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diff --git a/Chemical_Reactor_Design_by_P_Harriott/7-Gas_Liquid_Reactions.ipynb b/Chemical_Reactor_Design_by_P_Harriott/7-Gas_Liquid_Reactions.ipynb new file mode 100644 index 0000000..fc0df3c --- /dev/null +++ b/Chemical_Reactor_Design_by_P_Harriott/7-Gas_Liquid_Reactions.ipynb @@ -0,0 +1,748 @@ +{ +"cells": [ + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Chapter 7: Gas Liquid Reactions" + ] + }, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 7.1: EX7_1.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"//Harriot P.,2003,Chemical Reactor Design (I-Edition) Marcel Dekker,Inc.,USA,pp 436.\n", +"//Chapter-7 Ex7.1 Pg No.260\n", +"//Title:Overall Reaction Rate Coefficient, Percent Resistance, Reaction Volume and Reactor Size\n", +"//===========================================================================================================\n", +"clear\n", +"clc\n", +"// COMMON INPUT\n", +"k2=8.5;//Reaction rate constant (L/mol-sec)\n", +"T=50;//Reaction condition temperature(°C)\n", +"P=2;//Reaction Pressure (atm)\n", +"H_O2=8*10^4;// Solubility (atm/mol fraction)\n", +"F=17000//Feed rate (L/hr)\n", +"C_B_feed=1.6;//Feed concentration(M)\n", +"C_B_product=0.8;//Product concentration(M)\n", +"k_L_a=900;//Liquid film mass transfer coefficient(hr-1)\n", +"k_g_a=80;//Gas film mass transfer coefficient(mol/hr L atm)\n", +"Epsilon=0.1;//Porosity\n", +"percent_inc=0.2;//Percentage excess required for reactor volume\n", +"\n", +"\n", +"//CALCULATION (Ex7.1.a)\n", +"H_O2_conv=H_O2*18/1000;// Convert (atm L/mole O2)\n", +"k_L_a_by_H=k_L_a/H_O2_conv;\n", +"reaction_resistance=H_O2_conv/(k2*C_B_product*(1-Epsilon)*3600);\n", +"Kg_a=1/((1/k_g_a)+(1/k_L_a_by_H)+(reaction_resistance));//Refer equation7.10\n", +"gasfilm_resistance_per=((1/k_g_a)/(1/Kg_a))*100;\n", +"liq_film_resistance_per=((1/k_L_a_by_H)/(1/Kg_a))*100;\n", +"reaction_resistance_per=((reaction_resistance)/(1/Kg_a))*100;\n", +"\n", +"//CALCULATION (Ex7.1.b)\n", +"delta_C_B=C_B_feed-C_B_product;\n", +"mol_O2_needed=F*delta_C_B/4;\n", +"N_air=100;//Assuming 100 mole of feed air\n", +"f_O2=0.209;//Fraction of O2\n", +"f_N2=1-f_O2;//Fraction of N2\n", +"N_O2_in=N_air*f_O2;\n", +"N_N2_in=N_air*f_N2;\n", +"N_O2_out=N_O2_in/2;//Half of O2 fed\n", +"N_N2_out=N_N2_in;\n", +"N_air_out=N_N2_out+N_O2_out;\n", +"P_O2_out=P*(N_O2_out/N_air_out);\n", +"P_O2_in=P*(N_O2_in/N_air);\n", +"P_O2_bar=(P_O2_in-P_O2_out)/(log(P_O2_in/P_O2_out));//Log mean Pressure\n", +"volume=mol_O2_needed/(Kg_a*P_O2_bar);\n", +"reactor_vol=volume+volume*percent_inc;\n", +"volume_gal=volume*0.264;\n", +"reactor_vol_gal=reactor_vol*0.264;\n", +"\n", +"\n", +"//OUTPUT (Ex7.1.a)\n", +"mprintf('\n OUTPUT Ex7.1.a');\n", +"mprintf('\n==========================================================');\n", +"mprintf('\nThe percentage gas-film resistance : %0.1f%%',gasfilm_resistance_per);\n", +"mprintf('\nThe percentage liquid-film resistance: %0.1f%%',liq_film_resistance_per);\n", +"mprintf('\nThe percentage chemical reaction resistance: %0.1f%%',reaction_resistance_per);\n", +"\n", +"//OUTPUT (Ex7.1.b)\n", +"mprintf('\n\n\n OUTPUT Ex7.1.b');\n", +"mprintf('\n==========================================================');\n", +"mprintf('\n Reaction volume calculated : %0.0f L ',volume );\n", +"mprintf('\n Reactor size to be chosen : %0.0f L',reactor_vol);\n", +"\n", +"\n", +"// FILE OUTPUT\n", +"fid= mopen('.