KUWAIT UNIVERSITYCOLLEGE OF ENGINEERING &
PETROLEUMCHEMICAL ENGINEERING DEPARTMENT
Equipment design
Ethylbenzene production by liquid phase
Done by: Mohammed Almohsen
Supervised By:
Prof. M. A. Fahim
Eng. Yusuf Ismail
Distillation column:
Distillation T-101
Separate and recycle
Ethylbenzene
COLUMN DIAMETER:
LIQUID VAPOR FLOW FACTOR
FOR BOTTOMS
FOR TOP
TAKE PLATE SPACING AS 0.6 M
FROM FIGURE
BASE K1 = 0.08TOP K1 = 0.12
CORRECTION FOR
SURFACE TENSIONS
BASE K1 = 0.066TOP K1 = 0.1078
FLOODING VELOCITY:
DESIGN FOR 85% FLOODING AT MAXIMUM FLOW RATE
BASE
TOP
MAXIMUM VOLUMETRIC FLOW RATE
BOTTOM
TOP
NET AREA REQUIRED:
TAKING DOWNCOMER AREA AS 12 per cent OF TOTAL AREA
COLUMN CROSS-SECTIONAL AREA
COLUMN DIAMETER:
USE SAME DIAMETER ABOVE AND BELOW FEED =6.328M=20.76FT
COLUMN HEIGHT:
Column height = (Number of stage * Plate spacing) + Column Diameter
H = 27.9m =91.6 FT
LIQUID FLOW PATTERN:
MAXIMUM VOLUMETRIC LIQUID RATE
FROM FIGURE
DOUBLE PASS PLATE IS USED
PROVISIONAL PLATE DESIGN:
•Column diameter =
•Column area =
•Downcomer area =
•Net area =
•Active area =
•Hole area =
FROM FIGURE
WEIR LENGTH
•Take weir height =
•Hole diameter =
•Plate thickness =
ASSUME
CHECK WEEPING:
MAXIMUM LIQUID RATE
TURNDOWN PERCENTAGE = 0.80
MINIMUM LIQUID RATE
MAXIMUM WEIR CREST:
MINIMUM WEIR CREST:
AT MINIMUM RATE
FROM FIGURE
MINIMUM VAPOR VELOCITY THROUGH HOLE:
ACTUAL MINIMUM VAPOR VELOCITY
SO MINIMUM OPERATING RATE WILL BE ABOVE WEEP POINT.
PLATE PRESSURE DROP:
MAXIMUM VAPOR VELOCITY THROUGH
HOLES
Plate thickness / hole dia. = 1.25
FROM FIGURE
DRY PLATE DROP
RESIDUAL DROP
TOTAL PLATE PRESSURE
DROP
DOWN COMER LIQUID BACK-UP:
DOWNCOMER PRESSURE
LOSS
TAKE
AREA UNDER APRON
HEAD LOSS IN THE DOWNCOMER
BACK-UP IN DOWNCOMER
CHECK RESIDENCE
TIME
SATISFACTORY
CHECK ENTRAINMENT
FROM FIGURE
ψ =0.013 , well below 0.1
PERFORATED AREA:
FROM FIGURE
•Angle subtended by the edge of the plate = 85
•Mean length, unperforated edge strips =
9.3136
•Area of unperforated edge strips= 0.4191 m
•Mean length of calming zone,approx =4.7738
•Area of calming zones =0.4296 m
•Total area for perforations, Ap =23.0532
FROM FIGURE
NUMBER OF HOLES:
AREA OF ONE HOLE:
NUMBER OF HOLES:
AREA OF CONDENSER
Inlet temperature T1
159.8721
Co
Outlet temperature T2
158.5811
Co
Mean overall heat transfer coefficient
U
1000.0000
W/m2.Co
Heat flow Q
52720.0000
KW
Inlet temperature T1
231.8769
Co
Outlet temperature T2
230.4711
Co
Mean overall heat transfer coefficient
U
1000.0000
W/m2.Co
Heat flow Q
50810.0000
KW
AREA OF REBOILER
THICKNESS CALCULATIONS:
Internal raduis of shell before allowance corrosion
is added ri
124.567
in
Maximum allowable internal pressure P
100.000
psi
Working stress for carbon steel S
13706.660
psi
Efficincy of joients EJ
0.850
