What exactly is the dew point at CNG filling stations?
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Dear experts, the requirement regarding the dew point in \"Compressed Natural Gas for Vehicles\" is that, at the maximum operating pressure, the water dew point should not be higher than -13°C. So, what is the corresponding dew point if the maximum pressure is 25 MPa? I can’t help but feel grateful here! ! !
No one will step in; I’ll do it myself. If you don’t believe it, no one will step in
The water dew point requirement at 25 MPa is also -13 degrees, but this is not reliable enough; you should have the water dehydrated to -60 degrees – at the very least, it should be -40 degrees
What you say does seem reasonable, but the dew point of water at 25 MPa should correspond to below -13 degrees under standard conditions.
The purpose of the regulations regarding dew point is to ensure that CNG does not condense under extreme local environmental temperatures, and that is all. The dew point corresponding to a specific temperature should be determined using a psychrometric chart; at standard pressure, it is definitely below -13 degrees.
At standard conditions, the temperature is at least below -40 degrees Celsius. There is a table showing the pressure dew point; 14 kilograms corresponds to a temperature of -40 degrees Celsius, and the temperature is even lower for 25 kilograms