clear; clc; // Illustration 13.2 // Page: 749 printf('Illustration 13.2 - Page: 749\n\n'); // Solution //***Data***// // Eqb=[x(Wt fraction NaOH in clear solution) N(kg CaCO3/kg soln in settled sludge) y*(wt fraction NaOH in soln of settled sludge)] // a=H2O b=CaCO3 c=NaOH Eqb = [0.090 0.495 0.0917;0.0700 0.525 0.0762;0.0473 0.568 0.0608;0.0330 0.600 0.0452;0.0208 0.620 0.0295;0.01187 0.650 0.0204;0.00710 0.659 0.01435;0.00450 0.666 0.01015]; deff('[y]=f80(x)','y=0'); x = 0:0.01:0.12; Mass_c = 0.1;// [kg] Mass_b = 0.125;// [kg] Mass_a = 0.9;// [kg] //**************// scf(42); plot(x,f80,Eqb(:,3),Eqb(:,2)); xgrid(); xlabel("x,y Wt. fraction of NaOH in loquid"); ylabel("N kg CaCO3 / kg solution"); legend("N Vs x","N Vs Y"); title("Equilibrium Plot") // Basis: 1 kg soln in original mixture. // As in Fig. 13.27 (Pg 750) // The original mixture corresponds to M1: NM1 = 0.125;// [kg CaCO3/kg soln] yM1 = 0.1;// [kg NaOH/kg solution] // The tie line through M1 is drawn. At point E1 representing the settled sludge: N1 = 0.47;// [kg CaCO3/kg soln] y1 = 0.100;// [kg NaOH/kg solution] E1 = Mass_b/N1;// [kg soln. in sludge] Ro = 1-E1;// [kg clear soln drawn] // Stage 2: xo = 0;// [kg NaOH/kg soln] // By Eqn. 13.11: M2 = E1+Ro;// [kg liquid] // By Eqn. 13.12: NM2 = Mass_b/(E1+Ro);// [kg CaCO3/kg soln] // M2 is located on line RoE1. At this value of N, and the tie line through M2 is drawn. At E2: N2 = 0.62;// [kg CaCO3/kg soln] y2 = 0.035;// [kg NaOH/kg solution] E2 = Mass_b/N2;// [kg soln. in sludge] Ro = 1-E2;// [kg clear soln drawn] // Stage 3: xo = 0;// [kg NaOH/kg soln] // By Eqn. 13.11: M3 = E2+Ro;// [kg liquid] // By Eqn. 13.12: NM3 = Mass_b/M3;// [kg CaCO3/kg soln] // Tie line E3R3 is located through M3.At E3: N3 = 0.662;// [kg CaCO3/kg soln] y3 = 0.012;// [kg NaOH/kg solution] // By Eqn. 13.8: E3 = Mass_b/N3;// [kg soln. in sludge] printf("The fraction of original NaOH in the slurry: %f \n",E3*y3/Mass_c);