6 files changed, 208 insertions, 0 deletions
diff --git a/839/CH27/EX27.1/Example_27_1.sce b/839/CH27/EX27.1/Example_27_1.sce
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+//clear//
+clear;
+clc;
+
+//Example 27.1
+//Given
+T = 60; //[F]
+wA = 0.30; //[MgSO4]
+wB = 0.70; //[H2O]
+
+//Solution
+//From Fig. 27.3 it is noted that the crystals are MgSO4.7H2O
+//and that the concentration of the mother liquid is
+xA = 0.245; //[anhydrous MgSO4]
+xB = 0.755; //[H2O]
+//Bases: 
+F_in = 1000; //[kg]
+H2O_in = F_in*wB; //[kg]
+H2O_evp = 0.05*H2O_in; //[kg]
+M1 = 120.4; //[MgSO4 molecular weight]
+M2 = 246.5; //[MgSO4.7H2O molecular weight]
+M2_in = wA*F_in*M2/M1; //[kg]
+H2O_free = F_in-H2O_evp-M2_in; //[kg]
+ML = 100; //[kg]
+M2_in100 = ML*xA*M2/M1; //[kg]
+H2O_free100 = ML - M2_in100; //[kg]
+M2_ML = M2_in100/H2O_free100*H2O_free; //[kg]
+FC = M2_in - M2_ML; //[kg]
+disp(FC,'kilograms of crystals obtained per kilogram of original mixture = ') 
diff --git a/839/CH27/EX27.2/Example_27_2.sce b/839/CH27/EX27.2/Example_27_2.sce
new file mode 100755
index 000000000..c50ab771e
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+//clear//
+clear;
+clc;
+
+//Example 27.2
+//Given
+//A = MgSO4, B = MgSO4.7H2O and C = H2O
+T = 120; //[F]
+wA = 0.325; 
+
+//Solution
+//From Fig 27.4
+//Enthalpy coordinate of the point wA
+H1 = -33; //[Btu/lb]
+//Enthalpy coordinate of the final magma at concentration wA
+H2 = -78.4; //[Btu/lb]
+//Per hundred pouds of original solution the change in enthalpy
+F = 100; //[lb]
+delta_H = F*(H1-H2); //[Btu]
+//Applying "center-of gravity principle" to 70 F isotherm in Fig. 27.3
+C_ML = 0.259;
+C_CRY = 0.488;
+//Crystals are
+Cry = F*(wA-C_ML)/(C_CRY-C_ML); //[lb/100lb slurry]
+//The heat evolved per ton of crystals is 
+H = delta_H/Cry*2000; //[Btu/ton]
+disp('Btu/ton',H,'The heat evolved per ton of crystals is')
diff --git a/839/CH27/EX27.3/Example_27_3.sce b/839/CH27/EX27.3/Example_27_3.sce
new file mode 100755
index 000000000..b8608e2d9
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+++ b/839/CH27/EX27.3/Example_27_3.sce
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+//clear//
+clear;
+clc;
+
+//Example 27.3
+//Given
+sigma = 2.5; //[erg/cm^3]
+T = 300; //[K]
+N = 6.0222*10^23;
+R = 8.3134*10^7; //[erg/g mol-K]
+//Solution
+M = 74.56; //[Molecular weight]
+rho = 1.988; //[g/cm^3]
+nu = 2;
+VM = M/rho //[cm^3/g mol]
+//Using Eq.(27.11)
+//Exponential term, excluding 's'
+A = 16*%pi*VM^2*N*sigma^3*10/(3*(T*R)^3*nu^2)
+B0 = 1;
+s(1) = sqrt(-A/log(B0/10^25));
+//For B0;
+s = s(1):0.0001:0.029;
+B0 = exp(57.565)*exp(-A./s.^2);
+plot(s,B0)
+title('B0 vs s')
+xlabel('s')
+ylabel('B0')
diff --git a/839/CH27/EX27.4/Example_27_4.sce b/839/CH27/EX27.4/Example_27_4.sce
new file mode 100755
index 000000000..bd01d481b
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+++ b/839/CH27/EX27.4/Example_27_4.sce
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+//clear//
+clear;
+clc;
+
+//Example 27.4
+//Given
+alpha = 1+0.029;
+//From Example 27.3
+sigma = 2.5; //[erg/cm^3]
+T = 300; //[K]
+N = 6.0222*10^23;
+R = 8.3134*10^7; //[erg/g mol-K]
+M = 74.56; //[Molecular weight]
+rho = 1.988; //[g/cm^3]
+nu = 2;
+VM = M/rho; //[cm^3/g mol]
+
+//Using Eq.(27.9)
+L = 4*VM*sigma/(2*R*T*log(alpha))*10^7; //[nm]
+disp('nm',L,'size of nuclues (L) = ');
diff --git a/839/CH27/EX27.5/Example_27_5.sce b/839/CH27/EX27.5/Example_27_5.sce
new file mode 100755
index 000000000..07942177e
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+++ b/839/CH27/EX27.5/Example_27_5.sce
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+//clear//
+clear;
+clc;
+
+//Example 27.5
+//Let: A = MgSO4; B = MgSO4.7H2O; C = H2O
+//Given
+xA = 0.31;
+T = 86; //[F]
+Tb = 2; //[F]
+vbys = 0.15;
+//PB = 
+rho_cr = 105; //[lb/ft^3]
+rho_ml = 82.5; //[lb/ft^3]
+
+//Solution
+//Basis:
+F = 10000; //[lb/h]
+//From Fig 27.13 and Fig 27.4
+crbyml = vbys*rho_cr/((1-vbys)*rho_ml);
+ml_prod = F/crbyml; //[lb/h]
+magma_prod = F+ml_prod //[lb/h]
+xA_avg = (crbyml*0.488+0.285)/1.224;
+//The enthalpy of the magam
+Hmag = (crbyml*(-149)+(-43))/1.224; //[Btu/lb]
+//These are the concenrations of the point e. The point for the feed must 
+//lie on the straight line ae. 
