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solving ODE..set of differential equations
Posted 10 juil. 2016, 10:35 UTC−4 Chemical Reaction Engineering Version 4.4 2 Replies
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( dH)/dt=-R_H ; where R_H=A_H*H*exp((-E_H)/RT)
dM/dt=2/3 R_H-R_(M ) ; where R_M=A_M*M*exp((-E_M)/RT)
dW/dt=3R_M-R_(W ) ; where R_W=A_W*W*exp((-E_W)/RT)
( dF)/dt=-R_(W );
dC/dt=-( 1/3 R_H+R_(M )+R_(W )) ;
ρC_P ∂T/∂t=∂/∂x(K_eff ∂T/∂x)+∑_(i=H,M,W,C)▒〖R_i 〖∆H〗_i 〗
at top
- K_eff ∂T/∂z= 0
at bottom
- K_eff ∂T/∂z= σ ε (T_a^4- T^4 )
2 Replies Last Post 15 juil. 2016, 01:39 UTC−4
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Posted:
8 years ago
Hello Sooraj,
You may want to clarify for Discussion Forum users what questions you have.
Jeff
You may want to clarify for Discussion Forum users what questions you have.
Jeff
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Posted:
8 years ago
Hematite to magnetite: 3Fe2O3 + CO = 2Fe3O4 + CO2
Magnetite to wustite: Fe3O4 + CO = 3FeO + CO2
Wustite to iron: FeO + CO = Fe + CO2
Boudouard reaction: CO2 + C = 2CO
these reactions should be solved using chemical reaction engineering module.
First order kinetics has been assumed here. ie using Arrhenius equation. as defined in that module. values of the constant has been defined below,
A_H=10^19/s A_M=10^18/s A_W=10^14/s
E_H=580 KJ/mole E_M=580 KJ/mole E_W=390 KJ/mole
∆H (H→M)=-16 KJ/mole
∆H (M→W)=42 KJ/mole
∆H (W→Fe)=-17 KJ/mole
∆H (C-gasification)=172 KJ/mol
σ=5.667×10^(-8) watt/m^2-K
ε=0.8
T=1,500K
Density (kg/ m3):
H= 5,200; M= 5,160; W=5,500; Fe= 7,800; C= 2,267
Heat capacity Cp (J/ kg-K):
H= 100; M= 100; W=80; Fe= 65; C= 80
where H= Hematite, M=Magneite, W=Wustite, F=Iron, C =Carbon.
I have already posted the set of first order kinetics eqs earlier
Magnetite to wustite: Fe3O4 + CO = 3FeO + CO2
Wustite to iron: FeO + CO = Fe + CO2
Boudouard reaction: CO2 + C = 2CO
these reactions should be solved using chemical reaction engineering module.
First order kinetics has been assumed here. ie using Arrhenius equation. as defined in that module. values of the constant has been defined below,
A_H=10^19/s A_M=10^18/s A_W=10^14/s
E_H=580 KJ/mole E_M=580 KJ/mole E_W=390 KJ/mole
∆H (H→M)=-16 KJ/mole
∆H (M→W)=42 KJ/mole
∆H (W→Fe)=-17 KJ/mole
∆H (C-gasification)=172 KJ/mol
σ=5.667×10^(-8) watt/m^2-K
ε=0.8
T=1,500K
Density (kg/ m3):
H= 5,200; M= 5,160; W=5,500; Fe= 7,800; C= 2,267
Heat capacity Cp (J/ kg-K):
H= 100; M= 100; W=80; Fe= 65; C= 80
where H= Hematite, M=Magneite, W=Wustite, F=Iron, C =Carbon.
I have already posted the set of first order kinetics eqs earlier