Penjelasan Mengenai Cyclone SeparatorDeskripsi lengkap
Descripción completa
Deskripsi lengkap
Cyclone DesignFull description
cycloneDeskripsi lengkap
soal dan penyelesaian design cycloneFull description
Full description
Cyclone Design
ddddddFull description
contoh perhitungan cycloneDeskripsi lengkap
contoh perhitungan cycloneFull description
aDeskripsi lengkap
Cyclone Separator Press Drop
Deskripsi lengkap
Tính Toán CycloneFull description
Description complète
Full description
Hydrocyclones
Hydrocyclones
1.
Cyclone Operating Variables
2.
Efficiency Curves
3.
Nageswararao Model
4.
Fish Hook Effect
5.
Density Effects
6.
Fitting the Model
7.
Limitations of the Model
Hydrocyclones
1.
Cyclone Operating Variables
2.
Efficiency Curves
3.
Nageswararao Model
4.
Fish Hook Effect
5.
Density Effects
6.
Fitting the Model
7.
Limitations of the Model
Hyd ydro rocy cycl clon one e Term rmin inol olog ogy y
Feed inlet
Vortex finder Feed chamber Cylindrical section
Conical section
Ape A pe x
Hydroc ydrocyclon yclone e Flow Patte tterns rns Overflow
Feed
Outer flow spiral (downwards)
Inner flow spiral (upwards)
Underflow
Forces on Particles
Centrifugal
Drag
Gravity
Separation Variables Particle Properties
size
shape
s.g.
Separation Variables Fluid Properties
density
solids present
viscosity
Separation Variables Machine Properties
inlet area
diameter
cylinder length
cone angle
vortex finder diameter
spigot diameter
vortex finder length
angle of inclination
Efficiency Curves - I 1.0 0.9 0.8 e s r a o C o t n o i t c a r F
Actual Efficiency Curve
0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0.01
0.10
1.00 Size (mm)
10.00
Efficiency Curves - II 1.0 0.9 Actual
0.8 e s r a o C o t n o i t c a r F
0.7 0.6 0.5
Water Split
0.4 0.3 0.2 0.1 0.0 0.01
0.10 D50 Act
1.00 Size (mm)
10.00
Short Circuit Model Feed
Short
True
Circuit
Classification
Coarse
Remainder
Product
Fine Product
Efficiency Curves - III 1.0 0.9 Ac tu al
0.8 e s r a o C o t n o i t c a r F
Corrected
0.7 0.6 0.5 0.4 0.3 0.2
D50 Corr
0.1 0.0 0.01
0.10 D50 Act
1.00 Size (mm)
10.00
Efficiency Curves - IV
e s r a o C o t n o i t c a r F
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0
Reduced Efficiency Curve
0.1
1 D/D50c
10
Efficiency Curve Model - I
(e
d
E o( d 50 c ) = C • (e
α •
α
− 1)
d d 50 c
)+e
α
−2
Efficiency Curve - Varying 1 .0 0 .9 0.25
0 .8 e n i F o t n o i t c a r F
0 .5 1
0 .7
2 3
0 .6
5 7 .5
0 .5
10
0 .4 0 .3 0 .2 0 .1 0 .0 1
10
100
Size ( m )
1000
Reduced Efficiency – Constant for a Given Mineral
D50 Equation d 50 c D c
= K D 2
K D 2 = K D 1
D o
0 . 52
D c
D i
− 0 .5
D c
K D 1 = K D 0 D
− 0 . 65
Du
− 0 . 47 0 . 93
λ
D c L c D c
0 .2
θ
0 . 15
(
P
( ρ p gD c
)
− 0 . 22
Recovery to Underflow - I R f = K w 2
Do
−1.19
Dc
K w 2 = K w1
Di Dc
Du
2.40
Dc
− 0.50
θ
− 0.24
P
( ) ρ pgDc
Lc Dc
0.22
− 0.53
0.27
λ
Recovery to Underflow - II R v = K v 2
D o
− 0 . 94
D u
D c
K v 2 = K v 1
D i D c
1 . 83
D c
− 0 . 25
θ
− 0 . 24
(
P
ρ p gD c
L c D c
0 . 22
)
− 0 . 31
Pressure-Throughput Equation Q = K Q 2 D
c
K Q 2 = K Q 1 (
2
(
P
ρ p
Di D
K Q 1 = K Q 0 D
c
)
)
0 .5
0 . 45
c
− 0 .1
(
θ
D
o
D
c
− 0 .1
)
(
0 . 68
L c D
c
)
0 .2
Fish Hook Effect - I 1 e n i F o t n o i t c a r F
0.8 0.6 0.4 0.2 0 10
100 Size ( m )
1000
Fish Hook Effect - II
Exaggerated in graph Assumed originally to be caused by changing size measurement technique With advent of wide size range measurement techniques (Laser etc) - phenomenon really occurs sometimes Assumptions about short-circuiting of particles with water breaking down High viscosity and large cyclones???
