembly in a closed loop cir-
cuit attached with a Cavex ® 100CVX hydrocyclone. The
required pressure to obtain a good performance in the
hydrocyclones depends upon the cyclone size and of the
process conditions. The testing was performed at three
pressure levels (68.9 kPa, 103.4 kPa and 137.9 kPa). A
variable frequency drive (VFD) was connected with the
slurry pump, allowing for the maintenance of the target
operating pressure and flowrate. For each operating condi-
tion, samples of hydrocyclone feed, overflow and underflow
were obtained during the testing. The samples were ana-
lyzed for solids concentration and particle size distribution.
Mass flow of solids and water at the feed was back calcu-
lated from the measured mass of overflow and underflow
samples.
THEORETICAL MODELING
In-depth review of the inherent flow field inside a
hydrocyclone reveals the existence of a force- vortex flow
near the central region and free-vortex flow otherwise
[10–11]. The swirling flow in a hydrocyclone creates an air
core along the axis, normally connected to the atmosphere
Figure 1. Feed size distribution for silica sand sample
Table 1. Cavex® hydrocyclone geometry used for pilot scale
testing
Parameter Dimension
Hydrocyclone diameter (mm) 100
Inlet diameter (mm) 40
Vortex finder diameter (mm) 35
Spigot diameter (mm) 17.5
Cone angle 6o
situations, the performance of industrial scale hydrocy-
clones is mostly compromised [8–9] .
An attempt has, therefore, been made in this article to
demonstrate the theoretical approach to solve the Rankine
vortex equation to quantify the flow and pressure varia-
tions. A series of experiments were conducted using Weir’s
Cavex ® hydrocyclone where process variables, such as solids
concentration and feed flowrate, are experimentally studied
to determine the key classification parameters. From the
present theoretical paradigm, we estimate the centrifugal
force intensity (u2⁄Rg) and correlate it with performance
parameters, like split factor and separation cut size (d50c).
For validation of the current approach, we used the same
process variables to derive the design parameter and com-
pared this parameter with the existing design. The current
approach can provide good insights towards the selection
of the design parameters and can be useful for an industrial
professional to optimize the different operating parameters
of the hydrocyclone to achieve the best performance.
MATERIALS AND METHOD
The tests were conducted on a pilot scale, feeding the
Cavex® hydrocyclone with silica sand with solids density
of 2.65 t/m3. The details of hydrocyclone geometry used
for pilot scale testing are shown in Table 1. Figure 1 shows
the particle size distribution of the silica sand sample with
an F80 of 60 microns on average. The pilot scale test setup
consisted of a pump-sump assembly in a closed loop cir-
cuit attached with a Cavex ® 100CVX hydrocyclone. The
required pressure to obtain a good performance in the
hydrocyclones depends upon the cyclone size and of the
process conditions. The testing was performed at three
pressure levels (68.9 kPa, 103.4 kPa and 137.9 kPa). A
variable frequency drive (VFD) was connected with the
slurry pump, allowing for the maintenance of the target
operating pressure and flowrate. For each operating condi-
tion, samples of hydrocyclone feed, overflow and underflow
were obtained during the testing. The samples were ana-
lyzed for solids concentration and particle size distribution.
Mass flow of solids and water at the feed was back calcu-
lated from the measured mass of overflow and underflow
samples.
THEORETICAL MODELING
In-depth review of the inherent flow field inside a
hydrocyclone reveals the existence of a force- vortex flow
near the central region and free-vortex flow otherwise
[10–11]. The swirling flow in a hydrocyclone creates an air
core along the axis, normally connected to the atmosphere
Figure 1. Feed size distribution for silica sand sample
Table 1. Cavex® hydrocyclone geometry used for pilot scale
testing
Parameter Dimension
Hydrocyclone diameter (mm) 100
Inlet diameter (mm) 40
Vortex finder diameter (mm) 35
Spigot diameter (mm) 17.5
Cone angle 6o