Allowance for corrosin Cc
0.125
in
SPECIFICATION SHEET OF BENZENE
COLUMNEquipment
T-101 Name
Benzene Column
Objective
Separate and recycle Benzene to the reactor
Equipment Number
T-101
Designer
Mohammed Al-Mohsen
Type
Continuous Distillation Column
Location
After Mixer (MIX-108)
Material of Construction
Carbon steel
Insulation
Mineral wool
Cost ($)
$711,828
Operating Condition
Operating Temperature (oC)
171
Operating Pressure (psi)
100
Feed Flow Rate (kg/h)
451181
Diameter (m)
6.328
Height (m)
27.9
COST CALCULATIONS:
•
Column cost:
•
Cost of tray =
•
Cost of trays = 52,800$
•
Cost of Vessel:
•
Diameter outside=6m
•
Volume outside=895
•
Volume inside=878
•
Volume of metal=17
•
Weight of metal=296,080lb
•
Cost of vessel 2007 =547,200$
•
Vessel type: Large ,No Internals , Medium
•
Cost of reboiler:
•
Cost 2007 = 39,300$
•
Cost of condenser:
•
Cost 2007 =19,800$
•
Total cost of without insulation=659,100$
•
Insulation cost = 52,728$
•
Total cost of T-101=711,828$
1,100
$/trays
FROM:
WWW.MATCHE.COM
Heat exchanger:
3 heat exchanger has been designE-102 ,E103 and e-105.
The type of the 3 heat exchanger are shell and tube.
Cooler E-102 detailed calculation:
•
Heat load:
•
BECAUSE THERE IS PHASE CHANGE
COOLING FLOW:
TRY AND ERROR
ASSUME
TEMPERATURE CORRECTION
FACTOR: CALCULATION:
USING ONE SHELL PASS AND TWO TUBE PASSES
FROM FIGURE
ASSUME
PROVISIONAL AREA:
CHOOSE TUBE MATERIAL TO BE carbon steel WITH THE
FOLLOWING PROPERTY
OUTER DIAMETER Do = 25 MMINNER DIAMETER Di = 20
MMTUBE LENGTH = 4.88 M
AREA OF ONE TUBE
NUMBER OF TUBES
Nt = provisinal area / area of one tube = 792.36 = 793
USING 1.25 TRIANGULAR PITCH
TUBE BUNDLE
DIAMETER:
CONSTANT
USING SPLIT RING FLOATING
HEAD TYPE
FROM FIGURE
Bundle diametrical clearance = 71 mm
Shell diameter =Bundle diameter+Bundle diametrical clearance
=1037.13 mm=1.037
TUBE-SIDE COEFFICIENT:
• Mean water temperature =
• Tube cross sectional area =
• Total flow area=Tubes per pass x Cross
sectional area=
METHOD 1
• Water mass velocity=mass flow rate/total flow area=
• Water linear velocity U = mass velocity / density =
t
• Inside coefficient for water h :
i
TUBE-SIDE COEFFICIENT:
•REYNALDO NUMBER
•PRANDTL NUMBER
FROM FIGURE
HEAT TRANSFER
FACTOR
METHOD 1I
•INSIDE COEFFICIENT FOR WATER
Hs:
SHELL-SIDE COEFFICIENT:
• Choose baffle spacing =
• Tube pitch =
• Cross flow area=
• Mass velocity Gs= mass flow rate/cross flow area
=
• Equivalent diameter for triangular arrangement
• Mean shell side diameter temperature:
• Reynaldo number
• Prandtl number
CHOOSE 25% BAFFLE CUT
HEAT TRANSFER
FACTOR
FROM FIGURE
OVERALL HEAT TRANSFER COEFFICIENT:
• Thermal conductivity of steel =
• Outside coefficient (fouling factor) =
• Inside coefficient (fouling factor) =
