Chapter 6 : Design for Single Reactions

Example 6.1 page no : 125

In [1]:
# Variables
V1 = 50.       # volume liters
V2 = 30.       # volume liters
V3 = 40.;      # volume liters

# Calculations
VD = V1+V2;
VE = V3;
m = VE/VD
fr_D = 1./(1+m);

# Results
print " Fraction of feed going to branch D is %.3f "%(fr_D)

 Fraction of feed going to branch D is 0.667

Example 6.2 page no : 129

In [2]:
# Variables
kCot = 90.        # reactant
kCot = 180.       
X = 97.4;         # conversion

print " Part a"
print " The conversion in percentage is %.2f "%(X)
#For 90% Conversion & N = 2.from graph
kCot = 27.5;

# Calculations
ratio = 90*2/27.5;

# Results
print " Part b"
print " Treatment rate can be increased by  %.1f "%(ratio)

 Part a
 The conversion in percentage is 97.40 
 Part b
 Treatment rate can be increased by  6.5

Example 6.3 pageno : 144

In [3]:
%matplotlib inline

import math 
from numpy import *
from matplotlib.pyplot import *

# Variables
CAo = array([2,5,6,6,11,14,16,24]);         #mmol/m3
CA = array([0.5,3,1,2,6,10,8,4])            #mmol/m3
t = array([30,1,50,8,4,20,20,4])            #min
vo = 0.1                                    #m3/min

# Calculations
inv_rA = zeros(8)
for i in range(8):
    inv_rA[i] = t[i]/(CAo[i]-CA[i]);

for i in range(8):
    for j in range(i,8):
        if CA[i]>CA[j]:
            temp = CA[i];
            CA[i] = CA[j];
            CA[j] = temp;
            temp1 = inv_rA[i];
            inv_rA[i] = inv_rA[j];
            inv_rA[j] = temp1;

# Results
plot(CA,inv_rA)
plot(CA,inv_rA,"go")
suptitle("Arrangement with smallest volume")
xlabel("CA, m mol/m**3")
ylabel("-1/ra, m**3.min/m mol")
print ('From the graph,we can see that we should use plug flow with recycle')
CAin = 6.6;#mmol/m3
R = (10-6.6)/(6.6-1);
#V = t*vo = area*vo
V = (10-1)*1.2*vo;
vr = vo*R;
print " Part a"
print "  The vol of reactor is %.2f m**3"%(V)
print "  The recycle flow rate is %.4f "%(vr),
print "m3/min"

#Part b,from fig
t = (10-1)*10;
t1 = (10-2.6)*0.8;
t2 = (2.6-1)*10;
#For 1  math.tank
V = t*vo;
#For  2 math.tank
V1 = t1*vo;
V2 = t2*vo;
Vt = V1+V2;
print " Part b"
print "  For 1 tank volume is %.2f m**3"%(V)
print "  For 2 tank the volume is %.2f m**3"%(Vt)

print " Part c"
print (' We should use mixed flow followed by plug flow')
#For MFR
tm = (10-4)*0.2;
Vm = tm*vo;
#For PFR
tp = 5.8;#by graphical integration
Vp = tp*vo;
Vtotal = Vp+Vm;
print " For MFR volume is %.2f m**3"%(Vm)
print " For PFR volume is %.2f m**3"%(Vp)
print " Total volume is %.2f m**3"%(Vtotal),

Populating the interactive namespace from numpy and matplotlib
From the graph,we can see that we should use plug flow with recycle
 Part a
  The vol of reactor is 1.08 m**3
  The recycle flow rate is 0.0607  m3/min
 Part b
  For 1 tank volume is 9.00 m**3
  For 2 tank the volume is 2.19 m**3
 Part c
 We should use mixed flow followed by plug flow
 For MFR volume is 0.12 m**3
 For PFR volume is 0.58 m**3
 Total volume is 0.70 m**3
In [ ]: