Vacuum control
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There are some negative-pressure reaction vessels and negative-pressure distillation columns in the project. For vacuum control, it is intended to install a pressure transmitter on the reaction vessels, as well as a shut-off valve behind the condenser and in front of the vacuum pump. To ensure that there are no leaks from the reaction vessels, is it feasible to use the shut-off valve in combination with the range control of the vacuum pressure transmitter? But from a production perspective, it can’t be cut off – there’s no gas flow anymore. Should we install a control valve? I want to figure out whether the vacuum cut-off valves of the reactor and distillation tower are closed, meaning there is no flow anymore
The shut-off valve has been closed, yet the vacuum pump continues to draw air – so why isn’t there any gas flow? The flow still exists; for the pump, closing the valve simply reduces the load on its chamber.
Bro Pig is going to sell you a top-quality vacuum gauge that can detect absolute pressures as low as 1 Pa. Let’s work together to drive your factory’s vacuum pumps to exhaustion, haha{:2_42:}
I mean, for a distillation column, closing the vacuum valve maintains negative pressure, but there is no direction for airflow – does this violate the principles of distillation?
A distillation tower? I’ve never seen one either. The largest vacuum vessels I’ve seen aren’t even as big as the washbasins I use to wash my face... :lol :lol A distillation tower, or a vacuum evaporation vessel – the higher the vacuum level, the more the liquid material evaporates, and thus the higher the production volume. Well then, Nana, why not just let the vacuum pump work at full capacity? There’s no need to use valves to control the vacuum level, right? If it’s really necessary to keep the vacuum level stable, well then, just buy an advanced vacuum gauge from Pig Brother :P. That way, one can adjust the pump speed directly – how simple is that? It saves money too, and the results are excellent..............
Without even a basic process flow diagram, it’s impossible to develop an appropriate control scheme. What the heck is a cut-off valve used to control tower pressure? ? ?
By controlling the vacuum pump, negative pressure can be controlled; it’s the frequency converter from last time
I don’t understand it either; if you want to stabilize the pressure in a vacuum distillation tower, using a shut-off valve definitely won’t work!
What I mean is to close the vacuum shut-off valve after the condenser once the vacuum in the tower is stabilized; if the tower is properly sealed and airtight, it will maintain its vacuum state； Will this have an impact on the efficiency of the distillation tower? ；
This post was last edited by Hao Liang Zhi Le on 2019-11-9 at 11:23. Negative-pressure distillation can be divided into: 1. Processes involving a relatively large amount of non-condensable gases； 2. Contains a small amount of non-condensable gases ； 3. Contains trace amounts of non-condensable gases ； 4. Free of non-condensable gases. For cases 1 and 2, creating a negative pressure through vacuum pump suction is an important method; in such situations it is not possible to completely close the vacuum pump inlet valve. Therefore, the vacuum pump inlet valve should be a control valve, not a shut-off valve ； For cases 3 and 4, it is related to the condensing capacity of the condenser; when the condensing capacity is sufficient, it is possible to consider installing a shut-off valve at the inlet of the vacuum pump, which opens for a certain period of time depending on the vacuum level before closing, or opens at regular intervals before closing.
What was said upstairs is quite clear; the original poster can simply analyze the operating conditions corresponding to the system