distillation
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May I ask: Is there any relationship between the feed temperature of a distillation column and the operating temperature of the column? Could it be lower than the top temperature of the column or higher than the bottom temperature?
Typically, distillation systems are equipped with a reboiler to control the feed temperature. The feed temperature has a direct impact on the operating temperature, which in turn affects the vapor-liquid equilibrium within the distillation column. Could it be lower than the temperature at the top of the column or higher than the temperature at the bottom? This is certainly very likely; poor control of the steam flow rate in the reboiler, or fluctuations in steam pressure and temperature, can all affect the temperature of the material fed into the tower. I don’t understand what you mean!
I recently saw the design parameters of a distillation column: its feed temperature was 136 degrees, and the bottom temperature was 131 degrees. Does this meet the requirements for distillation operations?
At atmospheric pressure or reduced pressure, how many distillation columns are there? The feed temperature is related to the operating temperatures of the columns; generally, it is lower than the bottom temperature of the columns and close to the top temperature.
It is possible; too low a value means cold feed, and the reactor bottom requires more steam. Too high means a saturated steam feed or a superheated steam feed; thus, significant cooling is required at the top of the tower, while less heat is needed at the bottom of the tower
It makes sense – it’s normal for the temperature at the bottom of the tower to be lower than the temperature of the material entering the tower. This indicates that distillation can take place directly without the need to use a reboiler to raise the temperature. The liquid phase goes directly to the next stage or is recycled, and it is likely that the product to be recovered is present in the gas phase rather than the liquid phase.
There is more or less some connection between them; it’s impossible for there to be no impact at all! !
It is best to control the feed temperature at the bubble point of methanol, that is, around 65 degrees; however, it should not be too high or too low, as this can affect consumption. Keeping it near the bubble point is the optimal setting.
The distillation design mentioned by the original poster includes five types of feed conditions: 1. Bubble-point feed, 2. Cold feed, 3. Vapor-liquid mixed feed, 4. Saturated steam feed, 5. Superheated steam feed. Knowing these helps to easily understand what happens when the temperature is higher than the top or bottom temperature of the system. Generally, bubble-point feed is chosen (that is, the material at the feed plate does not vaporize nor condense)
1. Saturated feed 2. Cold feed 3. Vapor-liquid mixed feed 4. Saturated steam feed 5. Superheated steam feed. Knowing these points makes it easy to understand what happens when the temperature is higher than the top or bottom temperature limits. Generally, saturated feed is chosen (that is, the material on the feed plate neither vaporizes nor condenses)
Feed at the bubble point is certainly good, but with improved technology now, it’s possible to feed at a temperature other than the bubble point