\Chapter7-Ex1-Output.txt','w');\n", +"mfprintf(fid,'\n OUTPUT Ex7.1.a');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\nThe percentage gas-film resistance : %0.1f%%',gasfilm_resistance_per);\n", +"mfprintf(fid,'\nThe percentage liquid-film resistance: %0.1f%%',liq_film_resistance_per);\n", +"mfprintf(fid,'\nThe percentage chemical reaction resistance: %0.1f%%',reaction_resistance_per);\n", +"mfprintf(fid,'\n\n\n OUTPUT Ex7.1.b');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\n Reaction volume calculated : %0.0f L ',volume );\n", +"mfprintf(fid,'\n Reactor size to be chosen : %0.0f L',reactor_vol);\n", +"mclose(fid);\n", +"//===================================================END OF PROGRAM======================================================\n", +"\n", +"" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 7.2: The_gradient_for_B_in_the_liquid_film.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"//Harriot P.,2003,Chemical Reactor Design (I-Edition) Marcel Dekker,Inc. USA,pp 436.\n", +"//Chapter-7 Ex7.2 Pg No.270\n", +"//Title:The gradient for B in the liquid film\n", +"//===========================================================================================================\n", +"clear\n", +"clc\n", +"//INPUT\n", +"C_B0_by_C_Ai=40;\n", +"D_A_by_D_B=1.2;\n", +"sqrt_M=10;\n", +"phi=sqrt_M;//Assume the gradient for A is the same as when the gradient for B is negligible\n", +"eff_diff_distA_by_xL=(1/phi);\n", +"\n", +"//CALCULATION\n", +"eff_diff_distB_by_xL=(1-eff_diff_distA_by_xL);\n", +"CB0_minus_CBbar_by_CB0=D_A_by_D_B*(1/C_B0_by_C_Ai)*(eff_diff_distB_by_xL/eff_diff_distA_by_xL);\n", +"C_Bbar_by_C_B0=(1-CB0_minus_CBbar_by_CB0);\n", +"sqrt_kC_B=sqrt(C_Bbar_by_C_B0);\n", +"phi_corrected=phi*sqrt_kC_B;\n", +"Percent_change=((phi-phi_corrected)/(phi))*100;\n", +"\n", +"//OUTPUT\n", +"mprintf('\n Percentage Decrease in Rate :%0.0f%% ',Percent_change);\n", +"mprintf('\n The decrease in rate is significant ,hence the gradient for B is significant in liquid film');\n", +"fid= mopen('.\Chapter7-Ex2-Output.txt','w');\n", +"mfprintf(fid,'\n Percentage Decrease in Rate :%0.0f%% ',Percent_change);\n", +"mfprintf(fid,'\n The decrease in rate is significant ,hence the gradient for B is significant in liquid film');\n", +"mclose(fid);\n", +"//================================================END OF PROGRAM==========================================================" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 7.3: Overall_mass_transfer_coefficient_and_percent_resistance.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"//Harriot P.,2003,Chemical Reactor Design (I-Edition) Marcel Dekker,Inc.,USA,pp 436\n", +"//Chapter-7 Ex7.3 Pg No.274\n", +"//Title:Overall mass transfer coefficient and percent resistance \n", +"//===========================================================================================================\n", +"clear\n", +"clc\n", +"//INPUT\n", +"k2=8500;//(L/mol sec) at 25 °C\n", +"kg_a= 7.4 //(mol/hr ft3 atm)\n", +"k_star_L_a=32;//(hr-1)\n", +"a=34;//(ft2/ft3)\n", +"H_CO2=1.9*10^(3);//(atm/m f) Henry's Constant\n", +"D_CO2=2*10^(-5);//(cm2/sec)\n", +"D_OH=2.8*10^(-5);//(cm2/sec)\n", +"P_CO2_in=0.04;//(atm)\n", +"P_CO2_out=0.004;//(atm)\n", +"Caustic_conc=[0.5 0.75];//Cocentration on both the ends of the column bottom and top(M)\n", +"n=2;\n", +"M_H2O=18;//Molecular Weight\n", +"H_H2O=62.3;//(g/ft3) Henry's Constant\n", +"H_H2O_dash=H_H2O/M_H2O;//Henry's Constant converted into consistent units with kg_a\n", +"\n", +"\n", +"//CALCULATION\n", +"C_Ai=P_CO2_in/H_CO2*(1000/18);\n", +"k_star_L=(k_star_L_a/(a*3600))*(30.5);\n", +"H_CO2_dash=H_CO2*(1/H_H2O_dash);\n", +"for i=1:2\n", +"Phi_a(i)=(1+(Caustic_conc(i)/(n*C_Ai))*(D_OH/D_CO2));//Refer equation7.51\n", +"sqrt_M(i)=sqrt(k2*Caustic_conc(i)*D_CO2)/k_star_L;\n", +"Phi(i)=sqrt_M(i);//Refer fig 7.7\n", +"K_ga(i)=(1/((1/kg_a)+(H_CO2_dash/(Phi(i)*k_star_L_a))));//Overall Mass transfer coefficient\n", +"Percent_resis_gasfilm(i)=(K_ga(i)/kg_a)*100;\n", +"end\n", +"\n", +"//OUTPUT\n", +"mprintf('\n \t\t\t\t\t\t\tTop\t Bottom');\n", +"mprintf('\n Overall mass transfer coefficient (mol/hr ft3 atm): %0.1f\t %0.1f',K_ga(1),K_ga(2));\n", +"mprintf('\n Percenage resistance in gas film: %0.0f%%\t %0.0f%% ',Percent_resis_gasfilm(1) ,Percent_resis_gasfilm(2) );\n", +"\n", +"//FILE OUTPUT\n", +"fid= mopen('.