mist extractor calculation

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7.3.4 Phase Separator
The parameters and composition of separator to calculate the detail calculation is being
refers from figure in fundamental above.
1. Density
The density was calculated based on the Appendix B which were done by interpolate
the data. The calculated density for all four components as follows with the parameters of 48.85o
C
and 36.38 atm.
Table 7.17: Density at 48.85o
C and 36.38 atm
Hydrogen, H2
(gas)
Methane, CH4
(gas)
Benzene, C6H6
(liquid)
Cyclohexane, C6H12
(liquid)
2.7701 22.4991 851.3196 755.4502
Interpolation (unit; ρ =
𝑘𝑔
𝑚3
⁄ )
2. Volume
Using the following formula:
𝜌 =
𝑚
𝑉
→ 𝑉̇ =
𝑚
̇
𝜌
a) Hydrogen, H2:
𝑉̇ =
7.489
𝑘𝑔
ℎ𝑟
⁄
2.7701
𝑘𝑔
𝑚3
⁄
= 2.7035 𝑚3
ℎ𝑟
⁄
b) Methane, CH4:
𝑉̇ =
35.565
𝑘𝑔
ℎ𝑟
⁄
22.4991
𝑘𝑔
𝑚3
⁄
= 1.5807 𝑚3
ℎ𝑟
⁄

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c) Benzene, C6H6:
𝑉̇ =
18.718
𝑘𝑔
ℎ𝑟
⁄
851.3196
𝑘𝑔
𝑚3
⁄
= 0.022 𝑚3
ℎ𝑟
⁄
d) Cyclohexane, C6H12:
𝑉̇ =
18656.716
𝑘𝑔
ℎ𝑟
⁄
755.4502
𝑘𝑔
𝑚3
⁄
= 24.6962 𝑚3
ℎ𝑟
⁄
Gas Volume: 𝑉̇𝑔𝑎𝑠 = 𝑉̇𝐻2 + 𝑉̇𝐶𝐻4 = 4.2842 𝑚3
ℎ𝑟
⁄
Liquid Volume: 𝑉̇𝑙𝑖𝑞𝑢𝑖𝑑 = 𝑉̇𝐶6𝐻6 + 𝑉̇𝐶6𝐻12 = 24.7182 𝑚3
ℎ𝑟
⁄
Total Volume: 𝑉̇𝑡𝑜𝑡𝑎𝑙 = 𝑉̇𝑔𝑎𝑠 + 𝑉̇𝑙𝑖𝑞𝑢𝑖𝑑 = 29.0024 𝑚3
ℎ𝑟
⁄
3. Vessel Sizing
Figure 7.25: Horizontal vapor – liquid separator
Based on Figure 7.26 below, it shows the ratio of length, L and diameter, D based on
the operating pressure of the vessel. Due to the pressure operated on the vessel are higher than
35 bar, thus the ratio suitable to be taken is the ration of 1:5.
L
H
D
Rc

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Figure 7.26: Table of length and diameter ratio
When, L = 10 m:
𝐿 = 5𝐷
𝐷 =
𝐿
5
𝐷 = 2 𝑚
Crown radius, Rc:
𝑅𝑐 =
𝐷
2
= 1 𝑚
a) Total Volume of Hemispherical Head
𝑉 =
2
3
𝜋𝑅𝑐3
=
2
3
𝜋(1𝑚)3
= 2.0944 𝑚3
× 2 ℎ𝑒𝑎𝑑𝑠
= 4.1888 𝑚3
b) Volume of Vessel Tank
𝑉 = 𝜋𝑟2
[(
4
3
) (𝑟) + 𝐿]
= 𝜋(1𝑚)2
[(
4
3
)(1𝑚) + 10𝑚]
= 35.6047𝑚3

