In the case where fluid flows from a high-level tower to a low-level receiving tank, how can negative pressure be prevented from forming inside the tower?
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In the case where fluid flows from a high-level tower to a low-level receiving tank, how can negative pressure be prevented from forming inside the tower? It can be approached from the perspective of self-control or by installing some small devices; thank you
Under normal conditions, water is pumped into the tower; the vent valve is closed while the discharge valve is open. But due to the height of the tower, could negative pressure be generated inside it? ?
Negative pressure is likely to occur; install a breathing valve
Is it the process medium in the high-level tower that determines whether a breathing valve is used or not? Is the gas phase flammable and explosive? Is the medium just water? What is the design pressure of the tower? It is recommended to create an arch shape in the pipe arrangement to form a liquid seal ； If the medium is just water and air, adding a breather valve is also possible
But this will also come into contact with steam; it’s a pressure vessel – can it be equipped with a breathing valve?
The liquid seal seems to be useless as well; it causes siphoning
But this will also come into contact with steam; it is a pressure vessel, and the liquid is flammable and explosive. Can a breathing valve be installed?
Pressure vessel? What is the operating pressure? During normal operation, if it is running continuously, it is sufficient to maintain a stable liquid level. The liquid level controls the opening degree of the drain valve.
Breather valves are generally used in containers at atmospheric pressure. Since your container is under pressure and the liquid phase is flammable and explosive, it is recommended to install a level control valve on the liquid outlet pipe; as an extra precaution, a shut-off valve can also be added； Also, will the liquid phase emit a vapor phase or undergo flash evaporation once it enters the high-pressure tower? If so, in addition to an exhaust system, the vapor space will also be equipped with a vacuum break control valve (with proportional control); that is, when the pressure drops too low, a signal from the pressure transmitter at the top of the tower will trigger the supply of positive pressure air to restore the pressure. The nature of this supplementary air should be similar to that of the vapor phase inside the tower, and it should not react with it