supervised by: prof. mohamed fahim eng. yusuf ismail
DESCRIPTION
Kuwait University College of Engineering & Petroleum Depatment of Chemical Engineering. Propylene Oxide Production by Chlorohydrins Process (Cell- Liqure ). Done by Abdulrahman Habib. Supervised by: Prof. Mohamed Fahim Eng. Yusuf Ismail. Agenda. Distillation column design ( 2 ) - PowerPoint PPT PresentationTRANSCRIPT
• Distillation column design ( 2 )
• Packed column ( 2 )
• Heat exchanger design ( 2 Cooler )
Distillation Column Design
Objective
To separate PO desired product from by-products (PDC DCIPE).
Assumptions•Tray spacing= 0.6 m•Percent of flooding at maximum flow rate=85%•Percent of downcomer area of total area=12%•The hole area =10% the active area.•weir height=50 mm•Hole diameter=5 mm•Plate thickness=5 mm
Main Design Procedures
• Specify the properties of outlets streams for both vapor and liquid from HYSYS.
• Column Diameter
WhereFLv: liquid-vapor flow factorLw: liquid flow rate, kmol/hrρL: liquid density,kg/m3Vw: vapor flow rate, kmol/hrρv :vapor density, kg/m3
5.0)(*l
v
VW
LWFLV
• Get k1 for both bottom and top from figure 11.27 then use correction factor
K = (σ / 0.02) ^0.2 * K1
Where:
σ = liquid surface tension in N/m
• calculate the flooding velocity for top and bottom
Uf = K *( (ρl –ρV) / ρ v)½
Where:
Uf = flooding vapour velocity in m/sK= Surface tention correction factor
ρl = density of liquid in kg / m³ρv = density of vapour in kg / m³
• Assume the flooding percentage is 85% at max flow rate for the top and the bottom
UV = 0.85 * Uf
• calculate the net area for the top and the bottom
An = V / UV
Where:
An = net area in m²V = Volumetric flow rate in m³ / sUV = vapour velocity in m/s
• Assume as first trail take down comer as 12% of total cross sectional area
Ac = An /(1- 0.12)
Where:
Ac = cross sectional area in m²
• Calculate the diameter for the top and the bottom
D = ((4 /π) * Ac) ½
• Calculate the column height using the actual number of stage
H= (Tray spacing * actual NO. stage ) + D
Aa = Ac – 2Ad
Ah = 0.1 * Aa
Where:
Aa = active area in m²
Ah = hole area in m²
3600*)( Wt
WW
MLLMax
)3
2(
)*
)((*750)(
wierlengthL
LMaxhowMax W
)
3
2(
)*
)((*750)(
wierlengthL
LMinhowMin W
Check Weeping
3600*%)()( Wt
WW
MLturndownLMin
Where:max Lw: maximum liquid rate, (kg/s).min Lw : minimum liquid rate, (kg/s).max how: mm liquid.min how : mm liquid.
• Calculate the actual vapor velocity
Calculate the actual vapour velocity = min vapour rate / Ah
Uh(min)=[K2-0.90(25.4-dh)]/g0.5
Calculate Pressure Drop:
HD = 51 * (Uh/ C0)² * ρ V / ρL
Hr = 12.5E3 / ρL
Ht = HD + HW + HOW + HR
Where:Hd = dry plate dropUh = min vapour velocity in m/s Hr = residual headHt = total pressure drop in mm
Downcomer backup
hdchthowhwhb
Aapl
lowrateMaxliquidfhdc
hapwierlengthAap
mmhwHap
)(
)*
(*166
*
)(10
2
• Calculate the residence time
TR = (Ad * hb * ρ l) / lwd
• Calculate the flooding percentage
Flooding percentage = UV / uf * 100
• Calculate the area of the hole
A = (3.14 / 4 ) * (dh * 0.001 )²
• Calculate number of hole
Number of hole = A h / A
Pr
0.6i
oj
t CSE P
• Calculate the thickness
Where:
t: thickness of the separator in (in)P: operating pressure in Pisari: radius of the separator in (in)S: is the stress value of carbon steel = 13700 PisaEj: joint efficiency (Ej=0.85 for spot examined welding)C0: corrosion allowance = 0.125
Equipment NameDistillation Column