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c) Level of Liquid Height, H
Interpolation based on the following table below:
Level (mm) Volume (m3
)
1400 26.77
1600 30.70
H 29.0024
Table 7.18: Liquid level in the vessel (CHECALC, 2015)
From the calculation above, the total volume of liquid in the vessel is 29.0024 m3
.
𝐻 − 1400
1600 − 1400
=
29.0024 − 26.77
30.70 − 26.77
𝐻 − 1400
200
= 0.5581
𝐻 = 1513.6081 𝑚𝑚
= 1.5136 𝑚
d) Mist Extractor
K factor has the specific value based on the operating pressure of separator. For the
pressure operated at 36.38 atm equivalent to 36.863 bar, the K factor was obtained by
interpolating the data from table below.
Pressure (bar) K (𝑚
𝑠
⁄ )
21.0 0.101
42.0 0.092
36.862 K
Table 7.19: K factor value based on operating pressure (Bahadori, 2014)
36.862 − 21.0
42.0 − 21.0
=
𝐾 − 0.101
0.092 − 0.101
𝐾 − 0.101
−0.009
= 0.7553
𝐾 = 0.0942 𝑚
𝑠
⁄

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e) Settling Velocity, Vt
𝑉𝑡 = 𝐾√
𝜌𝑙 − 𝜌𝑔
𝜌𝑔
= 0.0942 𝑚
𝑠
⁄ × √
(851.3196 − 22.4991)
𝑘𝑔
𝑚3
⁄
22.4991
𝑘𝑔
𝑚3
⁄
= 0.5717 𝑚
𝑠
⁄ 𝑜𝑟 2057.4 𝑚
ℎ𝑟
⁄
f) Gas Flow, QA
𝑄𝐴 =
𝑚
̇
𝜌𝑔
=
18718.487
𝑘𝑔
ℎ𝑟
⁄
22.4991
𝑘𝑔
𝑚3
⁄
= 831.966 𝑚3
ℎ𝑟
⁄
g) Area of Mist Extractor
𝐴 =
𝑄𝐴
𝑉𝑡
=
831.966 𝑚3
ℎ𝑟
⁄
2057.4 𝑚
ℎ𝑟
⁄
= 0.4044 𝑚2
Hence the area of the mist extractor in round shape, formula of circle is used to calculate the
diameter of mist extractor.

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h) Area of Circle
𝐴 = 𝜋𝑟2
0.4044 𝑚2
= 𝜋𝑟2
𝑟2
= 0.1287 𝑚2
𝑟 = 0.3587 𝑚
i) Diameter of Mist Extractor
𝐷 = 2𝑟
= 2(0.3587 𝑚)
= 0.7174 𝑚

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7.4.4 Phase Separator (Major)
The dimensions and measurements for the phase separator has been calculated earlier.
Figures below are showcasing the prototype of how the desired phase separator should look like.
The mechanical drawing for phase separator for both isometric and geometry was done by using
software “Autodest Inventor”.
a) Isometric Drawing
Figure 7.38: Equipment in Isometric Drawing
Inlet Diverter
Mist Extractor

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b) Geometry Drawing
Figure 7.39: Equipment in Geometry Drawing with scale and dimension

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7.5.4 Phase Separator (Major)
EQUIPMENT SPECIFICATION SHEET
General Information
Type of equipment Vapor – Liquid Separator, S–101
Function To separate mixture of vapor and liquid
Number of unit 1
Material of construction Stainless steel
Operating Information
Operating Pressure 36.38 atm
Operating Temperature 48.85°C
Operating Condition Continuous
Power Input 6785.29 W
Feed flowrate 18718.487 kg/hr
Molar flowrate 221.682 kmol/hr
Design Information
Vessel:
Type of vessel Horizontal vessel
Vessel head Hemispherical head
Vessel volume (m3
) 35.6047 m3
Diameter of vessel (m) 2.0 m
Head crown radius (m) 1.0 m
Length of vessel (m) 10.0 m
Length of vessel with head (m) 14.0 m
Inner part Inlet diverter, Mist extractor
Inlet Diverter:
Type of inlet diverter Stainless steel
Mist Extractor:
Type of mist extractor 8PP - Plastic mesh
Settling velocity 0.5717 m/s
Area of mist extractor (m2
) 0.4044 m2
Diameter of mist extractor (m) 0.7174 m
Diameter droplet 200.0 microns