Maintaining Compressed Air, Gas & Steam Filters and Replacing Filter Cartridge Elements

Compressed air is one of the most expensive utilities to employ and its true cost is commonly overlooked in many plant operations. Proper maintenance of your compressed air system is critical for controlling costs and keeping them from rising unnecessarily during operation. Improper filter maintenance reduces the output of compressed air flow due to the loss of pressure caused by restrictive dirty or spent cartridges. In short, depleted elements exhibit high differential pressures (the pressure drop between incoming, unfiltered compressed air from the compressor source and the resulting pressure after filtration). In addition to controlling costs, proper maintenance reduces the oil and dirt in your compressed air lines; contaminants that would otherwise be in contact with your final product!

Element Life of Particulate Filters

Of course, the lifespan of element cartridges varies depending on the application, run cycles, and operating environment of the filter or filters. The simplest way to monitor and determine the end of the usable lives of coalescing filters, pre-filters, and activated carbon filter cartridges is to employ the use of differential pressure gauges. When the differential pressure rises too high, it signals that the effective life of the element cartridge has reached its end. High differential pressure at the filter indicates a saturated or blocked cartridge or cartridges (depending on your filtration configuration), thereby restricting the output air pressure. In addition to letting you know when your filter cartridge element is blocked, differential pressure gauges also help to isolate and determine whether the filter cartridge is actually the culprit for pressure drops in your overall system. As a general rule of thumb, your pressure drop from the compressor to the point of use should not exceed 10 percent. Continuing to use a saturated filter element beyond its effective life invariably leads to lower output pressure, as well as increased cost of operation.

Replacing Elements for Sterile Filters

Sterile filter elements operate differently than standard coalescing filters and have unique expectations with respect to their filtration characteristics. Whereas the coalescing filters and pre-filters remove particulates, oil, and water, sterile filter elements remove only bacterial contaminants. Properly configured, your complete sterile system setup should have a dryer to provide a moisture-free atmosphere in which the sterile element operates.