\Chapter7-Ex3-Output.txt','w');\n", +"mfprintf(fid,'\n \t\t\t\t\t\t\tTop\t Bottom');\n", +"mfprintf(fid,'\n Overall mass transfer coefficient (mol/hr ft3 atm): %0.1f\t %0.1f',K_ga(1),K_ga(2));\n", +"mfprintf(fid,'\n Percenage resistance in gas film: %0.0f%%\t %0.0f%% ',Percent_resis_gasfilm(1) ,Percent_resis_gasfilm(2) );\n", +"mclose(fid);\n", +"//========================================================================END OF PROGRAM=================================================================================\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 7.4: Local_selectivity_due_to_mass_transfer_limitations.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"//Harriot P.,2003,Chemical Reactor Design (I-Edition) Marcel Dekker,Inc.,USA,pp 436\n", +"//Chapter-7 Ex7.4 Pg No.279\n", +"//Title:Local selectivity due to mass transfer limitations\n", +"//===========================================================================================================\n", +"clear\n", +"clc\n", +"//INPUT\n", +"C_Ai=0.02;//(M)\n", +"C_B0=3;//(M)\n", +"D_A=10^(-5);//(cm2/sec)\n", +"D_B=D_A;//(cm2/sec)\n", +"D_C=D_B;//(cm2/sec)\n", +"k_1=10^(4);//(L/mol sec)\n", +"k_star_l=0.015;//(cm/sec)\n", +"n=1;\n", +"C_c0=[0 1.4];\n", +"X=[0 0.5]// Conversion\n", +"Phi=[33 23];//From figure 7.7\n", +"\n", +"\n", +"//CALCULATION\n", +"k_2=0.09*k_1;\n", +"for i=1:2\n", +" C_B(i)=(1-X(i))*C_B0;\n", +"sqrt_M(i)=sqrt(C_B(i)*k_1*D_A)/k_star_l;\n", +"Phi_a(i)=(1+(C_B(i)/(n*C_Ai))*(D_B/D_A));//Refer equation 7.51\n", +"C_Bbar_by_C_B(i)=(Phi(i)/sqrt_M(i))^2;//Refer equation 7.59\n", +"delta_C_B(i)=(1-C_Bbar_by_C_B(i))*C_B(i);//Refer equation 7.60\n", +"delta_C_c(i)=delta_C_B(i);\n", +"C_cbar(i)=delta_C_c(i)+C_c0(i);\n", +"C_Bbar(i)=C_Bbar_by_C_B(i)*(C_B(i));\n", +"S(i)=(1-(k_2*C_cbar(i)/(C_Bbar(i)*k_1)))*100;//Refer equation 7.56\n", +"end\n", +"\n", +"//OUTPUT\n", +"mprintf('\n\tLocal selectivity due to mass transfer limitations ');\n", +"mprintf('\n\tThe local selectivity for Zero Conversion : %0.0f%%',S(1));\n", +"mprintf('\n\tThe local selectivity for 50%% Conversion : %0.0f%%',S(2));\n", +"\n", +"//FILE OUTPUT\n", +"fid= mopen('.\Chapter7-Ex4-Output.txt','w');\n", +"mfprintf(fid,'\n\tLocal selectivity due to mass transfer limitations ');\n", +"mfprintf(fid,'\n\tThe local selectivity for Zero Conversion is %0.0f%%',S(1));\n", +"mfprintf(fid,'\n\tThe local selectivity for 50%% Conversion is %0.0f%%',S(2));\n", +"mclose(fid);\n", +"//======================================================END OF PROGRAM===================================================\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 7.5: Maximum_rate_of_CO_absorption_and_Dimensions_of_Bubble_Column_Reactor.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"//Harriot P.,2003,Chemical Reactor Design (I-Edition) Marcel Dekker,Inc.,USA,pp 436\n", +"//Chapter-7 Ex7.5 Pg No.293\n", +"//Title:Maximum rate of CO absorption and Dimensions of Bubble Column Reactor\n", +"//===========================================================================================================\n", +"clear\n", +"clc\n", +"// COMMON INPUT\n", +"P_dash=5;//Partial pressure of acetic acid (atm)\n", +"P_total=20;//Total Pressure (atm)\n", +"myu=0.19;// Viscosity of acetic acid\n", +"T_C=180;//Temperature in (°C)\n", +"T_K=T_C+273;//Temperature in (K)\n", +"sigma_20=28;//Surface Tension(Dynes/cm) at 20 (°C)\n", +"sigma_180=20;//Surface Tension (Dynes/cm)at 180 (°C)\n", +"M_CO=28;//Molecular