distillation column design ( 2 ) packed column ( 2 ) heat exchanger design ( 2 cooler )

• 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


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


TypePacked

LocationAfter mix. 100


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


TypeShell and tube heat exchanger

LocationAfter Reactor (CRV-100)

UtilitySea Water


Cost ($)$344500

Operating Condition

Shell Side

Inlet temperature (oC)90Outlet temperature (oC)40

Tube Side


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


Cost ($)$ 4900

Operating Condition

Shell Side

Inlet temperature (oC)139.6Outlet temperature (oC)90

Tube Side


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

distillation column design ( 2 ) packed column ( 2 ) heat exchanger design ( 2 cooler )

Documents