In my 16 years with in the compressed air industry, I never thought I would have to deal with steam other than with a steam turbine. As the Parker|Balston Product Manager I had to now learn about something new, Steam Filtration.
Without going into great detail, I have learned there are two different types of steam, Wet Steam and Dry Steam. When a boiler generates steam it heats up the water creating bubbles, these bubbles rise up and breakthrough the service pulling water droplets into the steam. The steam is now partially wet. (Note: this is not the case if a super-heater is used to create super-heated Steam)
Steam dryness has affect on the total amount of transferable energy contained within the steam which affects the heating efficiency and quality. The higher the the saturation, the less efficient.
Wet Steam also can have an affect on how steam is filtered. With wet steam the water molecules can condense within the filter housing, the water collects preventing the filter element from removing impurities. With most steam filter manufacturers the recommend a drain trap before and after the filter in hopes to keep the water from collecting within the filter housing.
Parker|Balston has sold the issue of water collecting within the filter housings by designing a steam filter that will remove condensed water. Steam first enters the housing and moves into an expansion chamber, where much of the condensate is removed from the steam by the abrupt change in flow direction and velocity. The steam then flow upward in the housing, through the Filter cartridge, and downward to the exit port. The water draining from filter cartridges and expansion chamber is then removed from the filter housing through a automatic condensate drain.
