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-rwxr-xr-x839/CH22/EX22.1/Example_22_1.sce39
-rwxr-xr-x839/CH22/EX22.2/Example_22_2.sce41
-rwxr-xr-x839/CH22/EX22.3/Example_22_3.sce90
-rwxr-xr-x839/CH22/EX22.4/Example_22_4.sce60
-rwxr-xr-x839/CH22/EX22.5/Example_22_5.sce99
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diff --git a/839/CH22/EX22.1/Example_22_1.sce b/839/CH22/EX22.1/Example_22_1.sce
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+//clear//
+clear;
+clc;
+
+//Example 22.1
+//Given
+Dp = 1; //[in.]
+vdot = 25000; //[ft^3/h]
+T = 68; //[F]
+P = 1; //[atm]
+ya = 0.02;
+Mair = 29;
+Mg = 17;
+//Solution
+//The average molecular weiht of the entering gas
+M = (1-ya)*Mair+ya*Mg;
+rho_y = M*492/(359*(460+68)); //[lb/ft^3]
+
+//(a)
+//Using Fig. 22.5, when Gy =Gx;
+Gy = 0.472; //[lb/ft^2-s]
+Gx = Gy; //[lb/ft^2-h]
+des_value = Gy/2; //[lb/ft^2-h]
+mdot = vdot*rho_y/3600; //[lb/s]
+//Cross-sectional area of the tower
+S = mdot/des_value //[ft^2]
+//the diameter of the tower is
+Dtower = sqrt(4*S/%pi); //[ft]
+disp('ft',Dtower,'The tower diameter is');
+
+//(b)
+h = 20; //[ft]
+//Using Fig 22.4, the pressure drop for
+Gy = 850; //[lb/f^2-h]
+Gx = Gy;
+delta_P = 0.35; //[in.] (H2O/ft)
+//The total pressure drop
+Pt = delta_P*h; //[in.] H2O
+disp('in. H2O' ,Pt,'The pressure drop would be');
diff --git a/839/CH22/EX22.2/Example_22_2.sce b/839/CH22/EX22.2/Example_22_2.sce
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+//clear//
+clear;
+clc;
+
+//Example 22.2
+//Given
+Dp = 1; //[in.]
+vdot = 25000; //[ft^3/h]
+T = 68; //[F]
+P = 1; //[atm]
+ya = 0.02;
+Mair = 29;
+Mg = 17;
+//Solution
+//The average molecular weiht of the entering gas
+M = (1-ya)*Mair+ya*Mg;
+rho_y = M*492/(359*(460+68)); //[lb/ft^3]
+rho_x = 62.3; //[lb/ft^3]
+//(a)
+//Using Fig.(22.8), from Example 22.1 A = Gx/Gy = 1 and
+//Let
+A = 1;
+B = A*sqrt(rho_y/rho_x);
+//Form Fig 22.8, the superficial vapor velocity at flooding
+//is uof*sqrt(rho_y/(rho_x-rho_y))=0.11, therefore
+uof = 0.11/sqrt(rho_y/(rho_x-rho_y)); //[m/s]
+//The allowable vapor velocity
+uo = uof*0.5; //[m/s]
+uo = uo*3.28; //[ft/s]
+//the corresponding mass velocity
+Gy = uo*rho_y; //[lb/ft^2-s]
+//The allowable mass velocity in the example was 0.236 lb/ft^2-s.
+//The increase by using structured packing is
+increase = (Gy/0.236)-1;
+disp(increase*100,'The percent increase in mass velocity is');
+
+//(b)
+//The pressure drop
+delta_P = 20*1.22*(0.5/0.9)^1.8; //[in. H2O]
+//This is 1.2 times the pressure drop of 7 in.H2O in the Intolax saddles.
