Is it permissible for two immiscible phases to exist at the bottom of a distillation column?
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There is a material that contains water, a product, and a solvent; the boiling point of the solvent is lower than that of both water and the product, and water and the product are immiscible with each other. If the solvent is first completely removed from the top of the distillation column, the water and the product remaining at the bottom of the column will be immiscible with each other; could this affect heat transfer at the bottom of the column and lead to bumping? The reboiler is a thermosyphon reboiler. In actual production, are there cases where the material at the bottom of the tower consists of two immiscible phases? What is it produced? How is heat exchange at the bottom of the tower handled? Everyone is welcome to offer suggestions; thank you!
If water is immiscible with the product, especially when the density of the product is greater than that of water, boiling over can occur easily during the heating process. This is the case in processes such as crude oil distillation. Having worked in the chemical industry for over twenty years, I have never seen, in actual production, a situation where the material at the bottom of the tower consists of two immiscible phases. (Relatively speaking, there might be exceptions; for example, in products that are insoluble in water, there may still be water components present, such as in asphalt.)
Are there any cases where water, solvents, and products are mutually soluble with each other? If present, extraction can be used for separation, while miscible systems can be separated by distillation. Since I am not familiar with the manufacturing process, this is just a suggestion; the actual details should be determined according to the specific process.
They are immiscible; one needs to consider the density, as separation into layers occurs easily. What kind of product can be obtained? If water is allowed to be present in the product, that might be acceptable; but if high standards are required, further separation is necessary. What is this process? If so, it must first involve physical water removal, followed by distillation.