weight of CO\n", +"M_B=60.05;//Molecular weight acetic acid\n", +"V_A= 30.7;//Molar volume\n", +"S_CO=7*10^(-3);//Solubility of CO (mol/L atm)\n", +"f_CO=0.75;//Fraction of CO in feed\n", +"f_acetic_acid=1-f_CO;//Fraction of Acetic acid\n", +"R=82.056*(10^-3);//(cm3 atm/ K mol)\n", +"rho_air=1.21;//(kg/m3)density of air at 20 (°C)\n", +"sigma_H2O=72;//Surface tension (Dynes/cm)\n", +"myu_H2O=1;//Viscosity of water\n", +"k_L_a_air_water=0.051;//(sec-1)\n", +"D_O2_water=2.4*(10^-5);//(cm2/sec)diffusivity for oxygen in waterat 20(°C) \n", +"Conc_Rh=4*10^(-3);//Concentration of Rohdium(M)\n", +"Conc_CH3I=1;//Concentration of Methyl Iodide(M)\n", +"F_product_acetic_acid=0.1;// Rate of acetic acid produced (kmol/sec)\n", +"f_CO_reacted=0.8;//80% of CO reacted\n", +"u_g=0.1;//(m/sec)\n", +"Epsilon_air_water_new=0.07;//At velocity 3(cm/sec)\n", +"Epsilon_air_water_old= 0.12;//At velocity 6(cm/sec)\n", +"u_g_c=5*(10^(-2));//Gas Velocity Ex7.5.c(m/sec)\n", +"\n", +"\n", +"\n", +"//CALCUATION (Ex7.5.a)\n", +"D_CO=(7.4*10^(-8)*M_B^(1/2)*T_K)/(myu*V_A^(0.6));//Diffusivity of CO (Wilke–Chang equation Eq4.17)\n", +"M_ave=f_CO*M_CO+M_B*f_acetic_acid;//Average Molecular weight\n", +"rho_g=M_ave*P_total/(R*T_K);//From ideal gas law\n", +"epsilon_air_water= 0.12;//At velocity 6(cm/sec)\n", +"epsilon=epsilon_air_water*(sigma_H2O/sigma_180)^(0.4)*(myu/myu_H2O)^(0.2)*(rho_g/rho_air)^(0.2);//From equation 7.64\n", +"u_G=6;//From figure 7.12(cm/sec)\n", +"k_L_a=k_L_a_air_water*(D_CO/D_O2_water)^(0.5)*(epsilon/epsilon_air_water);//From equation 7.69\n", +"P_CO=P_total-P_dash;\n", +"C_CO_Star=S_CO*P_CO;\n", +"r_max=C_CO_Star*k_L_a;//Rate of CO absorption at 15 atm\n", +"r_test=158.8*(10^(6))*exp(-8684/T_K)*(Conc_Rh)*(Conc_CH3I);//Kinetic rate at 180 (°C) \n", +"\n", +"//CALCULATION(Ex7.5.b)\n", +"F_feed_CO=F_product_acetic_acid/f_CO_reacted;//Rate of flow of CO (kmol/sec)\n", +"F_total=F_feed_CO/f_CO;\n", +"Q=F_total*R*T_K/(P_total);\n", +"S=Q/u_g;\n", +"D_t=sqrt(4*S/%pi);\n", +"r_test_b=(158.8*(10^(6))*exp(-8684/T_K)*(Conc_Rh)*(Conc_CH3I))*(10^(-3));//Kinetic rate at 180 (°C) \n", +"liquid_vol= (F_product_acetic_acid/r_test_b)*(10^(-3));//liquid volume (m3)\n", +"h0=liquid_vol/S;//clear liquid\n", +"h=h0/(1-epsilon);//aerated liquid\n", +"\n", +"//CALCULATION(Ex7.5.c)\n", +"Q=F_total*R*T_K/(P_total);\n", +"S=Q/u_g_c;\n", +"D_t_c=sqrt(4*S/%pi);\n", +"Epsilon_new=(Epsilon_air_water_new/Epsilon_air_water_old)*epsilon;\n", +"liquid_vol= (F_product_acetic_acid/r_test_b)*(10^(-3));//liquid volume (m3)\n", +"h0=liquid_vol/S;//clear liquid\n", +"h_new=h0/(1-Epsilon_new);//aerated liquid\n", +"\n", +"//OUTPUT (Ex7.5.a)\n", +"mprintf('\n OUTPUT Ex7.5.a');\n", +"mprintf('\n==========================================================');\n", +"mprintf('\n\tThe maximum rate of CO absorption at 15 atm : %f (mol/L s)',r_max);\n", +"mprintf('\n\tThe kinetic rate of CO absorption at 180(°C) : %f (mol/L s)',r_test);\n", +"mprintf('\n\tThe predicted value of k_L_a : %0.2f (s-1)',k_L_a);\n", +"\n", +"//OUTPUT (Ex7.5.b)\n", +"mprintf('\n\n\n OUTPUT Ex7.5.b');\n", +"mprintf('\n==========================================================');\n", +"mprintf('\n\tThe Dimensions of the reactor are ');\n", +"mprintf('\n\tDiameter:%0.0f m',D_t); \n", +"mprintf('\n\tHeight:%0.2f m',h); \n", +"\n", +"//OUTPUT (Ex7.5.c)\n", +"mprintf('\n\n\n OUTPUT Ex7.5.c');\n", +"mprintf('\n==========================================================');\n", +"mprintf('\n\tThe new dimensions of the reactor');\n", +"mprintf('\n\tDiameter:%0.1f m',D_t_c);\n", +"mprintf('\n\tHeight:%0.1f m',h_new);\n", +"\n", +"//FILE OUTPUT\n", +"fid= mopen('.