A very amateurish question: What is the significance of the reflux ratio, or distillation, for azeotropic materials?
Thread Content
As the title suggests, for materials that are azeotropic, is it meaningful to adjust the reflux ratio?
Azeotropy refers to the situation where the composition at the top of the tower is that of an azeotrope; upon condensation after leaving the tower, liquid-liquid separation may occur. In such cases, it is possible to choose either the light phase or the heavy phase component to be sent back into the tower, and adjusting the reflux ratio becomes very important in this context
Hmm~ this is azeotropic distillation! I’m sorry I didn’t make it clear earlier; what if there is no distinction between forms? Is the reflux ratio meaningful?
Without phase separation, it just doesn’t make sense in my opinion!
This problem has been bothering me for a long time. I agree with what was said above, such as the distillation of ethylene glycol and water
Well, actually I think it’s meaningless too. But I have three materials—A/B/C. Among them, A has a boiling point of 200°C. The boiling point of B and C together is 99°C. The design institute proposed a scheme in which B and C are azeotropically removed, leaving components A and B at the bottom of the tower. There is reflux shown on the process flow diagram. So my recirculation is mainly to allow the heavier components to sink. But what are those heavier components? B? Still A?
The fundamental purpose of distillation is to achieve equilibrium among the various components within the tower through reflux; without reflux, can it be considered distillation? Therefore, the reflux ratio must be adjusted appropriately to save energy while producing qualified products!
The Reorganization component is of course A; reflux is used to minimize the fraction of A in the overhead distillate, and then another column is employed to separate B from C.
Adjusting the reflux ratio has no effect on azeotropic distillation; since the top of the column already has an azeotic composition, increasing the reflux ratio will not change the product at the top. In such cases, what needs to be adjusted is the operating pressure, or an azeotrope agent should be added to disrupt the azeotic composition