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REPORT TO DEPARTMENT OF CHEMICAL ENGINEERING EGE UNIVERSITY
FOR
COURSE: CHE386 CONCEPTUAL DESIGN II
CSTR DESIGN FOR ETHYL ACETATE PRODUCTION
DESIGN REPORT I
Prof. Dr. Ferhan ATALAY
SUBMITTED TO
08/03/10
SUBMISSION DATE
05070008901 Ürün ARDA
GROUP 3
05070008103 Berna KAYA 05070008849 Demet ACARGİL
05060008091 M. Serkan ACARSER 05060008017 Tayfun EVCİL
i
SUMMARY
This report is about the production ethyl acetate by the esterification reaction of acetic
acid and ethanol. Both components are in aqueous solution; the acetic acid is 96% pure and
ethanol is 96.5% pure. The reactants are fed to a CSTR at 750 C. The products are also
at 750
In the CSTR calculation which is the main part of the report, six-blade turbine is
chosen, and the motor power was calculated as 4.441 kW . A CSTR, most commonly, is
heated by either a jacket or an internal coil. In jacket calculations heat transfer area was found
as 6.36 m
C.
2, mass flow as 60.434 kg/s, Tout as 197.94 0C , hi as 574.043, ho as 921.845 and U0
as 347.32 W/m2K. In coil calculations heat transfer area was found as 3.14 m2, mass flow as
3.537 kg/s, Tout as 164.866 0C, hi as 2001.16 , ho as 903.283 and U0 as 818.318 W/m2
K.
Finally, the number of coils was calculated as 6. Necessary calculations for both jacket and
coil were performed and the necessary comparisons were made in discussion part.
ii
TABLE OF CONTENTS
Summary ....................................................................................................................... i
1.0 Introduction ........................................................................................................... 1
2.0 Results ..................................................................................................................... 3
3.0 Discussion ................................................................................................................ 8
4.0 Nomenclature ....................................................................................................... 11
5.0 References ............................................................................................................ 13
6.0 Appendix .............................................................................................................. 14
- 1 -
1.0 INTRODUCTION
Ethyl acetate (systematically, ethyl ethanoate, commonly abbreviated EtOAc or EA) is the organic compound with the formula CH3COOCH2CH3. This colorless liquid has a characteristic sweet smell (similar to pear drops) like certain glues or nail polish removers, in which it is used. Ethyl acetate is the ester of ethanol and
acetic acid; it is manufactured on a large scale for use as a solvent. In 1985, about 400,000 tons were produced yearly in Japan, North America, and Europe combined.In 2004, an estimated 1.3M tons were produced worldwide.
PRODUCTION
Ethyl acetate is synthesized industrially mainly via the classic Fischer esterification reaction of ethanol and acetic acid. This mixture converts to the ester in about 65% yield at room temperature: CH3CH2OH + CH3COOH ⇌ CH3COOCH2CH3 + H2
O
The reaction can be accelerated by acid catalysis and the equilibrium can be shifted to the right by removal of water. It is also prepared industrially using the Tishchenko reaction, by combining two equivalents of acetaldehyde in the presence of an alkoxide catalyst: 2 CH3CHO → CH3COOCH2CH
3
By dehydrogenation of ethanol
A specialized industrial route entails the catalytic dehydrogenation of ethanol. This method is less cost effective than the esterification but is applied with surplus ethanol in a chemical plant. Typically dehydrogenation is conducted with copper at an elevated temperature but below 250 °C. The copper may have its surface area increased by depositing it on zinc, promoting the growth of snowflake, fractal like structures (dendrites). Surface area can be again increased by deposition onto a zeolite, typically ZSM-5. Traces of rare earth and alkali metals are beneficial to the process. Byproducts of the dehydrogenation include diethyl ether, which is thought to primarily arise due to aluminum sites in the catalyst; acetaldehyde and its aldol products; higher esters; and ketones. Separations of the byproducts is complicated by the fact that ethanol forms an azeotrope with water, as does ethyl acetate with ethanol and water, and methyl ethyl ketone
(MEK, which forms from 2-butanol) with both ethanol and ethyl acetate. These azeotropes are "broken" by pressure swing distillation or membrane distillation.
