I have a nitrogen gas stream that is wetted using water at 50°C in a bubbler tank , after that I need to calculate how much dry nitrogen gas has to be added to get a dew point of -20°C.
I have found that the vapor pressure of water at 50°C is 123mbara. When the tank is at 1200mbara the fraction of water vapor should be 123/1200, is this correct ?
How do I calculated the dew point of the wetted stream when I have only the fraction ?