Haffmans DPT

In order to avoid the potential for any humidity present in the gas to freeze during
liquefaction, which could cause a shutdown of the gas production plant, the humidity
of the gas needs to be so low that no ice crystals are formed at these low operating
temperatures.

The Dew Point Tester, type DPT, accurately measures the condensation temperature of
humidity present in CO2 or other gases. The DPT is properly flushed with gas and a low gas stream is set. The cup of the instrument is filled with acetone; cooled down with dry ice, and stirred with the temperature probe. When condensation appears on the cup, the temperature displayed is the atmospheric dew point.