USES
Ethyl acetate is primarily used as a solvent and diluent, being favored because of its low cost, low toxicity, and agreeable odor. For example, it is commonly used to clean circuit boards and in some nail varnish removers (acetone and acetonitrile are also used). Coffee beans and tea leaves are decaffeinated
with this solvent. It is also used in paints as an activator or hardener.Ethyl acetate is present in confectionery, perfumes, and fruits. In perfumes, it evaporates quickly, leaving but the scent of the perfume on the skin.
- 2 -
LABORATORY USES
In the laboratory, mixtures containing ethyl acetate are commonly used in column chromatography and extractions. Ethyl acetate is rarely selected as a reaction solvent because it is prone to hydrolysis and
transesterification.
In organic chemistry, especially in experiment, since ethyl acetate is very volatile and with low boiling point, it can be removed by compressed air in a hot water bath.
OCCURRENCE IN WINES
Ethyl acetate is the most common ester in wine, being the product of the most common volatile organic acid — acetic acid, and the ethyl alcohol generated during the fermentation. The aroma of ethyl acetate is most vivid in younger wines and contributes towards the general perception of "fruitiness" in the wine. Sensitivity varies, with most people having a perception threshold around 120 mg/L. Excessive amounts of ethyl acetate are considered a wine fault. Exposure to oxygen can exacerbate the fault due to the oxidation of ethanol to acetaldehyde, which leaves the wine with a sharp
vinegar-like taste.
OTHER USES
In the field of entomology, ethyl acetate is an effective asphyxiant for use in insect collecting and study. In a killing jar charged with ethyl acetate, the vapors will kill the collected (usually adult) insect quickly without destroying it. Because it is not hygroscopic, ethyl acetate also keeps the insect soft enough to allow proper mounting suitable for a collection.
- 3 -
2.0 RESULTS
Table 1. Assuming and reference data of coil, jacket and oil
Coil Jacket
Assuming Data Ref. Data Assuming Data Ref. Data
υcoil 3 [m/s] k [W/mK] 0.1105 υjacket 0.6 [m/s] Cpoil 2204 [J/kg.K]
Tin [o 200 C] Cp [J/kg.K] 2147.4983 Tin [o 200 C] ρoil 897.6 [kg/m3]
do 1.9 [in] μ [Pa.s] 0.86*10 t-3 shell 1.5 [cm] koil 0.109 [W/m.K]
di 1.61 [in] ρ [kg/m3 910.2406 ] tjacket 2.3 [cm] μoil 0.73*10[Pa.s] -3
Table 2. Agitator calculation
Agitator Calculation Results
Dtank [m] Htank [m] dag [m] E [m] Re Np [from fig.] P [kW] Pact [kW] Pmotor [kW]
1.5 1.95 0.5 4.5 1*10 7 6 1.537 3.074 4.441
- 4 -
Table 3. Properties of the components
Properties AcA EtOH EtAc H2O
Cp [50°C] [J/kgK] 2160 2670 2020 4180
Cp [75°C] [J/kgK] 2280 2960 2120 4190
ΔHf -486180 [J/mol] -277630 -463200 285840
Table 4. Density Correlations for Components (75°C)
Density Correlations for Components (75°C)
T MW C1 C2 C3 C4 ρ (kmol/m3) ρ (kg/m3)
AcA 348 60.0520 1.449 0.25892 591.95 0.2529 16.4726 989.2111
EtOH 348 46.0680 1.629 0.27469 514 0.23178 16.0271 738.3386
EtAc 348 88.1050 0.900 0.25856 523.3 0.278 9.4389 831.6123
Water 348 18.0150 -13.851 0.64038 -0.00191 1.8211E-06 54.4414 980.7616
- 5 -
Table 5. Viscosity Correlations for Components (75°C)
Viscosity Correlations for Components (75°C)
T C1 C2 C3 C4 C5 μ (Pa.s)
AcA 348 -9.0300 1212.300 -0.322 - - 5.93*10-4
EtOH 348 7.8750 781.980 -3.0418 - - 4.62*10-4
EtAc 348 14.3540 -154.600 -3.7887 - - 2.58*10-4
Water 348 -52.8430 3703.600 5.866 -5.88E-29 10 3.81*10-4
Table 6. Properties of the components after mixing, at 75°C
ρ,mix [kg/m3] μ,mix [Pa.s] k,mix [W/mK] Cp,mix (Pa.s)
878.489 0.000429 0.15 2898.1
Table 7. Flow rates of components
FAcA [kmol/min] FEtOH[kmol/min] FEtAc [kmol/min] FWater [kmol/min] FTOTAL[kmol/min]
