If the heavy components in the feed to the distillation tower increase, how does the temperature at the bottom of the tower change? Why?
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The master said that the temperature of the tower bottom is rising, but he can’t explain why; I’d like some advice
It increases, but it tends to stabilize once it reaches a certain temperature. The liquid level begins to rise, which is related to the boiling point of the heavier components; generally, normalizing the operating conditions of the high-boiling-point substances tower resolves this issue immediately.
The proportion of heavy components in the feed increases, meaning that the proportion of light components decreases. With all other conditions unchanged, especially when the heating rate remains constant, the amount of evaporation decreases, and thus the heat energy consumption also decreases. The excess heat energy is used to raise the temperature of the heavier components; these components have a high heat of fusion and high boiling points, so they do not reach the temperature required for evaporation, which is why an increase in temperature is observed.
To maintain balance, excess reagents need to be removed; by reducing the amount of steam, is it then unnecessary to adjust the reflux?
Reducing the reflux flow and increasing the reboiling volume serve the same purpose, but reducing the reflux flow yields faster results
The proportion of heavy components in the feed increases, meaning that the proportion of light components decreases. With all other conditions unchanged, especially when the heating rate remains constant, the amount of evaporation decreases, and thus the heat energy consumption also decreases. The excess heat energy is used to raise the temperature of the heavier components; these components have a high heat of fusion and high boiling points, so they do not reach the temperature required for evaporation, which is why an increase in temperature is observed.
OK. Thank you, understood
If the proportion of Reconstituted components in the feed increases, at a constant distillation pressure, the temperature at the bottom of the tower will rise. If the reflux ratio remains unchanged, as the tower temperature increases, the temperature at the top of the tower may also rise, resulting in a decrease in the purity of the product； Therefore, the reflux ratio needs to be increased appropriately in operation to reach the previous top temperature of the product, which will solve the problem.
If that’s the case, won’t the content of heavy components at the top of the tower be high?
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