+disp('The pressure drop will be greater than Intolax Saddles')
diff --git a/839/CH22/EX22.3/Example_22_3.sce b/839/CH22/EX22.3/Example_22_3.sce
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+//clear//
+clear;
+clc;
+
+//Example 22.3
+//Given
+vdot = 4500; //[SCFM]
+yin = 0.06;
+yout = 0.0002;
+P = 1; //[atm]
+Tiy = 20; //[C]
+Tix = 25; //[C]
+
+//Solution
+//From Perry
+x = [0.0308,0.0406,0.0503,0.0735]';
+y20 = [0.0239,0.0328,0.0417,0.0658]';
+y30 = [0.0389,0.0528,0.0671,0.1049]';
+y40 = [0.0592,0.080,0.1007,0.1579]';
+deltaH = -8.31*10^3; //[cal/g mol], fro NH3=NH3(aq)
+//Basis:
+gas_in = 100; //[g mol dry]
+air_in = (1-yin)*gas_in; //[mol]
+NH3_in = yin*gas_in; //[mol]
+H2O_in = 2.4; //[mol]
+air_out = air_in; //[mol]
+//The moles of NH3 in the outlet gas,
+NH3_out = air_out*(yout/(1-yout)); //[mol NH3]
+//The amount of NH3 absorbed
+NH3_abs = NH3_in-NH3_out; //[mol]
+//Heat Effects:
+//The heat of absorption
+Qa = -NH3_abs*deltaH; //[cal]
+//Sensible heat changes in the gas are
+Qair = air_in*7*5; //[cal]
+QH2O =H2O_in*8*5; //[cal]
+Qsy = 3290+96; //[cal]
+//The amount of vaporization of water from the liquid
+pH2O_20 = 17.5; //[mm Hg], at 20C
+pH2O_25 = 23.7; //[mm Hg], at 25C
+H2O_inlet = gas_in*(pH2O_20/742.5); //[mol]
+H2O_outlet = 94.02*(pH2O_25/736.3); //[mol]
+//The amount of water vaporized
+H2O_vaporized = H2O_outlet-H2O_inlet; //[mol]
+deltaHv = 583; //[cal/g]
+Qv = deltaHv*H2O_vaporized*18.02; //[cal]
+//From Eq.(22.31)
+Qsx = Qa-(Qv+Qsy); //[cal]
+
+Cp = 18; //[cal/g-mol-C]
+xmax = 0.031;
+Tb = 40; //[C]
+Ta = 25; //[C]
+err =1;
+while(err>0.01)
+ Lb = NH3_abs/xmax;
+ Tbnew = Qsx/(Lb*Cp)+Ta;
+ err = Tb-Tbnew;
+ Tb=Tbnew;
+ xmax = xmax+0.002;
+end
+Lmin = Lb-NH3_in; //[mol H2O]
+La = 1.25*Lmin; //[mol]
+Lb = La+NH3_in; //[mol]
+//The temperature rise of the liquuid is
+Tb = Qsx/(Lb*Cp)+Ta; //[C]
+xb = NH3_in/La; //[C]
+ystar = 0.044;
+//Assuming temperature to be linear function of x, so
+T = 30;
+//x = 0.0137;
+//Using the data given for 30C and interpolating to get the
+//initial slope for 25 and the final value ystar for 35, the
+//euilibrium line is drawn
+y = [0.06, 0.03,0.01,0.0002]';
+ystar = [0.048,0.017,0.0055,0]';
+delta_y = y-ystar;
+delta_yL = [0.0125, 0.0080,0.00138]';
+delta_NOy = [2.4,2.5,7.1]';
+NOy = sum(delta_NOy);
+disp(NOy,'The value of NOy is');
+
+
+
+plot(x,y20,x,y30,x,y40);
+xgrid();
+xlabel('x');
+ylabel('y');
+legend('20C','30C','40C');
+title('x vs y of NH3 at different temperatures');
diff --git a/839/CH22/EX22.4/Example_22_4.sce b/839/CH22/EX22.4/Example_22_4.sce
new file mode 100755
index 000000000..46c73f521
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+++ b/839/CH22/EX22.4/Example_22_4.sce
@@ -0,0 +1,60 @@
+//clear//
+clear;
+clc;
+
+//Example 22.4
+//Given
+ieee();
+H = 0.0075; //[TCE]
+T = 20; //[C]
+P = 1; //[atm]
+wa = 6*10^-6; //[g]
+Ca = 6; //[ppm]
+wb = 4.5*10^-9 //[g]
+M = 18;
+
+//Solution
+m = H/P*10^6/M;
+//With this large value of m, the desorption is liquid-phase controlled.
+//At the minimum air rate, the exit gas will be in equilibrium with the
+//incoming solution.