0.636 0.745 0.453 0.54 2.374
- 6 -
Table 8. Concentrations of components at the exit
CAcA [kmol/m3] CEtOH[kmol/m3] CEtAc [kmol/m3] CWater [kmol/m3]
10.411 11.959 7.273 8.698
-rAcA = 0.152 kmol/m3min
Vliquid= 2.983 m3
Vtank= 3.43 m3
Table 9. Mole fraction of the components
XAcA XEtOH XEtAc XWater
0.27 0.31 0.19 0.23
Table 10. Weight fraction of the components
XAcA XEtOH XEtAc XWater
0.31 0.28 0.32 0.09
- 7 -
Table 11. Results from calculations
Coil Jacket
Results Results m [kg/s] 3.536 ΔHf 268321 [W] ΔT [0 35.134 C] ΔHR -240722 [W] Tout [0 164.886 C] ΔHP 246276 [W]
hi [W/m2 2001.1634 .K] Q=ΔHrxn 273875 [W] hic [W/m2 10266.838 .K] Dji 1.530 [m] ho [W/m2 903.282 .K] Dio 1.576 [m] Uo [W/m2 818.318 .K] Tout [0 197.944 C]
D’ [m] 1.1 G [kg/m2 538.834 s] Perimeter of one coil [m] 3.45 deq 0.0933 [m]
Areq [m2 3.0403 ] hi [W/m2 574.043 K] # of coil 6 ho [W/m2 921.845 K] Hcoil 1 [m] Uo [W/m2 347.32 K]
Areq [m2 6.36 ]
Ao,cal [m2 9.189 ]
- 8 -
3.0 DISCUSSION
A reversible reaction is a chemical reaction that results in an equilibrium mixture of reactants and products. For a reaction involving two reactants and two products this can be expressed symbolically as
A and B can react to form C and D or, in the reverse reaction, C and D can react to form A and B. This is distinct from reversible process in thermodynamics.
The concentrations of reactants and products in an equilibrium mixture are determined by the analytical concentrations of the reagents (A and B or C and D) and the equilibrium constant Kc Gibbs free energy
. The magnitude of the equilibrium constant depends on the change for the reaction. So, when the free energy change is large (more than about 30
kJ mol-1
To make this endothermic reaction irreversible, the water must be removed from the system at all times. However, in CSTR, which has a closed top, this is not possible. So the reaction’s conversion becomes a percentage of the equilibrium reaction, which changes between 80-90% in ideal cases. 80% of the equilibrium conversion was assumed for this report. The reaction’s conversion depends on many factors, such as temperature, the weight percentage of the catalyst in reaction (the catalyst in this reaction is H
), then the equilibrium constant is large (log K > 3) and the concentrations of the reactants at equilibrium are very small. Such a reaction is sometimes considered to be an irreversible reaction, although in reality small amounts of the reactants are still expected to be present in the reacting system. A truly irreversible chemical reaction is usually achieved when one of the products exits the reacting system, for example, as does carbon dioxide (volatile) in the reaction. In this case, the reversible reaction is between acetic acid and ethyl acetate, such that:
2SO4
, with a weight percentage of 1.91%), presence of inert in the system, purity of the components and whether the tank is perfectly mixed. In this report, the components were taken as aqueous solutions, with mole percentage of acetic acid being 96%, and that of ethanol’s percentage being 96.5%. These factors also affect the reactor tank’s volume, due to the CSTR design equation. With mole balance and CSTR design equation, the inlet and outlet molar rates were calculated, and the inlet water of the solutions was added to the effluent water.
- 9 -
Concentrations were calculated from the rate equation. The k values of the rate equation depend on temperature and the weight percentage of the catalyst in the system. Upon finding these k and concentration values the rate of acetic acid’s formation was calculated. After finding the rate, the reaction volume was calculated as 2.983 m3
The safety factor was added to the reaction volume and the tank volume was found as 3.43 m
.
