Part 2: Are your filters ready for the next big storm?

Most gas turbine air intake systems have a stage to remove large rain droplets from the air stream, typically greater than 5-10 micron. Smaller droplets need to be removed by the final filter stages of the intake system. Camfil has numerous filters which utilize hydrophobic filter media and have design features that prevent water droplets and dissolved contaminants from entering the engine. Figure 1 shows the optimum static final filters that prevent water migration.

Graph 1 illustrates the results of a deluge test which measures filter pressure drop (dP) over time while the filters are continuously sprayed with water at 2500 CFM and 0.5 LPM² flowrate. Four filters were tested: Camfil’s 12” CamGT 4V-300 rated an F9 efficiency, Camfil’s 24" CamGT 3V-600 E11³, two 12" competitor F9 filters, and one 17" competitor F9 filter. Both CamGTs were superior in performance due to the features outlined in Figure 1, however, the media depth of the CamGT 3V-600 filter allowed it to maintain the lowest and most stable dP when challenged with high water volume, even with its higher efficiency. Further, neither CamGT leaked, whereas the rest showed signs of bypass in under four minutes.

The risk of bypass decreases when there are filter stages protecting the final filter, and for this reason, Camfil recommends a multistage static filtration system for wet and humid area. Inlet filter systems which have horizontal filter cartridges, or a "Cross Flow" configuration, however. have an extra challenge in that water can accumulate in the media pleats on top of the filters. In this case, water and contaminants could penetrate through standard media. If a cartridge filtration system already exists at your site, Camfil offers a robust design and hydrophobic media options that will prevent water penetration and keep the engine clean:

¹ Part 1

² Liter per minute

³ An F9 or E11 efficiency is not recommended for every site. Depending on your environmental conditions, the efficiency requirement will vary. Request a site analysis to determine the optimum filtration solution.