+MTCE = 131.4;
+j = 1.5;
+for i = 1:7
+xa = wa/MTCE*M;
+ya = m*xa;
+//Per cubic meter of solution fed, the TCE removed is
+VTCE = 10^6*(wa-wb)/MTCE; //[mol]
+//The total amount of gas leaving is
+V = VTCE/ya; //[mol]
+Fmin = V*0.0224; //[std m^3], as 1 gmol = 0.0224 std m^3
+Vmin = Fmin*j;
+//Density at the standard conditions,
+rho = 1.259; //[kg/m^3],
+//so the minimum rate on a mass basis is,
+//Let A = (Gy/Gx)min
+A = Vmin*rho/1000; //[kg air/kg water]
+//If the air rate is 1.5 times the minimum value, then
+ya = ya/j;
+xastar = ya/m;
+Castar = xastar*MTCE/M *10^6; //[ppm]
+delta_Ca = Ca-Castar;
+
+//At bottom
+Cb = 0.0045; //[ppm]
+Cbstar = 0; //[ppm]
+delta_Cb = Cb-Cbstar; //[ppm]
+delta_CL = (delta_Ca-delta_Cb)/log(delta_Ca/delta_Cb); //[ppm]
+Nox(i) = (Ca-Cb)/delta_CL;
+j = j+0.5;
+end
+
+Hox = 3; //[ft]
+Z = Hox*Nox; //[ft]
+//Going from 1.5 to 2Vmin or from 2 to 3Vmin decreases the tower height
+//considerably, and the reduction in pumping work for water is more than
+//the additional energy needed to force air through the column. Further
+//increase in V does not change Z very much, and the optimum air rate is
+//probably in the range 3 to 5Vmin./
+
+disp(Nox,'Number of Transfer units with minimum air rates')
diff --git a/839/CH22/EX22.5/Example_22_5.sce b/839/CH22/EX22.5/Example_22_5.sce
new file mode 100755
index 000000000..76d8d4dfa
--- /dev/null
+++ b/839/CH22/EX22.5/Example_22_5.sce
@@ -0,0 +1,99 @@
+//clear//
+clear;
+clc;
+
+//Example 22.5
+//Solution
+//Equlibrium data are shown in Fig.22.22
+//By a heat balance similar to that of Eample 22.3
+//The temperature rise of the liqui was estimated
+//to be
+delta_T = 12.5; //[C]
+//Basis:
+dry_gas_in = 100; //[mol]
+sol_in = 140; //[mol]
+N2_in = 87; //[mol]
+CO2_in = 10; //[mol]
+EO_in = 3; //[mol]
+N2_out = 87; //[mol]
+CO2_out = 10; //[mol]
+EO_out = 3*0.02; //[mol]
+IN = N2_in+CO2_in+EO_in; //[mol]
+OUT = N2_out+CO2_out+EO_out; //[mol]
+//Assuming negligible CO2 absorption and neglect effect of H2O on
+//gas composition.
+//At top:
+xt = 0.004;
+yt = EO_out/OUT;
+//Moles of EO absorbed
+EO_abs = 3*0.98; //[mol]
+//Moles of EO absorbed in water
+EO_H2O = 140*0.0004; //[mol]
+//At bottom:
+xb = (EO_abs+EO_H2O)/(140+EO_abs);
+yb = 0.03;
+//From Fig 22.22
+y = [0.03,0.015,0.005,0.0006]';
+delta_y1 = [0.008,0.0006,0.0024,0.0003]';
+
+for i = 1:length(y)-1
+ delta_y = y(i)-y(i+1);
+ delta_yL = (delta_y1(i)-delta_y1(i+1))/log(delta_y1(i)/delta_y1(i+1));
+ Noy1(i) = delta_y/delta_yL;
+end
+Noy = sum(Noy1);
+
+//Column diameter:
+//Using generalize pressure-drop correlation, Fig.22.6
+//Based on the inlet gas,
+Mbar = 0.87*28+0.1*44+0.03*44;
+//At 40C,
+rho_y = 30.1/359*20*273/313 //[lb/ft^3]
+rho_x = 62.2; //[lb/ft^3]
+//Let A = Gx/Gy*sqrt(rho_y/(rho_x-rho_y))
+A = 1.4*18/(1*30.1)*sqrt(rho_y/(rho_x-rho_y));
+//From Fig. 22.6, for
+delta_P = 0.5; //[in.H2O/ft]
+//Let B = Gy^2*Fp*mux^0.1/(rho_y*(rho_x-rho_y)*gc)
+B = 0.045;
+//From Table 22.1,