3
To heat the coil, many options are available. One can heat the components at a separate heat exchanger before feeding to the reactor, a jacket can be used, or a certain number of coils can be installed in the reactor. Choosing the heating fluid is very important, because choosing saturated steam (hence using steam generator) might cause additional expenses. Saturated steam is used in bigger industries in order to take advantage of its heating, and to generate electricity by means of steam turbines. Hot oil is a cheaper fluid to obtain, and for this reason hot oil was used as heating fluid. The velocity of the hot oil affects the heating of the reactor, as the velocity affects the Reynold’s number, the Nusselt number, and the convection heat coefficient as a result. The pipes and pumps can be picked to obtain the desired mass flow rate. The Nusselt number of the jacket and coils were calculated using the Chilton-Drew-Jebend’s correlation. The wall thickness of the jacket and reactor affects heat transfer because the mass flow rate, the heat transfer area and the temperature difference change.
. After finding the volume, the diameter and the height of the tank was calculated as 1.5 and 1.95 m respectively. The diameter of the agitator was calculated as 0.5 m.
The jacket was calculated first, which can be seen in appendix. To calculate the heat requirement for this endothermic reaction, hypothetical steps formed such that the reactor’s temperature, which was 75°C, was virtually dropped down to 25°C; and the reaction take place in this temperature. The products and the remaining components are then heated up to 75°C. Since the temperature of the entering and exiting components were 75°C, the only remaining factor was ΔHrxn in energy balance equation. The formation enthalpies at 25°C were found from references. The velocity of hot oil was assumed as 0.6 m/s, and then the temperature difference was calculated between the entrance and the exit of the jacket as 2.05 0
After finding the velocity and mass flow rate, using the correlations, h
C. If a higher velocity had been assumed, the mass flow rate would increase, required heat transfer area decrease and the pressure drop would change, a pump and pipe with a bigger diameter would be needed and this would cause more expensive operations and the temperature difference will be affected.
o was calculated as 921.845 W/m2K. The viscosity, specific heat and thermal conductivity of hot oil were taken at 200°C. With these data, hi was calculated as 574.043 W/m2K. After that Uo was found as 347.32 W/m2K, and the area necessary for heating was calculated as 6.36 m2. The jacket satisfies the reactor.
- 10 -
The same steps were followed for the coil, only that the number of coils was additionally calculated as 6, with the coils being a certain distance such as 20 cm away from the tank wall. Using coil for this reactor is a better option, because coil has a smaller area which lessens the required amount of hot oil as 3.536 kg/s , therefore making the reaction costly efficient.
In the agitation systems, we chose open turbine agitator with six-bladed impeller with four baffles. We chose our propeller speed as 2 rps, and the motor power needed was calculated as 4.441 kW. The safety factor and efficiency were also added for finding the actual power.
- 11 -
4.0 NOMENCLATURE
Fi : Molar flowrate of ith
X: Conversion
component [kmol/min]
T : Temperature [o
C
C]
i: Concentration of ith component [kmol/m3
D
]
T
H
: Tank diameter [m]
T
N: Rotational speed [rps]
: Height of tank [m]
NP
E: Distance between reactor bottom and impeller [m]
: Power number
D’
P
: Diameter of one coil [m]
o
Q : Heat taken/given from the reactor [W]
: Operating power [W]
U0: Overall heat transfer coefficient [W/m2
D
.K]
ji
D
: Inner diameter of jacket [m]
jo
G: Mass flux [kg/m
: Outer diameter of jacket [m] 2
Re: Reynolds number
.s]
Vtank : Volume of tank [m3
V
]
liq : Volume of reaction mixture [m3
d
]
ag
-r
: Agitator diameter [m]
A : Rate of reaction with respect to component A [kmol/m3
k : Specific reaction rate
min]
im : Mass flowrate of ith
d
component [kg/h]
o
d
: Outer diameter of coil [m]
i
h
: Inner diameter of coil [m]
i: Convective heat transfer coefficient inner fluid [W/m2
h
.K]
o: Convective heat transfer coefficient outer fluid [W/m2
.K]
- 12 -
Greeks
ρ : Density [kg/m3
µ
]
: Viscosity [Pa.s]
iυ : Volumetric flowrate of ith component [m3
η : Efficiency
/min]
ΔH: Enthalpy of out/ in/ reaction [W]
Subscripts
i: ith
i: Inner
component
o: Outer
ag: Agitator
- 13 -
5.0 REFERENCES
1. Richard M.Felder, Ronald W.Rousseau, 2000, Elementary Principles of Chemical
Processes, 3rd
Ed., John Wiley & Sons, Inc., USA.
2. Sümer Peker, Şerife Ş.Helvacı, 2003, Akışkanlar Mekaniği – Kavramlar, Problemler, Uygulamalar, 1st
Ed., Literatür Yayıncılık, İstanbul.