ObjectiveTo separate by-product (DCIPE & PDC) from
propylene oxide
Equipment NumberT-100
DesignerAbdulrahman Habib
Type Continuous Distillation Column
LocationAfter separator (V-101)
Material of ConstructionCarbon Steel
Cost ($)$ 400,810
Result
Column Flow Rates
Feed (kgmole/hr)893Recycle (kgmole/hr)23.1
Distillate (kgmole/hr)460.7Bottoms (kgmole/hr)455.3
Dimensions
Diameter (m)Two sizes
2.91 and 3.11Height (m)16.3
Number of Trays22Reflux Ratio4
Tray Spacing0.6Type of traySieve trays
Number of Holes29541
Cost
Vessel$ 88,300Trays$59,510
Condenser Unit$196,200Reboiler$56,800
Equipment NameDistillation Column
ObjectiveTo increase purity of
Equipment NumberT-101
DesignerAbdulrahman Al-Damaj
Type Continuous Distillation Column
LocationAfter Distillation (T-100)
Material of ConstructionCarbon Steel
Cost ($)$1,083,616
Column Flow Rates
Feed (kgmole/hr)460.7Recycle (kgmole/hr)-
Distillate (kgmole/hr)437.6Bottoms (kgmole/hr)23.1
Dimensions
Diameter (m)Two sizes
3.141 and 3.256Height (m)16.5
Number of Trays22Reflux Ratio4
Tray Spacing0.6Type of traySieve trays
Number of Holes32232
Cost
Vessel$87,100Trays$61,816
Condenser Unit$184,000Reboiler$750700
Objective
To produce PCH from react C3H6 + Cl2 + H2O PCH + HCl
Assumptions•" 3/4 in " Berl Saddles•Ej = 0.85•Cc = 0.125 in•Percent of flooding at maximum flow rate=90%
• Determine VVGG
Calculate
(∆P = 2 ;Fp= 175 since ¾ Bearl Saddle)
Then new capacity parameter is known (from figure 10.6-5)
First: Calculate Diameter (D)
• Determine the mass ratio
• Determine GG at 90% Flooding: GG = 0.9 * VG * ρG (Ib/s.ft2)
• Diameter (D):
Area = Feed Gas x (1/Gg)
Diameter = ( Area * π/4 )0.5 ft
Second: Calculate Height (HETP)
• Determine Gx & Gy
Gy = FG / Area (Ib/hr.ft2)
Gx = FL / Area (Ib/hr.ft2)
• Determine the HG & HL
HL =
HG=
• Determine NOG
NOGOG =
) Y-Y(*mm =
• Calculate the KYAYA
Kya =
Kxa =
1/KYAYA =
• Determine the Height (HETP)
Method # 1 Method # 2
HOG =HOG =
Height = HOG x NOG
• Calculate Thickness (T):
Pr
0.6i
oj
t CSE P
Where:
t: thickness of the separator in (in)P: operating pressure in Pisari: radius of the separator in (in)S: is the stress value of carbon steel = 13700 PisaEj: joint efficiency (Ej=0.85 for spot examined welding)C0: corrosion allowance = 0.125
Result
Equipment NamePacked Column
ObjectiveTo produce PCH from react C3H6 + Cl2 + H2O
Equipment NumberCRV-100
DesignerAbdulrahman Al-Damaj
TypePacked
LocationFirst Part of the Plant
Material of ConstructionCarbon steel
Cost ($)21,805.1
Operating Condition
Temperature (oC)40Diameter (ft)5.94
Pressure (psia)60 Height (ft)25.28
Type of packing
“ ¾ ” Berl
Saddles
Thickness (in)0.309
Equipment NamePacked Column
ObjectiveTo strip the H2O
Equipment NumberX-100
DesignerAbdulrahman Al-Damaj
TypePacked
LocationAfter mix. 100
Material of ConstructionCarbon steel
Cost ($)6,591.716
Operating Condition
Temperature (oC)90Diameter (ft)2.54
Pressure (psia)15 Height (ft)21.23
Type of packing
“ ¾ ” Berl
Saddles
Thickness (in)0.149
Heat Exchanger Design
To decrease the temperature of the stream leaving the reactor and prepare it before interring the next reactor.
Objective of ( E-100 )
Assumptions
• Using two shell pass and four or multiple of four tube passes.
• Assume the outer, the inner diameter and the length of the tube.
• The value of the overall heat transfer coefficient was assumed to be For = 750 w/m2C.
