It is possible to use a coalescing media to promote coalescence of the water droplets. These media provide large surface area upon which water droplets can collect. The most common coalescing media is wood shavings or excelsior, which is referred to as a “hay section.” The wood excelsior is tightly packed to create an obstruction to the flow of the small water droplets and promote random collision of these droplets for coalescence. When the droplets are large enough, they will fall out of the flow stream by gravity.
It is possible that the use of a hay section will allow lower treating temperatures. However, these media have a tendency to clog with time and are difficult to remove. They are no longer in common use.