3. Perry’s R. H., Chilton, 2008, Chemical Engineers’ Handbook, 8th
Edition, Mc Graw-
Hill Kokagusha, Tokyo.
4. Warren L. McCabe, Julian C.Smith, Peter Harriot, 1993, Unit Operations of Chemical
Engineering, 5th
Ed., McGraw-Hill, Singapore
5. Incropera, P.F., DeWitt, D.P., 2007, Fundamentals of Heat and Mass Transfer, 6th
Ed., John Wiley & Sons, Inc., Canada.
6. J.M.Smith, H.C.Van Ness, M.M.Abbott, 2005, Introduction to Chemical Engineering Thermodynamics, 7th
Ed., McGraw-Hill, Singapore
7. Octave Levenspiel, 1999, Chemical Reaction Engineering, 3rd
Ed., John Wiley & Sons, Inc.,USA.
8. Atalay, F.S., 1994, "Kinetics of the Esterification Reaction Between Ethanol and Acetic Acid", Developments in Chemical Engineering and Mineral Processing, Vol.2, p.181-184.
9. http://www.processglobe.com/Liquid_Specific_Heat.aspx
- 14 -
6.0 APPENDIX
Calculation of the Volume of the CSTR
Name Composition Initial Change Remaining Acetic Acid A
0AF
0*
AF x− ( )
01A A
F F x= −
Ethanol B 0B
F 0
*A
F x− ( )0
B BAF F xθ= −
Ethyl Acetate C — 0
*A
F x+ 0
*C AF F x=
Water D 0D
F 0
*A
F x+ ( )0
D DAF F xθ= −
0 0 0
0 0,
1 1 1 100021000 * * * *365 24 60 1
39.954 , 39.954 * 0.45388.1
*0.8 , 0.52 ; 0.52*0.8 0.416
* ; 0.453 *0.416 , 1.09
*0.96 ; 1.feed
C
C C
e e
C A A A
A A
year day h kgtonFyear day h min ton
kg kmolF kg min F kmol minmin kg
x x x xF F x F F kmol min
F F
=
= = =
= = = =
= = =
=0, 0,
09 *0.96 ; 1.135feed feedA A
F F kmol min= =
Feed Stream T=750C
Outlet Stream T=750C
1
2
1
2
3 2 5 3 2 2 5 2
0
3 3 31 2
0.5 0.5 3 0.5 0.5 31 2
75 , 1.1
22.63*10 1 , 1.55*10 .
* ; 22.63*10 * 1.55*10
k
k
k
k
reaction B
A A B C D A A B C D
CH COOH C H OH CH CO C H H O
A B C D
T C
k min k m kmol min
r k C C k C C r C C C C
θ− −
− −
+ +
+ +
= =
= =
− = − − = −
Reference 8
Figure 1. A typical CSTR
- 15 -
( ) ( )
0
0
0
0
0 0, 0, 0,
2 0, 0
2
,
,
1.1 1.09*1.1 1.199
, 1.09 1.1 0.416 ; 0.745
*0.965 , 1.199 *0.965 , 1.242
1.135 1.09 0.0454feed feed feed
feed
BB B
A
B B B BA
B B B B
H O from AcA A A
H O fro
FF kmol min
F
F F x F F kmol min
F F F F kmol min
F F F kmol min
F
θ
θ
= = = =
= − = − =
= = =
= − = − =
( ) ( )
0, 0
2 2 2 0 2
0 0
0
, , , ,
1.242 1.199 0.0435
0.0454 0.0435 ; 0.0889
; 0.0889 1.09*0.416 ; 0.542
1 , 1.09 1 0.416 ; 0.
feedm EtOH B B
H O feed H O from AcA H O from EtOH D H O feed
D D DD A
A A AA
F F kmol min
F F F F F kmol min
F F F x F F kmol min
F F x F F
= − = − =
= + = + = =
= + = + =
= − = − = 636
, 0.636 0.745 0.453 0.542 ; 2.376Total A B C D Total Total
kmol min
F F F F F F F kmo lmin= + + + = + + + =
( )
( ) ( )
0
0 0
0 0 0
0
0
0
0 0
0
0
0 , ,
33
; ,
, ,* *1
0.08891.1 , 0.08151.09
1050 ; 17.48560.05
1 17.485 1 0.416 ; 10.211
A
A
A A AA A A
w A A w AA
DB D
A
A A
A AA
F xDesign Equaition of the CSTR V in liquid phase
r
F FC C C
F M M
F
F
kg mC C kmol mkg kmol
C C x C k
ν ν
ρν ρ
θ θ
= =−
= = =
= = = =
= =
= − = − =
( ) ( )
( ) ( )
0
0
0
3
3
3
3
3 0.5 0.5 3
3
17.485 1.1 0.416 ; 11.959
17.485*0.416 ; 7.273
17.485 0.0815 0.416 ; 8.698
22.63*10 *10.211 *11.959 1.55*10 *7.273*8.698
0.152 .