Main design procedures
1
2
12
T
TLN
TTTLM
ΔT1= Thi-Tco
ΔT2= Tho-Tci
Where, Thi: inlet hot stream temperature (˚C)
Tho: outlet stream temperature (˚C) Tci: inlet cold stream temperature (˚C)
Tco: outlet cold temperature
• Heat load ,(kW)
Q = (m Cp ΔT)hot =(m Cp ΔT)cold
• Log mean Temperature, (˚C)
• Provisional Area, (m2)
Where:
ΔTm= Ft ΔTlm
mo TU
QA
• Area of one tube = Lt * do *
Where:
Outer diameter (do), (mm)
Length of tube (Lt), (mm)
• Number of tubes
Nt= provisional area / area of one tube
• Bundle diameter
Db = do( Nt / K1) (1/n1) ,mm
Where:
Db: bundle diameter ,mm
Nt : number of tubes
K1 , n1 : constants from table (12.4) using triangular pitch of 1.25
• Shell diameter
Ds = Db + (Db Clearance) ,mm
Where :
we get it from figure (12.10) using split ring floating heat type.
• Tube side Coefficient
)hi di / κ = (jh Re Pr0.33 * (µ/µwall)0.14
• Shell side Coefficient
hs = κ * jh *Re *Pr (1/3) / de
• Overall heat transfer coefficient
1/Uo =1/ho + 1/hod + do(ln(do/di))/2kw + do/di * 1/hid + do/di * 1/hi
Where :
Uo : overall coefficient based on outside area of the tube ,w/m^2.C ho : outside fluid film coefficient, w/m^2.C
hi : inside fluid film coefficient ,w/m^2
hod : outside dirt coefficient (fouling factor) ,w/m^2.C, from Table (12.2)
hid : inside dirt coefficient (fouling factor),w/m^2.C from Table (12.2)
kw : thermal conductivity of the wall material w/m.Cs for cupronickel
di : tube inside diameter m
do : tube outside diameter m
• Pressure drop
Tube side:
ΔP = Np [ 8jf (L/di)(µ/µw)^(-m) +2.5 ] ρυ^2/2,kpa
Where:
ΔP : tube side pressure drop, N/m^2(pa)
Np : number of tube side passes
υ : tube side velocity ,m/s
L : length of one tube , m
jf : tube side friction factor
Shell side:
ΔPs = 8jf (Ds/de)(L/lb)( ρυ^2/2)(µ/µw)^(-0.14),kpa
Where:
L : tube length ,m
lb : baffle spacing ,m
• Shell thickness:
t = (P r i / S E - 0.6P) + Cc
Where :
t : shell thickness, in
P : internal pressure, psi gage
r i : internal radius of shell, in
E : efficiency of joints
S : working stress, psi (for carbon steel)
Cc : allowance for corrosion, in
Results Equipment NameCooler
ObjectiveTo cooled the feed stream and prepare it to inter
the reactor
Equipment NumberE-100
DesignerAbdulrahman Al-Damaj
TypeShell and tube heat exchanger
LocationAfter Reactor (CRV-100)
UtilitySea Water
Material of ConstructionCarbon steel
Cost ($)$344500
Operating Condition
Shell Side
Inlet temperature (oC)90Outlet temperature (oC)40
Tube Side
Inlet temperature (oC)25Outlet temperature (oC)45
Number of Tube Rows1481Number of Tubes5922
Tube bundle Diameter (m)2.88Shell Diameter (m)2.96
Q total (Kw)43439.42LMTD (oC)27.3
U (W/m2 oC)754.4Heat Exchanger Area (m2)2232.6
Equipment NameCooler
ObjectiveTo cooled the feed stream and prepare it to
inter the splitter
Equipment NumberE-108
DesignerAbdulrahman Habib
TypeShell and tube heat exchanger
LocationAfter Distillation (T-104)
UtilitySea Water
Material of ConstructionCarbon steel
Cost ($)$ 4900
Operating Condition
Shell Side
Inlet temperature (oC)139.6Outlet temperature (oC)90
Tube Side
Inlet temperature (oC)25Outlet temperature (oC)45
Number of Tube Rows2Number of Tubes6
Tube bundle Diameter (m)0.094Shell Diameter (m)0.14
Q total (Kw)44.52LMTD (oC)78.87
U (W/m2 oC)750Heat Exchanger Area (m2)0.767