From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001 From: priyanka Date: Wed, 24 Jun 2015 15:03:17 +0530 Subject: initial commit / add all books --- 905/CH4/EX4.5/4_5.sce | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) create mode 100755 905/CH4/EX4.5/4_5.sce (limited to '905/CH4/EX4.5') diff --git a/905/CH4/EX4.5/4_5.sce b/905/CH4/EX4.5/4_5.sce new file mode 100755 index 000000000..3e350f401 --- /dev/null +++ b/905/CH4/EX4.5/4_5.sce @@ -0,0 +1,120 @@ +clear; +clc; + +// Illustration 4.5 +// Page: 245 + +printf('Illustration 4.5 - Page: 245\n\n'); + +// solution +//*****Data*****// +// a-chloroform b-water c-air +T = 298; // [K] +Dv = 1; // [vessel diameter, m] +Vb = 10; // [kg/s] +ca = 240*10^-6; // [gram/l] +xr = 0.9; // [chloroform which is to be removed] +m = 220; +Ds = 0.5; // [diameter of sparger, m] +no = 90; // [number of orifices] +Do = 3*10^-3; // [diameter of orifice, m] +nm = 0.6; // [mechanical efficiency] +rowb = 1000; // [kg/cubic m] +R = 8.314; +Mc = 29; // [gram/mole] +Mb = 18; // [gram/mole] +g = 9.8; // [square m/s] +//*****// + +Vair = 0.1; // [kg/s as calculated in chapter 3] +mg = Vair/no; // [mass flow rate through each orifice, kg/s] +ug = 1.8*10^-5; // [kg/m.s] +Reo = 25940; // [Renoylds number] +// From equ. 4.20 +dp = 0.0071*Reo^-0.05; // [m] + +// Since the water column height is not known, therefore an iterative procedure must be implemented. +// Assuming column height, Z = 0.5 m +Z = 0.5; // [m] +// For Z = 0.5 m +rowl = 1000; // [kg/cubic m] +Ps = 101.3; // [kPa] +Po = Ps + (1000*9.8*0.5/1000); // [kPa] +Pavg = (Po+Ps)/2; // [kPa] +rowg = Pavg*Mc/(R*T); // [kg/cubic m] + +area = %pi*Dv^2/4; // [square m] +vg = Vair/(rowg*area); // [m/s] +// In this case rowl = rowg and sigma = sigmaAW +// From equation 4.22 +// Vg = vg +// vg/vs = 0.182 +vs = vg/0.182; // [m/s] +vl = -Vb/(rowl*area); // [negative because water flows downward, m/s] +// From equ 4.21 + +deff('[y] = f12(phig)','y = vs - (vg/phig)-(-vl/(1-phig))'); +phig = fsolve(0.1,f12); +// Now in this case +S = vl/(1-phig); +// Value of 'S' comes out to be less than 0.15 m/s +// Therefore +dp = (dp^3*Po/Pavg)^(1/3); // [m] +// From equ 4.23 +a = 6*phig/dp; // [m^-1] +// Now we calculate diffusivity of chloroform +Vba = 88.6; // [cubic cm/mole] +u = 0.9*10^-3; // [Pa-s] +e = (9.58/(Vba)-1.12); +// From equation 1.53 +Dl = 1.25*10^-8*((Vba)^-0.19 - 0.292)*T^1.52*(u*10^3)^e; // [square cm/s] + +// And Schmidt number is +Scl = 833; // [Schmidt Number] + +// Now we calculate dp*g^(1/3)/Dl^(2/3) = J +J = dp*g^(1/3)/(Dl*10^-4)^(2/3) +Reg = dp*vs*rowl/u; // [Gas bubble Renoylds number] +// From equ 4.25 +Shl = 2 + 0.0187*Reg^0.779*Scl^0.546*J^0.116; + +// For dilute solution xbm = 1 or c = 55.5 kmole/cubic m +// Then for Nb = 0 +c = 55.5; // [kmole/cubic m] +kx = Shl*c*Dl*10^-4/dp; // [kmole/square m.s] +mtc = kx*a; // [kmole/cubic m.s] + +L = Vb/Mb; // [kmole/s] +Gmx = L/area; // [kmole/square m.s] +V = Vair/Mc; // [kmole/s] +A = L/(m*V); // [absorption factor] + +// From equ 4.28 + // For, xin/xout = x = 10 + x = 10; +Z = (Gmx/(kx*a*(1-A)))*log(x*(1-A)+A); + +// With this new estimated Z ,we again calculate average pressure in the // column of water +Po1 = 110.1; // [kPa] +Pavg1 = 105.7; // [kPa] +rowg1 = Pavg1*Mc/(R*T); +// Now value of rowg1 obtained is very close to value used in the first // iteration. Therefore on three iteractions we achieve a value of 'Z' +Z1 = 0.904; // [m] + +rowgo = Po1*Mc/(R*T); // [kg/cubic m] +vo1 = 4*mg/(%pi*Do^2*rowgo); // [m/s] +// Therefore, vo1^2/(2*gc) = F +gc = 1; +F = vo1^2/(2*gc); // [J/kg] +// And R*T*log(Po/Ps)/Mc = G +G = R*T*1000*log(Po1/Ps)/Mc; // [J/kg] +Zs = 0 +// And (Z1-Zs)*g/gc = H +H = (Z1-Zs)*g/gc; // [J/kg] +// From equ 4.27 +W = F+G+H; // [J/kg] +// Now the air compressor power is +W1 = W*Vair*10^-3/nm; // [kW] + +printf("The depth of the water column required to achieve the specified 90percent removal efficiency is %f m\n\n",Z1); +printf("The power required to operate the air compressor is %f kW\n\n",W1); \ No newline at end of file -- cgit