B B BA
C CA
D D DA
A
A
mol m
C C x C kmol m
C C x C kmol m
C C x C kmol m
rr kmol m mi
θ
θ
− −
= − = − =
= = =
= + = + =
− = −
− = n
See in Table 7
See in Table 8
Reference 7
- 16 -
3
3
2 3
1.09*0.416 ; 2.9830.152
1.15 , 1.3 3
1.15*2.983 ; 3.43
; 3.43 *1.3*4 4
1.497 , 1.5
1.3*1.5 ; 1.95
1.5 ; 0.53
1 ; 1.5*3 4.3
liquid liquid
tank liquidag
tank tank
tank
ag ag
V V m
DAssuming V V H D andd
V V m
V D H D
D m D mH H m
d d m
E ED
π π
= =
= = =
= =
= =
=
= =
= =
= = =
5 m
Calculation of Motor Power
( )
( )
2 26
4
3 5
3 5
120 2 , 2 , 0.9 , 1.3
878.489*2*0.5Re Re 1*104.29*10
7 ;
7* *
7*878.489*2 *0.5
1537.35
2*1537.35 3074.7
act
mix agc
mix
P c P
Pmix ag
act
Assuming N rpm rps P P safety factor
Nd
From N vs Re figure N is found asPNN d
P
P WP W
η
ρµ
ρ
−
= = = = =
= =
= =
=
=
= =
( )* 3074.7*1.30.9
4441.23 4.441
actmotor
motor
P safety factorP
P W kWη
= =
= =
See in Table 2
Reference 4
See in Table 8
See in Table 2
- 17 -
Design of Jacket by Heating Process
Total energy balance between reaction zone and jacket;
, (75 75) 0
; 0out in rxn
out in rxn
Q H H H TSo H H Q H= ∆ −∆ + ∆ ∆ = − =
∆ = ∆ = ⇒ = ∆
[ ] [ ]{ }
0
, ,
, ,
, ,
3
25ˆ ˆ486180 277630ˆ ˆ463200 285840ˆ ˆ ˆ
1.09 10ˆ 463200 285840 486180 277630 * *1
rxn R P f
f A f B
f C f D
f f Product f Reactant
f
A B C D
H H H H
At C
H J mol H J mol
H J mol H J mol
H H H
kmol molJHmol min kmol
+ +
∆ = ∆ + ∆ + ∆
∆ = − ∆ = −
∆ = − ∆ = −
∆ = ∆ −∆
∆ = − − − − −
3
0
, ,
, ,
1*60
268.321*10
75 25 502
2160 . 2670 .
2020 . 4180 .
f
Avg
P A P B
P C P D
mins
H W
At T C
C J kg K C J kg K
C J kg K C J kg K
∆ =
+= =
= =
= =
Hot oil Tin=2000C
Hot oil Tout= ?
Feed Stream Tinitial=750C
Outlet Stream Tfinal=750C
ˆRH∆
ˆfH∆
ˆPH∆
Q 750C 750C
250C 250C
Figure 3. Hypotetical step of ∆Hrxn
Figure 2. A typical CSTR with Jacket
See in Table 3
- 18 -
( )
3
2160 *60.05 *1.09. 1* 25 75 *
602670 *46.07 *1.199
.
240.722 *10
2160 *60.05 *0.636.
2670 *46.07 *0.7.
R
R
P
J kg kmolkg K kmol min minH K
sJ kg kmolkg K kmol min
H W
J kg kmolkg K kmol min
J kgkg K kmol
H
∆ = − +
∆ = −
+
∆ = ( )
( )
3
3 3
451* 75 25 *60
2020 *88.1 *0.453.
4180 *18 *0.542.