\Chapter7-Ex5-Output.txt','w');\n", +"mfprintf(fid,'\n OUTPUT Ex7.5.a');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\n\tThe maximum rate of CO absorption at 15 atm : %f (mol/L s)',r_max);\n", +"mfprintf(fid,'\n\tThe kinetic rate of CO absorption at 180(°C) : %f (mol/L s)',r_test);\n", +"mfprintf(fid,'\n\tThe predicted value of k_L_a : %0.2f (s-1)',k_L_a);\n", +"mfprintf(fid,'\n\n\n OUTPUT Ex7.5.b');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\n\tThe Dimensions of the reactor are ');\n", +"mfprintf(fid,'\n\tDiameter:%0.0f m',D_t); \n", +"mfprintf(fid,'\n\tHeight:%0.2f m',h); \n", +"mfprintf(fid,'\n\n\n OUTPUT Ex7.5.c');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\n\tThe new dimensions of the reactor');\n", +"mfprintf(fid,'\n\tDiameter:%0.1f m',D_t_c);\n", +"mfprintf(fid,'\n\tHeight:%0.1f m',h_new);\n", +"mclose(fid);\n", +"\n", +"//=================================================END OF PROGRAM===========================================================\n", +"\n", +"\n", +"" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 7.6: Fraction_of_O2_Power_of_agitator_kLa_and_average_dissolved_oxygen_concentration.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"//Harriot P,2003,Chemical Reactor Design (I-Edition) Marcel Dekker,Inc., USA,pp 436.\n", +"//Chapter-7 Ex7.6 Pg No.300\n", +"//Title:Fraction of O2,Power of agitator, k_L_a and average dissolved oxygen concentration.\n", +"//======================================================================================================================\n", +"clear\n", +"clc\n", +"// COMMON INPUT\n", +"Vol_reactor=200;//Volume of reactor (m3)\n", +"D=4;//Diameter of reactor (m)\n", +"depth=12;//Depth of reactor (m) \n", +"u_g=3;//Superficial velocity (cm/sec)\n", +"T_C=30;//Temperature (°C)\n", +"T_K=273+T_C;//Temperature (K)\n", +"f_O2=0.21;//Fraction of O2 in air\n", +"myu_soln=1.5*(10^(-3));//Viscosity of solution (Pa sec)\n", +"R=0.08206;//Gas constant (m3 atm/ K kmol)\n", +"r_O2_peak=45*(10^(-3));//Flow rate of O2 at peak demand \n", +"Da_by_Dt=(1/3);\n", +"Da=1.333;//(m)\n", +"N=120;//(rpm)\n", +"N_conv=(N/60);//(sec-1)\n", +"Press_top=1;//Pressure at the top of the vessel (atm) \n", +"rho=1000;//Density of water (kg/m3)\n", +"ug_sup1=3*(10^(-2));//based on 30(°C) and 1 (atm)\n", +"V=151;//Volume of solution calculated Ex7.6.a (m3)\n", +"ug_sup1=3*(10^(-2));//based on 30(°C) and 1 atm.\n", +"Press_top=1;//Pressure at the top of the vessel (atm) \n", +"Press_bottom=2;//From Ex7.6.c\n", +"ug_sup2=ug_sup1/Press_bottom;// at 2atm superficial velocity (cm/sec)\n", +"ug_ave=(ug_sup1+ug_sup2)/2;//Average superficial velocity (cm/sec)\n", +"depth=12;//Depth of reactor (m) \n", +"one_atm_water=10.3;//1 atm pressure corresponds to 10.3 (m) height of water\n", +"k_H_O2=5.2*10^(4)// Henery's law constant for O2 in water for O2 (atm/mol fraction) \n", +"M_O2=32;//Molecular weight of O2\n", +"M_H2O=18;//Molecular weight of water\n", +"C_O2_critical=1*10^(-3);//Critical O2 Concentration (g/L)\n", +"percent_reduction=40/100;//Mass transfer coefficient in the upper region of the reactor is 40% less than the average\n", +"kLa_soln=0.22;//Value calculated in Ex7.6.d \n", +"r_conv=1.25*10^(-5);//Rate at peak O2 demand (mol/L sec)\n", +"depth=12;//Depth of reactor (m) \n", +"\n", +"\n", +"//CALCULATION (Ex7.6.a )\n", +"S=%pi*(D^2)/4;//Cross section area (m2)\n", +"V=S*depth;//Volume of solution(m3)\n", +"F_air=(S*u_g*(10^(-2))*3600)/(R*(10^(-3))*T_K);\n", +"F_O2=f_O2*F_air;//Feed rate of O2 (mol/hr)\n", +"F_O2_used=r_O2_peak*V*(10^(3));//O2 used for aerobic fermentation (mol/hr)\n", +"F_O2_left=F_O2-F_O2_used;//O2 left after aerobic fermentation(mol/hr)\n", +"f_O2_exitgas=F_O2_left/F_air;//Fraction of O2 in exit gas\n", +"Percent_O2_exitgas=(f_O2_exitgas)*(100);\n", +"Frac_O2_used=((f_O2-f_O2_exitgas)/f_O2);\n", +"\n", +"//CALCULATION (Ex7.6.b )\n", +"Re=(rho*N_conv*Da^2)/myu_soln;\n", +"N_p=6;//For a standard turbine \n", +"N_p_pitched=1.7;//For a pitched-blade turbine\n", +"P0=(N_p*rho*(N_conv^3)*(Da^5))*(10^(-3));//Refer equation 7.73 (kW)\n", +"//If the turbine is 2 m from the bottom, or 10 m below the surface,the pressure is about 2 atm since 1atm= 10.3 m water\n", +"Press_bottom=2\n", +"ug_sup2=ug_sup1/Press_bottom;\n", +"Q=ug_sup2*S;\n", +"N_Ae=Q/(N_conv*(Da^3));\n", +"Pg_by_P0=0.55;//From figure 7.15 based on N_Ae value calculated\n", +"Pg=Pg_by_P0*P0;//When aerated\n", +"P0_pitched=(N_p_pitched/N_p)*P0;\n", +"Pg_by_P0_pitched=0.8;//Solution reaching the upper stirrers is already aerated\n", +"Pg_pitched=Pg_by_P0_pitched*P0_pitched;\n", +"Tot_Pow_no_air=P0+Press_bottom*P0_pitched;//Total power when no air is presented\n", +"Tot_Pow_aerated=Pg+Press_bottom*Pg_pitched;//Total power when it is aerated\n", +"\n", +"//CALCULATION (Ex7.6.c )\n", +"P_by_V_ave=Tot_Pow_aerated/V;\n", +"kLa_O2_sulfite=0.32;//Using figure7.16 based on ave(P/V) value and ug_average value\n", +"kLa_soln=0.7*kLa_O2_sulfite;//kLa for this solution is 70% of the value for oxygen absorption in sodium sulfite (sec-1)\n", +"y_O2=0.086;//If gas is backmixed\n", +"depth_ave=depth/2;\n", +"Press_ave=(Press_top+(depth_ave/one_atm_water));//Pressure at average depth (atm)\n", +"C_O2_star=(Press_ave*y_O2/k_H_O2)*(1000/M_H2O);//Conversion (mol/L)\n", +"r_conv=r_O2_peak/3600;//Rate at peak O2 demand (mol/L sec)\n", +"C_ave=(C_O2_star-(r_conv/kLa_soln))\n", +"C_ave_conv=C_ave*M_O2*1000;//Converted value of O2 concentration in(mg/L)\n", +"\n", +"//CALCULATION (Ex7.6.d)\n", +"depth_ave=depth/2;\n", +"Press_ave=(Press_top+(depth_ave/one_atm_water));//Pressure at average depth (atm)\n", +"kLa_soln_reduced=kLa_soln*(1-percent_reduction);\n", +"C_star_minus_C=r_conv/kLa_soln_reduced;\n", +"C_O2_new=(C_O2_star-(C_star_minus_C));\n", +"C_O2_new_conv=C_O2_new*M_O2*1000;//Converted value of O2 concentration in(mg/L)\n", +"C_O2_star_new=C_O2_star/Press_ave;\n", +"\n", +"//OUTPUT (Ex7.6.a)\n", +"mprintf('\n OUTPUT Ex7.6.a');\n", +"mprintf('\n==========================================================');\n", +"mprintf('\nAt the peak demand, fraction of the oxygen supplied = %.3f ',Frac_O2_used);\n", +"\n", +"//OUTPUT(Ex7.6.b )\n", +"mprintf('\n\n\n OUTPUT Ex7.6.b');\n", +"mprintf('\n==========================================================');\n", +"mprintf('\nThe total power required for the agitator before the air is turned on: %0.0f kW',Tot_Pow_no_air);\n", +"mprintf('\nThe total power required for the agitator after the air is turned on: %0.0f kW',Tot_Pow_aerated);\n", +"\n", +"//OUTPUT (Ex7.6.c )\n", +"mprintf('\n\n\n OUTPUT Ex7.6.c');\n", +"mprintf('\n==========================================================');\n", +"mprintf('\nThe calculated value of kLa (mass transfer coefficient) of solution:%0.2f (sec-1)',kLa_soln);\n", +"mprintf('\nThe calculated value of average dissolved O2 concentration: %0.2f (mg/L)',C_ave_conv);\n", +"\n", +" //OUTPUT (Ex7.6.d)\n", +" mprintf('\n\n\n OUTPUT Ex7.6.d');\n", +"mprintf('\n==========================================================');\n", +" mprintf('\nThe new calculated value of average dissolved O2 concentration %0.2f (mg/L)',C_O2_new_conv);\n", +" if(C_star_minus_C>C_O2_star_new)\n", +" mprintf('\nThe reactor is operated above critical O2 concentration ');\n", +" else\n", +" mprintf('\nThe reactor should be operated at higher air rate otherwise C_O2 would drop to zero')\n", +" end\n", +" // FILE OUTPUT\n", +"fid= mopen('.