Chapter 7 : Design for Parallel Reactions

Example 7.2 page no : 159

In [2]:
import math 
from scipy.integrate import quad 

# Variables
#Initial Concentration(mol/litre)eactant in combined feed
CAo = 10.
CBo = 10. 
XA = 0.9;             # conversion
CAf = CAo*(1-XA);
CA = CAf;

# Calculations
def f4(CA): 
	 return 1./(1+CA**0.5)

Qp = (-1./(CAo-CAf))* quad(f4,CAo,CAf)[0]

CRf = 9*Qp;
CSf = 9*(1-Qp)
# Results
print " Part a"
print " For Plug Flow"
print " Concentration of R in the product stream is %.2f mol/litre"%(CRf)
print " Csf is %.2f mol/litre"%(CSf)

Qm = CA/(CA+CA**1.5);
CRf = 9*Qm;
Csf = 9*(1-Qm)
print " Part b"
print " For Mixed Flow"
print " Concentration of R in the product stream is %.2f mol/litre "%(CRf)
print " Csf is %.2f mol/litre"%(Csf)

CAo = 19.
CB = 1;

def f5(CA): 
	 return CA/(CA+CB**1.5)

Q = -1./(CAo-CAf)* quad(f5,CAo,CAf)[0]
CRf = 9*Q;
Csf = 9*(1-Q)
print " Part c"
print " For Plug flow A Mixed flow B"
print " Concentration of R in the product stream is %.2f  mol/litre"%(CRf)
print " Csf is %.2f mol/litre"%(Csf)
print ('The result for plug flow varies as there seems to be typographical error in integration done in book')

 Part a
 For Plug Flow
 Concentration of R in the product stream is 2.86 mol/litre
 Csf is 6.14 mol/litre
 Part b
 For Mixed Flow
 Concentration of R in the product stream is 4.50 mol/litre 
 Csf is 4.50 mol/litre
 Part c
 For Plug flow A Mixed flow B
 Concentration of R in the product stream is 7.85  mol/litre
 Csf is 1.15 mol/litre
The result for plug flow varies as there seems to be typographical error in integration done in book

Example 7.3 page no : 162

In [3]:
import math 
from scipy.integrate import quad 

# Variables
CAo = 2;          # decomposition of A
CA = 0.5;
CAf = 0.;

Csf = (CAo-CA)*2*CA/(1+CA)**2;

print " Part a"
print " For Mixed Flow Reactor"
print " Maximum expected Cs is %.3f"%(Csf)

# Calculations
def f12(CA): 
	 return 2*CA/(1+CA)**2

Csf = -1* quad(f12,CAo,CAf)[0]

# Results
print " Part b"
print " For Plug Flow"
print " Maximum expected concentration of S is %.3f "%(Csf)

CA = 1.;
Csf = (CAo-CA)*2*CA/(1+CA)**2;

print "Part c"
print " For MFR with separation and recycle" 
print " Concentration of Csf is %.2f"%(Csf)

 Part a
 For Mixed Flow Reactor
 Maximum expected Cs is 0.667
 Part b
 For Plug Flow
 Maximum expected concentration of S is 0.864 
Part c
 For MFR with separation and recycle
 Concentration of Csf is 0.50

Example 7.4 page no : 164

In [5]:
import math 
from scipy.integrate import quad 

# Variables
CAo = 2.     # based on example 7.3
CA = 1.
Q = 0.5

# Calculations
Cs1 = Q*(CAo-CA);

def f6(CA): 
	 return 2*CA/(1+CA)**2

Cs2 = -1* quad(f6,1,0)[0]

#Total amount of CS formed is
Cs = Cs1+Cs2;

# Results
print "Mixed flow followed by plug flow would be best"
print " Total amount of CS formed is %.3f mol/litre"%(Cs)

Mixed flow followed by plug flow would be best
 Total amount of CS formed is 0.886 mol/litre
In [5]: