Calculation of the degassing (desorption) operation condition for control valves
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This post was last edited by “Malaysia with Big Bow” on May 8, 2016, at 23:20. Hello everyone. As the title suggests, I have no idea how to calculate or determine the appropriate type of control valve for deaeration purposes. I’d like to ask for advice here. During the operation of the plant, there may be various types of wash towers, absorption towers, etc.; within these systems, liquids absorb a certain amount of gas under specific conditions, and when a pressure drop is created by control valves, a certain amount of gas will be released. This is different from cavitation flashing, in which both the liquid phase and the gas phase are of the same substance but in different phases. Desorbing gases and liquids generally belong to different categories of substances. How should the selection of control valves be handled in such a situation?
Well, is no one answering? Bear it myself
If the gas content is high, the volume of the medium will increase. So if this portion of gas is not taken into account when selecting the valve, the valve chosen will be relatively small
The amount is small; ignore it! The quantity is too large; it’s not allowed, right?
There is a condition in the process where, in a certain tower-type container, the liquid enters from the top while the gas enters from the bottom. Use a liquid to wash away a certain component in the gas. Under certain temperature and pressure conditions, liquids can absorb large amounts of gas. Since the downstream equipment needs to collect the components carried away by the bottom liquid of the tower. The pressure at the downstream equipment will be relatively low. Therefore, the pressure difference across the control valves between the upstream and downstream equipment is relatively large. The mass ratio of the generated gas to the liquid before the valve can reach 0.5~1%. With such a ratio, a large amount of gas is generated, which already affects the calculations for the control valve.
Saved. Same question – I really hadn’t noticed this before.
This is basically also a question with no solution~~~~ Usually, cavitation calculations are done, but there’s a risk that things might just happen by coincidence. . . If you have any information, remember to share it with each other