McCabeThiele module
This class is used to graphically solve binary distillation problems using the McCabeThiele method.
Brief mathematical intro
The equations used for the solution are:
Enriching operation line
\[
y_{n+1} = \frac{R}{R+1} x_n + \frac{1}{R+1} x_D
\]
Stripping operation line
\[
y_{m+1} = \frac{L_m}{V_m} x_m + \frac{W}{V_m} x_W
\]
Feed operation line
\[
y = \frac{q}{q-1} x - \frac{1}{q-1} x_F
\]
Where
\(y\), \(x\) : Molar compositions in the vapor and liquid phase respectively.
\(n\), \(m\) : Step in the enriching and stripping section respectively.
\(R = L_n/D\) : Reflux
\(W\) : Bottom liquid product.
\(L\), \(V\) : Liquid and vapor flux in the column (constant in every step).
\(q\) : mole fraction of the liquid in the feed.
\[
q = \frac{heat\enspace needed \enspace to \enspace vaporize \enspace 1\enspace mol \enspace of \enspace feed \enspace at \enspace entering \enspace conditions}{molar \enspace latent \enspace heat \enspace of \enspace vaporization \enspace of \enspace feed}
\]
Example
# importing fqlearn library
from fqlearn.McCabeThiele import McCabeThiele
model = McCabeThiele()
# Set compounds
model.set_data(compound_a="methanol", compound_b="water")
# Set desired compositions in the distilate (xD) and the Bottom liquid (xW)
model.set_compositions(xD=0.94, xW=0.05)
# Set feed values
model.set_feed(q=0.5, xF=0.5)
# Solve the model
model.solve()
# Print results
model.describe()
# Plot results
model.plot()
After executing the code above you will see:
- El reflujo mínimo es de: 0.7480780119884876
- La composición líquida de salida: 0.05
### Composición de entrada y salida en cada etapa:
- Etapa 1: Entrada = 0.9400, Salida = 0.9400
- Etapa 2: Entrada = 0.8783, Salida = 0.9400
- Etapa 3: Entrada = 0.8783, Salida = 0.9074
- Etapa 4: Entrada = 0.7933, Salida = 0.9074
- Etapa 5: Entrada = 0.7933, Salida = 0.8624
- Etapa 6: Entrada = 0.6840, Salida = 0.8624
- Etapa 7: Entrada = 0.6840, Salida = 0.8046
- Etapa 8: Entrada = 0.5611, Salida = 0.8046
- Etapa 9: Entrada = 0.5611, Salida = 0.7396
- Etapa 10: Entrada = 0.4316, Salida = 0.7396
Número total de etapas: 9