246.276*10
240.722 246.276 268.321 *10 273.875*10
P
rxn
kmolmin minK
sJ kg kmolkg K kmol min
J kg kmolkg K kmol min
H W
H W
Q
−
+
+
∆ =
∆ = − + + =
= ∆ 3273.875*10rxnH W=
( )
,
2 2
2 2
2
20
,
40.6 , 1.5*10 2.3*10
2* 1.5 2*1.5*10 ; 1.53
2* 1.5 2*2.3*10 ; 1.576
oil P oil
oil oil
jo ji
shell jacket
ji shell ji
jo ji jacket j
Q m C T
m mm AA D D
Assuming m s t m and t m
D D t D m
D D t D m
ρ ρρυ υ π
υ − −
−
−
= ∆
= = =−
= = =
= + = + =
= + = + =
See in Table 11
- 19 -
( )
( )
0
3,
2 2
3
0 0
200
2204 . , 897.6
897.60.6 ; 60.431.576 1.53
460.43*2204* 273.875*10
2.056 ; 200 197.944
in
P oil oil
oiloil
out out
At T CC J kg K kg m
m m kg s
Q T
T C T T T C
ρ
π
=
= =
= =−
= ∆ =
∆ = ∆ = − =
( ) ( )( ) ( )
22 2 2 2
2 2 2 2
60.43 ; 538.7950.785 0.785 1.576 1.53
1.576 1.53; 0.093
1.53
oil
jo ji
jo jieq eq
ji
mG G kg mD D
D Dd d m
D
= = =− −
− −= = =
For calculation of the properties of hot oil average temperature must be used; 0
0 0
3,
0.81 3
,
3
200 197.944 198.9722
198.972 200
0.73*10 . , 0.109 . 2204 .
**0.027* *
0.093 2204*0.73*100.027*0.109 0.10
Avg
Avg
oil oil P oil
i eq eqP oil oil
oil oil oil
i
T C
At T C C
Pa s k W m K and C J kg K
h d d GCk k
h
µ
µµ
−
−
+= =
=
= = =
=
=
1 3 0.8
3
2
0.093*538.795*9 0.73*10
574.482 .ih W m K
−
=
For the calculation of ho density, viscosity, specific heat capacity and thermal conductivity correlations were made for each component from References 3.
4
3
0.2529
2 311 2 3 4
1 1
2
0
33481 1591.95
3
,
751.4486 16.4725
0.25892
60.0516.4725 * ; 989.211
C waterTC
A
A A
C for all components except water For water C C T C T C T
C
At Ckmolm
kgkmolm kmol
ρ ρ
ρ
ρ ρ
+ −
+ −
= = + + +
= =
= = 3kg m
Density Correlation;
For other components the density correlation results are shown in Table 4.
See in Table 11
- 20 -
3
* * * *0.636 0.745 0.453 0.542989.211* 738.34* 831.61* 960.76*2.378 2.378 2.378 2.378
878.489
mix A A B B C C D D
mix
mix
x x x x
kg m
ρ ρ ρ ρ ρ
ρ
ρ
= + + +
= + + +
=
[ ]( )
( )
521 3 4
0
0
4
exp *ln * ,
751212.3exp 9.03 0.322 *ln 348 0*348
3485.93*10 .
Ci
A
A
CC C T C T i for each component T KT
At C
Pa s
µ
µ
µ −
= + + +
= − + + − +
=
Viscosity Correlation;
For other components the viscosity correlation results are shown in Table 5.
( ) ( )
( ) ( )
1 3 1 31 3 1 3 1 3 4 4
1
1 3 1 34 4
4
, 0.27* 5.93*10 0.31* 4.624*10
0.19* 2.58*10 0.23* 3.8*10
4.29*10 .
n
mix i i mixi
mix
x
Pa s
µ µ µ
µ
− −
=
− −
−
= = +
+ +
=
∑
0.27*0.1714 0.31*0.12395 0.19*0.14229 0.23*0.16555
0.15 .
mix A A B B C C D D
mix
mix
k x k x k x k x kkk W m K
= + + +
= + + +
=
Thermal Conductivity Calculation;
( )
,
, , , , , , , , ,
,
,
0.636*60.05 0.310.636*60.05 0.745*46.07 0.453*88.1 0.542*18
9
* * * *
2.28*0.31 2.96*0.28 2.12*0.32 4.19*0.09 *1000
2591.
w A
P mix P A w A P B w B P C w C P D w D
P mix
P mix
x
Other values are shown in TableC C x C x C x C x
C
C
= =+ + +
= + + +
= + + +
= 1 .J kg K
Heat Capacity Calculation;
See in Table 6
- 21 -
2 30.25 2,
2 320.25
2
0
0 0
* **0.55* *
1200.5 * *878.489*1.5 2591.1*0.000429 600.55* *0.15 0.15 0.000429
921.84 .