+//The enthalpy of the feed
+Hf = -21; //[Btu/lb]
+//Temperature of the feed
+Tf = 130; //[F]
+//By COG principle, the evaporation rate
+evap_rate = magma_prod*(Hf-Hmag)/(1098-Hf); //[lb/h]
+Total_feed = magma_prod+evap_rate; //[lb/h]
+disp('F',Tf,'Temperature of the feed is');
+disp('lb/h',Total_feed,'Total feed rate');
+disp('lb/h',evap_rate,'Total evaporation rate');
diff --git a/839/CH27/EX27.6/Example_27_6.sce b/839/CH27/EX27.6/Example_27_6.sce
new file mode 100755
index 000000000..9af6b91e6
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+++ b/839/CH27/EX27.6/Example_27_6.sce
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+//clear//
+clear;
+clc;
+
+//Example 27.6
+//Given
+G = 0.0018; //[ft/h]
+//Solution
+//Screen opening of 20-mesh standard screen is,
+L = 0.00273; //[ft], Appendix 20
+a = 1; //[Eq.27.16]
+//From Example 27.5
+//The volume flow rate of mother liquor in the product magma
+Q = 44520/82.5; //[ft^3/h]
+//Since, when z=3,
+Lpr = L; //[ft]
+//Using Eq.(27.28)
+//drawdown time
+tou = Lpr/(3*G); //[h]
+//volume of the liquid in the crystallizer
+Vc = tou*Q; //[ft^3]
+//Total magma volume
+Vmagma = Vc/0.85*7.47; //[gal]
+disp('gal',Vmagma,'The magma volume in the crystallizer be');
+//Using Eq.(27.44)
+//The nucleation rate is
+C = 10000; //[lb/h]
+rho_c = 105;
+B0 = 9*C/(2*rho_c*Vc*Lpr^3); //[nuclei/ft^3-h]
+disp('nuclei/ft^3-h',B0,'The nucleation rate necessary is');
+//Using Eq.(27.40), the zero-size particle density is
+n0 = B0/0.0018; //[nuclei/ft^4]
+L1 = (0:8)*10^-3;
+//Using Eq.(27.27)
+//Let A = log10(n), B = log10(n0)
+B = log10(n0);
+A = B - 1.1*10^3*L1/(2.3026);
+figure(1);
+plot(L1*10^3,A);
+xgrid();
+xlabel('L x 10^3 ft');
+ylabel('log n');
+title('Population density vs length');
+
+//From Fig. 27.15c for values of z corresponding to mesh openings.
+L1 = [11,14,16,19,23,27,33,38,46,54,65,78]'*10^-2;
+z = L1/(tou*G*100); //[mm]
+t = 0;
+function f = fun(z,xm)
+  f = z^3*exp(-z)/6;
+endfunction
+[xm]=ode(0,0,z,fun);
+for i=1:length(xm)
+   Diff(i) = z(i)^3*exp(-z(i))/6;
+end 
+figure(2);
+subplot(2,1,1);
+plot(z,xm);
+xgrid();
+xlabel('z');
+ylabel('xm');
+title('cumulative mass distribution');
+subplot(2,1,2);
+plot(z,Diff)
+xgrid();
+xlabel('z');
+ylabel('dxm/dz');
+title('differential mass distribution');