Group 10
Process Control and Instrumentation (SKTK 3564-03)
b) A CSTR, shown in Figure 2, contains component A which reacts to form component B.
The inlet contains component A only, with concentration cAi kmol/liter. List and label all
the variables. Because of the reactor configuration, the volume of liquid in the reactor do
not change even when the inlet flow changes. Derive the model that describes the change
in the concentration of A and temperature in the reactor. .
Fin
Assumptions
1)
2)
Volume
Heat
:
is constant
loss is
Fout
dddfso dd¥=O
,
,
negligible
3) Perfect mixing
( Exit temperature
A
Tank
=
4) Irreversible reaction
temperature)
r
,
KCA
=
pad
Q
component Balance
DNA
at
Fi
=
F
-
r✓
-
=
←
F. Cao
FCA
-
-
Using chain rule
( doff)
t
CA
Hin t Qin
dimwitted)
=
pVte =p F. Cp
dt
VCT tree )
-
in Cp Cti
)
NF
=
KCA
=
Fi Cao
=
-
dat
-
Fi Cti
-
F(T
( ti
Tres )
+
KCAV
-
Kca
-
Hout
-
Ein
=
-
-
Tret )
-
#
Fast
-
-
in Cp ( T
p
Fa
Tre f )
t
p
-
Cp (T
t
consumed
H
RV Hrxn
t
Tree )
tout
-
-
dts
FCA
:
Energy accumulation
ddtt
Figure 2
F
:
CA#⇒°
Balance
=
Q
KCAV
=
Energy
Fout
,
;
doff ( FiCm )
=
Fi
=
r
d CAV
✓
Fin
:
h
B
&
reaction
First order
k
;
-
-
r
=
=
Tree )
Tree ) t
¥
,
t
t
Generation
in
KCA
Cpd T
t
t Q
Q
t
KCA V
KCAV Horan ; in
M
KCAVH an
Hrxn
-pcp
;
F
-
Tree
f
=
-
SPF
=P
V
Fa
0
Pcp
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