\Chapter7-Ex6-Output.txt','w');\n", +"mfprintf(fid,'\n OUTPUT Ex7.6.a');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\nAt the peak demand, fraction of the oxygen supplied = %.3f ',Frac_O2_used);\n", +"mfprintf(fid,'\n\n\n OUTPUT Ex7.6.b');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\nThe total power required for the agitator before the air is turned on: %0.0f kW',Tot_Pow_no_air);\n", +"mfprintf(fid,'\nThe total power required for the agitator after the air is turned on: %0.0f kW',Tot_Pow_aerated);\n", +"mfprintf(fid,'\n\n\n OUTPUT Ex7.6.c');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\nThe calculated value of kLa (mass transfer coefficient) of solution:%0.2f (sec-1)',kLa_soln);\n", +"mfprintf(fid,'\nThe calculated value of average dissolved O2 concentration: %0.2f (mg/L)',C_ave_conv);\n", +"mfprintf(fid,'\n\n\n OUTPUT Ex7.6.d');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\nThe new calculated value of average dissolved O2 concentration %0.2f (mg/L)',C_O2_new_conv);\n", +" if(C_star_minus_C>C_O2_star_new)\n", +" mfprintf(fid,'\nThe reactor is operated above critical O2 concentration ');\n", +" else\n", +" mfprintf(fid,'\nThe reactor should be operated at higher air rate otherwise C_O2 would drop to zero')\n", +" end\n", +" mclose(fid);\n", +"//===================================================END OF PROGRAM======================================================\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"\n", +"" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 7.7: EX7_7.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"//Harriot P.,2003,Chemical Reactor Design (I-Edition) Marcel Dekker,Inc.,USA,pp 436.\n", +"//Chapter-7 Ex7.7 Pg No.304\n", +"//Title:Apparent value of kLa, regime of operation and selectivity dependency on gas mixing\n", +"//======================================================================================================================\n", +"clear\n", +"clc\n", +"//INPUT\n", +"Vol_reactor=35;//Volume of reactor(L)\n", +"No_reactor=3;//No. of reactor\n", +"T_C=155;//Operating Temperature (°C)\n", +"T_ref=273;//Reference Temperature (°C)\n", +"T_K= T_C+T_ref;//Operating Temperature (K)\n", +"P=8.2;//Operating Pressure (atm)\n", +"X_conversion=9.5*10^(-2);//Conversion\n", +"S=73*10^(-2);//Selectivity\n", +"M_cyclohexane=84.16;//Molecular weight of cyclohexane\n", +"F_cyclohexane=100;//Feed rate of cyclohexane (L/hr)\n", +"F_air=9.9;//Feed rate of air (nm3/hr)\n", +"f_O2_air=0.21;//Fraction of O2 in air\n", +"V_ref=22400;//Reference volume at STP(cm3/mol)\n", +"y_O2=0.002;//O2 in vent gas\n", +"f_O2_consumed=0.99;//Fraction of O2 Consumed\n", +"rho_cyclohexane=0.779;//Density of cyclohexane at 20 (°C)\n", +"main_pdt_ratio=3/2;\n", +"by_pdt_ratio=(1-main_pdt_ratio);\n", +"stoi_rxn_O2=[0.5 1];\n", +"rho_M=0.650;//Density of Cyclohexane at 155 (°C)\n", +"P_dash=5.8;//Vapour Pressure of cyclohexane at 155 (°C)\n", +"D_reactor=30;//Diameter of reactor (cm)\n", +"h_reactor=50;//Height of reactor (cm)\n", +"myu_20=0.98;//(cp) Viscosity at 20(°C) \n", +"myu_155=0.2// (cp) Viscosity at 155(°C)\n", +"x_O2=6.38*(10^(-6));//Mol fraction of O2\n", +"D_B_by_D_A=0.5;//Assumed value (refer Ex7.7)\n", +"Phi=20;//Refer Fig. 7.7\n", +"n=1/(0.7);\n", +"\n", +"\n", +"//CALCULATION (Ex7.7.a )\n", +"F_O2=(F_air*10^(6)*f_O2_air)/(3600*V_ref);\n", +"delta_N_O2=F_O2*f_O2_consumed;\n", +"F_C6=(F_cyclohexane*10^(3)*rho_cyclohexane)/(3600*M_cyclohexane)\n", +"F_prdts=F_C6*X_conversion*S;\n", +"F_O2_prdts=F_prdts*(main_pdt_ratio*stoi_rxn_O2(1)+by_pdt_ratio*stoi_rxn_O2(2));\n", +"F_O2_remain_used=delta_N_O2-F_O2_prdts;\n", +"F_O2_prdts_conver=F_O2_prdts/(F_C6*X_conversion*S);\n", +"F_O2_remain_used_conver=F_O2_remain_used/(F_C6*X_conversion*(1-S));\n", +"X_O2=10^(0.366*log10(T_K)-3.8385);//O2 solubility from Wild et al. [37]:\n", +"PO2_plus_PN2=P-P_dash;\n", +"P_O2=y_O2*PO2_plus_PN2;\n", +"x_O2=P_O2*X_O2;//Mol fraction of