A simple question at normal pressure, but it’s not easy to answer
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Someone asked me why the pressure at the bottom of a atmospheric pressure tower cannot exceed 0.8 kilograms, and I answered that question, but I feel it’s not comprehensive enough. Please ask the teacher for a comprehensive answer.
In my personal opinion, it depends on whether the 1-kilogram threshold for pressure vessels is used as a requirement, with a certain margin taken into account
The operating pressure is determined based on the process; 0.8 meets the requirements for the cooler pressure drop and the fuel system pressure.
There is a limit for low-pressure vessels: 1.6 Mpa gauge pressure. Recirculation tanks generally have such a limit; for low-pressure vessels, it’s usually 0.8 Mpa plus atmospheric pressure minus the pressure drop, and that constitutes the upper limit.
As far as I know, the pressure control at the top of the atmospheric distillation column in vacuum distillation processes is not very high; it is generally around 0.6 kilograms. I’m thinking the same thing; if it’s controlled at high levels, I wonder what the effects would be.