1 1 1 1 1 1,921.84 574.
ag mixP mix mixo
mix mix mix
o
o
o i i
d NCh Dk k
rpsh
h W m K
DU h h D U
ρµµ
=
=
=
= + = +
( )( )
20
00 0 ln 1
02
0ln
30,
20,
0,
20,
1.576*482 1.53
342.32 .
200 75 125
197.944 75 122.944
123.969
273.875*10 342.32* *123.969
6.36
*1.5*1.95
9.189
req
req
calc
calc
U W m K
Q U A T T C
T C
T CA
A m
A DH
A m
π π
=
= ∆ ∆ = − =
∆ = − =
∆ =
=
=
= =
=
A0,calc >A0,req
So; the jacket satisfies our reactor design.
Reference 5
See in Table 11
- 22 -
Design of Coil by Heating Process
( )
( )
0
2 2
,
3
0 0
3 200
0.0409 , 0.0482
897.6 30.0482
4 43.536
3.536*2204* 273.875*10
35.134 ; 200 164.866
200 164.866 1822
in
i o
oil oil
o
oil
oil P oil
out out
Avg
Assume m s and T C
d m d mm m m
A d
m kg s
Q m C T
Q T
T C T T T C
At T
υ
ρ ρυ π π
= =
= =
= = = =
=
= ∆
= ∆ =
∆ = ∆ = − =
+= =
0
3
3,
0.40.8,0
0.8
3
.433
0.110 . , 910.248
2147.464 . , 0.86*10 .
** *0.023* *
0.0482 2147.0.0409*3*910.2480.023* *0.110 0.86*10
oil oil
P oil oil
P oil oili i oil
oil oil oil
i
C
k W m K kg m
C J kg K Pa s
Ch d dk k
h
ρ
µ
µυ ρµ
−
−
= =
= =
=
=
0.43
2
464*0.86*100.110
2001.1634 .ih W m K
−
=
Feed Stream Tinitial=750C
Outlet Stream Tinitial=750C
Hot Oil Tin=2000C
Hot Oil Tout= ?
Figure 4. A typical CSTR with coil
Reference 2
See in Table 1
- 23 -
2
0.04821 3.5 2001.1634* 1 3.50.0409
10266.838 .
oic i
i
ic
dh hd
h W m K
= + = + =
0.621 3 2,
0.6221 3
2
0
0 0
* **0.87* *
1200.5 * *878.489*1.5 2591.1*0.000429 600.87* *0.15 0.15 0.000429
903.282 .
1 1 1 1 1 1,903.282 1
ag mixP mix mixo
mix mix mix
o
o
o ic i
d NCh Dk k
rpsh
h W m K
dU h h d U
ρµµ
=
=
=
= + = +
( )( )
20
00 0 ln 1
02
0ln
30,
20,
'
0.0482*0266.838 0.0409
818.318 .
200 75 125
164.866 75 89.866
106.468
273.875*10 818.318* *106.468
3.143
20
2*20*10
req
req
U W m K
Q U A T T C
T C
T CA
A m
We put the coils cm apart from the reactor wallsD D
=
= ∆ ∆ = − =
∆ = − =
∆ =
=
=
= − 2 '
'
0, 0
0,
0, 0,
1.5 0.4 1.1
*1.1 3.45
* *0.0482*3.45*
1.914*
6
calc
calc
calc req
D mPerimeter of one coil P D mA d P n n
A n
if A A
n coils
π π
π π
− = − =
= = = =
= =
=
=
=
If the space between the coils is 6 cm, the space from bottom of reactor is 45 cm, and the comparison of height of the tank with the height of the coil is shown below;
( )( ) ( ) ( )( )
0
2 2
* * 1
45*10 0.0482*6 6*10 * 6 1
1 1.95
coil bottom SpacesBetweenCoil
coil
coil tank
H H d n H n
H
H m H m
− −
= + + −
= + + −
= < =
So; the coil satisfies our reactor design like mentioned in the discussion part.
Reference 2
See in Table 1