O2\n", +"C_M=rho_M*10^(3)/M_cyclohexane;\n", +"C_O2_star=C_M*x_O2;\n", +"\n", +"//Assume each reactor has 30 L solution\n", +"V_soln_n=30;//Volume of solution in each reactor \n", +"apparent_kLa=(delta_N_O2)/(V_soln_n*No_reactor*C_O2_star);\n", +"F_total=(F_air*10^(6)/3600)*(T_K/T_ref)*(8.2/2.4)*(1/8.2);//The total vapor flow is 8.2/2.4 times the air flow\n", +"CSA_reactor=%pi*(D_reactor^2)/4;\n", +"u_g=F_total/(CSA_reactor*No_reactor);\n", +"//Calculation for predicted value of kLa\n", +"kLa_20=0.16;//From Figure 7.16, for O2–C6H12 at 20 (°C), 2 cm/sec, 5 kW/m3\n", +"T_data=20+T_ref;//Temperature at which data is taken from the table\n", +"D_155_by_D_20=(T_K/T_data)*(myu_20/myu_155);\n", +"Predicted_kLa=kLa_20*(D_155_by_D_20^(0.5))*(u_g/2)^(0.5);\n", +"\n", +"//CALCULATION (Ex7.7.b )\n", +"C_M=rho_M*10^(3)/M_cyclohexane;\n", +"C_B0=(1-X_conversion)*C_M;\n", +"C_Ai=C_M*x_O2;\n", +"Phi_a=(1+(C_B0/(C_Ai*n))*(D_B_by_D_A)^(0.5));\n", +"ratio=Phi_a/Phi;\n", +"\n", +"//OUTPUT (Ex7.7.a )\n", +"mprintf('\n OUTPUT Ex7.7.a');\n", +"mprintf('\n==========================================================');\n", +"mprintf('\nThe value of apparent kLa: %0.2f (sec-1)',apparent_kLa);\n", +"mprintf('\n The value of predicted kLa: %0.2f (sec-1)',Predicted_kLa);\n", +"if (apparent_kLa>Predicted_kLa)\n", +" mprintf('\nThe absorption of oxygen is greatly enhanced by chemical reactions in the liquid film')\n", +" mprintf('\nThe kinetics can be approximated by a first-order expression,the reaction would fall in the pseudo-first-order regime,\nwhere the rate varies with the square root of the oxygen diffusivity and the rate constant.')\n", +"end\n", +"\n", +"//OUTPUT (Ex7.7.b )\n", +"mprintf('\n\n\n OUTPUT Ex7.7.b');\n", +"mprintf('\n==========================================================');\n", +"mprintf('\nThe value of Phi (enhancement factor) %0.4E ',Phi_a);\n", +"mprintf('\nThe value of ratio Phi_a_by_Phi:%0.1E',ratio);\n", +"mprintf('\nFrom the ratio value Phi_a is greater than Phi hence there is no significant gradient for cyclohexane');\n", +"\n", +"// FILE OUTPUT\n", +"fid= mopen('.\Chapter7-Ex7-Output.txt','w');\n", +"mfprintf(fid,'\n OUTPUT Ex7.7.a');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\nThe value of apparent kLa: %0.2f (sec-1)',apparent_kLa);\n", +"mfprintf(fid,'\n The value of predicted kLa: %0.2f (sec-1)',Predicted_kLa);\n", +"if (apparent_kLa>Predicted_kLa)\n", +" mfprintf(fid,'\nThe absorption of oxygen is greatly enhanced by chemical reactions in the liquid film')\n", +" mfprintf(fid,'\nThe kinetics can be approximated by a first-order expression,the reaction would fall in the pseudo-first-order regime,\nwhere the rate varies with the square root of the oxygen diffusivity and the rate constant.')\n", +"end\n", +"mfprintf(fid,'\n\n\n OUTPUT Ex7.7.b');\n", +"mfprintf(fid,'\n==========================================================');\n", +"mfprintf(fid,'\nThe value of Phi (enhancement factor) %0.4E ',Phi_a);\n", +"mfprintf(fid,'\nThe value of ratio Phi_a_by_Phi:%0.1E',ratio);\n", +"mfprintf(fid,'\nFrom the ratio value Phi_a is greater than Phi hence there is no significant gradient for cyclohexane');\n", +"mclose(fid);\n", +"//==========================================================END OF PROGRAM===============================================\n", +"\n", +"" + ] + } +], +"metadata": { + "kernelspec": { + "display_name": "Scilab", + "language": "scilab", + "name": "scilab" + }, + "language_info": { + "file_extension": ".sce", + "help_links": [ + { + "text": "MetaKernel Magics", + "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md" + } + ], + "mimetype": "text/x-octave", + "name": "scilab", + "version": "0.7.1" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} |