In the following process, the lower the temperature at the top of the vacuum tower, the lower the vacuum degree at the top, is that correct? Why?
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In the following process, the lower the temperature at the top of the vacuum tower, the lower the vacuum degree at the top, is that correct? Why?
Is it true that according to PV=nRT, the lower the temperature, the lower the pressure?
No. Low tower top temperature: 1) The vapor load at the tower top is low, which in turn reduces the vacuum pumping load; the pressure drop in the pipelines also decreases, facilitating an increase in the vacuum level ； 2) At lower temperatures, the saturated vapor pressure of water is correspondingly lower, which should also help to increase the vacuum level. I’m not sure if the above understanding is correct?
Incorrect. The lower the vacuum level, the higher the temperature at the top of the tower.
1) The vapor load at the top of the tower is low, so the vacuum pumping load is correspondingly reduced, which helps to improve the vacuum level； 2) At lower temperatures, the saturated vapor pressure of water is correspondingly lower, which should also help to increase the vacuum level.
I think it’s correct! I won’t mention the reason. It’s similar to when the final boiling point is actually lower than the 98% distillation temperature point.
That’s correct; without taking into account factors such as the pumping speed of the vacuum pump and the maximum achievable vacuum level, the lower the temperature at the top of the tower, the lower the evaporation temperature will be, and consequently the saturated vapor pressure will also be lower. As the temperature drops, the vacuum level inevitably decreases; otherwise, no evaporation would occur
7th floor is correct. But the vapor pressure of the cooling medium and the issue of ultimate residue also need to be considered
As the vacuum level decreases, the residual pressure inside the tower increases, making evaporation more difficult
No, the temperature at the top of the tower is low, the vacuum level is high, and the residual pressure at the top is low
The top temperature is low; there’s no oil at the tower top. Is the top side stream not dry? Can the vacuum level still be high on a dry plate? Besides, if the temperature is low, can your structure withstand corrosion from leaks?