+Fp = 40;
+mu = 0.656; //[cP]
+//so
+Gy = sqrt(B*(rho_y)*(rho_x-rho_y)*32.2/(Fp*mu^0.1)); //[lb/ft^2-h]
+//or
+Gy = Gy*3600; //[lb/ft^2-s]
+Gx = 1.4*18/(1*Mbar)*Gy; //[lb/f^2-s]
+//For a feed rate
+F = 10000*Mbar; //[lb/h]
+S = F/Gx; //[ft^2]
+D = sqrt(S*4/%pi); //[ft]
+//Column heigth:
+//From Fig. 22.20 at Gy = 500 and Gx = 1500
+Hy_NH3 = 1.4; //[ft]
+mu_40 =0.0181*10^-2; //[P], Appendix 8
+Dv = 7.01*10^-3; //[cm^2/s], from Eq.(21.25)
+rho = 2.34*10^-2; //[lb/ft^3]
+Nsc = mu_40/(rho*Dv);
+//Form Table 22.1,
+fp = 1.36;
+Hy_EO = 1.4*(1.1/0.66)^0.5*1/1.36*(Gy/500)^0.3*(1500/Gx)^0.4; //[ft]
+//Form Fig. 22.19,
+Hx_O2 = 0.9; //[ft]
+Gx1 = 1500;
+mu1 = 0.00656; //[P]
+rho1 = 1; //[lb/ft^3]
+//Using Eq.(21.28)
+Dv1 = 2.15*10^-5; //[cm^2/s]
+Nsc1 = mu1/(rho1*Dv1);
+//Using Eq.(22.35), with the correction factor fp and Nsc = 381,
+//for O2 in water at 25 C
+Hx_EO = Hx_O2*(Gx/(mu1*100)/(Gx1/0.894))^0.3*(Nsc1/381)^0.5/1.36; //[ft]
+//From Fig 22.22, the average value of m
+m = 1.0;
+//From Eq.(22.30)
+HOy = 1.71+(1*0.96)/1.4; //[ft]
+
+disp(NOy,'number of transfer units required')
+disp('ft',D,'diameter of the column')
+disp('ft',HOy,'packing height')
diff --git a/839/CH22/EX22.6/Example_22_6.sce b/839/CH22/EX22.6/Example_22_6.sce
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--- /dev/null
+++ b/839/CH22/EX22.6/Example_22_6.sce
@@ -0,0 +1,56 @@
+//clear//
+clear;
+clc;
+
+//Example 22.6
+//Solution
+rho_m = 62.2/18; //[mol/ft^3]
+//kya = 0.025*Gy^0.7*Gx^0.25
+H2ObySO2 = 2*0.98964/0.01036;
+//and
+xb = 1/(H2ObySO2+1);
+//The molal mass velocity of the feed gas Gm is
+Gm_in = 200/29*(1/0.8); //[mol/ft^2-h]
+SO2_in = Gm_in*0.2; //[mol/ft^2-h]
+Air_in = Gm_in*0.8; //[mol/ft^2-h]
+Air_out = Air_in; //[mol/ft^2-h]
+SO2_out = Air_out*(0.005/(1-0.005)); //[mol/ft^2-h]
+SO2_abs = SO2_in-SO2_out; //[mol/ft^2-h]
+H2O_in = H2ObySO2*SO2_abs; //[mol/ft^2-h]
+//Operating line
+x = 0:6;
+x = x/10^3;
+A = x./(1-x);
+B = H2O_in/Air_in*A+(0.005/0.995);
+y = B./(B+1);
+plot(x,y)
+xgrid();
+xlabel('x');
+ylabel('y');
+//legend('20C','30C','40C');
+title('x vs y');
+Gxbar = H2O_in*18.02+SO2_abs*64.1/2; //[lb/ft^2-h]
+kxa = 0.131*Gxbar^0.82; //[mol/ft^3-h]
+//The gas film coefficients are calculated for the bottom
+//and the top of the tower:
+//At bottom:
+Gy_B = (Air_in*29)+(SO2_in*64.1); //[lb/ft^2-h]
+kya_B = 0.025*Gy_B^0.7*Gx^0.25; //[mol/ft^3-h]
+//At top:
+Gy_T = (Air_out*29)+(SO2_out*64.1); //[lb/ft^2-h]
+kya_T = 0.025*Gy_T^0.7*Gx^0.25; //[mol/ft^3-h]
+//Assuming
+yLbar = 0.82
+C = kxa*yLbar/kya_B;
+//a line from (yb,xb) with a slope of -C, gives
+yi = 0.164;
+yLbar = 0.818;
+m = 20.1
+Kya_prime = 1/(yLbar/kya_B+m/kxa); //[mol/ft^3-h]
+//The fraction of the total resistance that is in the liquid is
+Rf = m/kxa/(1/Kya_prime);
+//For different values of y1
+y1 =[0.2,0.15,0.1,0.05,0.02,0.005]';
+delta_y1 = [0.103,0.084,0.062,0.034,0.015,0.005]';
+y1i = [0.164,0.118,0.074,0.034,0.012,0.002]';
+delta_yi = y1-y1i;