For water ring vacuum pumps, by using ethylene glycol instead of circulating water, by how much can the vacuum level be improved?
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This post was last edited by weibinaaa on 2015-6-26 at 15:40. For water ring vacuum pumps, by how much can the vacuum level be improved if ethylene glycol is used instead of circulating water? Does anyone know?
The idea is good, but I think safety should also be taken into consideration!
First, you need to determine whether the material of the vacuum pump is resistant to ethylene glycol corrosion; secondly, you must consider how to handle the waste liquid； It is recommended to improve the vacuum level from other aspects, such as cooling the working fluid, adjusting the gaps, and checking or replacing the valve plates.
Haven’t seen it used like this before! :L:L:L:L
The maximum degree of vacuum can be calculated using the saturated vapor pressure of the ethylene glycol-water system, and this is dependent on temperature. The final residual pressure is the vapor pressure of the ethylene glycol-water system at the operating temperature.
The maximum vacuum level can be calculated using the saturated vapor pressure of the ethylene glycol-water system; this represents only the ultimate vacuum level, and it is also dependent on temperature
I have considered using oil instead of water, but the specific circumstances require reference to the manufacturer and usage conditions. Everyone, please see if you can provide it
The last edit to this post was made by symc on 2015-7-8 at 12:57. For a single-stage liquid ring pump, the pressure limit will not be lower than 3 kPa(a). My previous answer wasn’t precise enough; to clarify, no matter what concentration of ethylene glycol is used, it will not cause the pressure limit of a single-stage liquid ring vacuum pump to drop below 3 kPa(a). Additionally, using ethylene glycol as the working fluid increases the shaft power required……
Theoretically, all of them can be used; first calculate the saturated vapor pressure to compare, and then try them out in practice for comparison
It is necessary to consult the manufacturer to determine whether the vacuum pump is suitable for this medium (parameters, corrosion issues)
The answer upstairs is more appropriate. In my opinion, using ethylene glycol instead of circulating water does not increase the vacuum level, because both ethylene glycol and circulating water are fluid media used to create a negative pressure at the center of the impeller; in other words, they are the media through which energy is obtained in the centrifugal impeller.