Efficiency Curve Model - II
d
*
E
d o( ) d 50 c
(1 + β • β • = C• (e
d 50 c
d α • β * • d 50 c
α
)( e − 1) α
)+e −2
Efficiency Curve - Varying 1 .4 1 .2
0 .0 0 .2
e n i F o t n o i t c a r F
1 .0
0 .5 1 .0 2 .0
0 .8 0 .6 0 .4 0 .2 0 .0 0 .1 0
1 .0 0
1 0 .0 0 Size ( m )
1 0 0 .0 0
1 0 0 0 .0 0
Cyclone Parameters - I
JKSimMet
Geometry Data
Cyclone Parameters - II
JKSimMet
Model Parameters
Cyclone Parameters - III
JKSimMet
Performance Data
SG Effects - 1 1.0 0.9 e 0.8 n i F 0.7 o 0.6 t n 0.5 o i t 0.4 c a 0.3 r F 0.2 0.1 0.0
Galena Sphalerite Silica
10
100 d50c (Ga)
Size ( m )
1000 d50c (Sp)
d50c (Si)
SG Effects - 2 1.0 0.9 e 0.8 n i F 0.7 o 0.6 t n 0.5 o i t 0.4 c a 0.3 r F 0.2 0.1 0.0
Galena Sphalerite Silica Average
10
100 d50c (Ga)
Size ( m )
1000 d50c (Sp)
d50c (Si)
D50 Equation - II
K D0 depends on feed solids characteristics only size & sg
d 50 c ( m ) =
sg feed - 1 sg mineral - 1
∗ d 50 c
Fitting the Cyclone Model - I
Use measured pressure wherever possible If in doubt about measured pressure, compare with manufacturer’s tables Make sure the Measured Pressure is available to Model Fitting by activating it on the Equipment Data Tab of the Model Fit Dialog window Typical values of K Q0 are 300 - 600
Fitting the Cyclone Model - II
K D0 is typically 0.001 - 0.00001 Actual water split to O/F is fitted rather than K V1 and K W1 (both controlled by the water split) You can calculate an estimate of the water split from the mass balanced water flow data Always fit the Water Split
Fitting the Cyclone Model - III
If the fit is poor at fine sizes, try setting β to 0.1. If this improves the fit, then fit β. Plotting and inspecting the efficiency curve will help (Remember that you need data in the cyclone feed combiner port to plot efficiency curves)
Design Considerations - I
Cut Size – Cyclone Diameter • smaller > finer
– Operating Pressure • higher > finer
– Feed Density • lower > finer
– Inclination • flatter > coarser
Design Considerations - II
Water split to overflow – higher > more efficient <50%
very poor
50 - 60%
poor
60 - 70 %
reasonable
70 - 80%
typical of good operation
80 - 90%
subject to underflow limitations
>90%
not usually achievable
Design Considerations - III
Feed Size – coarse feeds limit water split to O/F – fine feeds increase viscosity – can’t create fine material in cyclone
Pressure – controls wear in pump and cyclone – trade-off between wear and operational flexibility
Design Considerations - IV
Operation at high overflow density – capital v operating trade off • capital – thickeners are expensive
Feed size effect – As the feed becomes coarser, d50c tends to decrease even when all the other variables are kept constant.
Efficiency curve equation – The analytic form used does not provide a perfect representation for the reduced efficiency curve.
Alternative Efficiency Curve Model 180 160 ) d 140 e t c e r 120 r o c ( w 100 o l f r e 80 v O o t 60 d e e F 40 f o %
Efficy. curve at 0.33xd50c
Efficy. curve at 0.66xd50c
Efficy. curve at d50c
20 0 0.00
0.50
1.00
1.50
d/d50(corrected)
2.00
2.50
Cyclone Model Limitations II
Viscosity – Viscosity variations due to changes in pulp density are largely accounted for by the model. – Viscosity variations caused by variable quantities of slimes affect the parameters in quite a systematic way.
Cyclone Model Limitations III
Increasing viscosity causes – coarser cut size – water split to overflow reduced – pressure drop increased – reduced efficiency curve constant till roping
Cyclone Model Limitations IV
Effect of roping – cut size increased by 5 to 10 – alpha value reduced to 0.1 - 0.2 – water split not affected much – pressure drop not affected much – inclination allows operation at higher underflow density before roping
Cyclone Model Limitations V
Prediction of roping difficult – SPOC constraint • feed density
– Plitt constraint • underflow size distribution
JKSimMet warns when either constraint is violated
Cyclone Model Limitations VI
SPOC Constraint at sg 2.7 Feed Underflow Feed Underflow Density Density Density Density % by Volume % by Weight 5 53 12.4 75.3 10 54 23.1 76.0 15 55 32.3 76.7 20 56 40.3 77.5 25 57 47.4 78.2 30 58 53.6 78.8 35 59 59.2 79.5
at sg 4.0 Feed Underflow Density Density % by Weight 17.4 81.8 30.8 82.4 41.4 83.0 50.0 83.6 57.1 84.1 63.1 84.7 68.3 85.2
Cyclone Model Limitations VI
SPOC Constraint at sg 2.7 Feed Underflow Feed Underflow Density Density Density Density % by Volume % by Weight 5 53 12.4 75.3 10 54 23.1 76.0 15 55 32.3 76.7 20 56 40.3 77.5 25 57 47.4 78.2 30 58 53.6 78.8 35 59 59.2 79.5
at sg 4.0 Feed Underflow Density Density % by Weight 17.4 81.8 30.8 82.4 41.4 83.0 50.0 83.6 57.1 84.1 63.1 84.7 68.3 85.2
Cyclone Model Limitations VI
SPOC Constraint at sg 2.7 Feed Underflow Feed Underflow Density Density Density Density % by Volume % by Weight 5 53 12.4 75.3 10 54 23.1 76.0 15 55 32.3 76.7 20 56 40.3 77.5 25 57 47.4 78.2 30 58 53.6 78.8 35 59 59.2 79.5
at sg 4.0 Feed Underflow Density Density % by Weight 17.4 81.8 30.8 82.4 41.4 83.0 50.0 83.6 57.1 84.1 63.1 84.7 68.3 85.2