CLOSE TO INITIAL VALUE ASSUMED
PRESSURE DROP:
TUBE SIDE:
FROM FIGURE
HEAT TRANSFER
FACTOR
SHELL SIDE:
Linear velocity =
FROM FIGURE
SHELL THICKNESS CALCULATIONS:
Internal raduis of shell
before allowance
corrosion is added ri
20.416
in
Maximum allowable
internal pressure P
85
psi
Working stress for carbon
steel S
13706.66
psi
Efficincy of joients EJ
0.85
Allowance for corrosin Cc
0.125
in
•
Cost Calculations:
•From www.matche.com
•Heat transfer area = 3,269 ft2
•Exchanger Type: Carbon steel
•Internal Pressure: 450 psi
•Cost with out insulation: 110,900$
•Insulation cost: 8,872$
•Final cost 2007:119,772$
Equipment Name
Heat exchanger
Objective
Heat the Benzene recycled stream before feed to the distillation
Equipment Number
E-102
Designer
Mohammed Al-Mohsen
Type
Shell and Tube Heat Exchanger
Location
After E-103 Heat Exchanger
Utility
Cooling Water
Cupro Nickel for shell side
Carbon Steel for tube side
Material of Construction
Insulation
Glass wool
Cost ($)
$110,900
Operating Condition
Shell Side
Inlet temperature (C)
159.38
Outlet temperature (C)
158.58
Inlet temperature (C)
27
Outlet temperature (C)
78
Number of Tube Rows
2
Number of Tubes
793
Tube bundle Diameter (m)
0.966
Shell Diameter (m)
1.037
Q total (kW)
22617
LMTD (oC)
104.48
U (W/m2C)
738
Heat Exchanger Area (m2)
303.69
Tube Side
Equipment Name
Heat exchanger
Heat the polyethylbenzen recycled stream before feed to Transreactor
Objective
Equipment Number
E-105
Designer
Mohammed Al-Mohsen
Type
Shell and Tube Heat Exchanger
Location
After P-101 pump
Utility
Cooling Water
Cupro Nickel for shell side
Carbon Steel for tube side
Material of Construction
Insulation
Glass wool
Cost ($)
$110,880
Operating Condition
Shell Side
Inlet temperature (C)
247.8
Outlet temperature (C)
127.5
Inlet temperature (C)
27
Outlet temperature (C)
45
Number of Tube Rows
4
Number of Tubes
12
Tube bundle Diameter (m)
0.157
Shell Diameter (m)
0.205
Q total (kW)
256.5
LMTD (oC)
145.69
U (W/m2oC)
608.4
Heat Exchanger Area (m2)
2.736
Tube Side
Equipment Name
Heat exchanger
Objective
Heat the Benzene recycled stream using the hot product stream from the reactor
Equipment Number
E-103
Designer
Mohammed Al-Mohsen
Type
Shell and Tube Heat Exchanger
Location
Between Mix-106 and Flash drums V-100
Utility
Cooling Water
Cupro Nickel for shell side
Carbon Steel for tube side
Material of Construction
Insulation
Glass wool
Cost ($)
$354,996
Operating Condition
Shell Side
Inlet temperature (oC)
158.6
Outlet temperature (oC)
159.4
Inlet temperature (oC)
267.9
Outlet temperature (oC)
190
Number of Tube Rows
2
Number of Tubes
3026
Tube bundle Diameter (m)
1.844
Shell Diameter (m)
1.942
Q total (kW)
22294
LMTD (oC)
62.2
U (W/m2oC)
334.755
Heat Exchanger Area (m2)
12987
Tube Side