Although a wide variety of filters can be categorized as cartridge filters, they all share a few distinguishing features. First, cartridge filters consist of two basic components, the filter cartridge and the cartridge housing. Also, unlike certain filter types, the filter media can be removed and replaced with a new filter cartridge.
Cartridge filters can be used to remove contaminants from a complete range of fluids, including water, oil and air. It is the nature of the design, rather than the nature of the filter media, that defines a cartridge filter. Virtually any media can be used in a cartridge filter, from cotton and polypropylene to metal wire. The mesh of the filter media can be as fine as a fraction of a micron, thereby allowing the filter to capture even micro-organisms like Giardia and Cryptosporidium. Certain bacteria and viruses, however, are able to pass through even some of the finest filters. Other, more complex filter media are available, including activated carbon, reverse osmosis membranes for ion-removal and semi-conductor grade resin cartridges.
Cartridge filters and housings are rated for different flow rates, temperatures and pressures. Generally, the finer the mesh of the filtration media, the lower the maximum flow rate. In addition, certain materials may not be suited to certain temperatures or pressures, and may rapidly degrade when subjected to extreme conditions. Filter manufacturers should be consulted to determine acceptable conditions for the filter, as well as the life of the filter cartridge. Filter media that have reached the limit of their effectiveness and longevity regularly become detrimental to the entire system in question, and may provide a breeding ground for the same organisms that they are meant to eliminate.
An extensive range of industries rely on cartridge filters, from automotive to pharmaceutical. They are used in everything from water purification to cleanroom operation, and are effective means of removing a wide assortment of contaminants. Operating conditions tend to vary by application, and filter standards therefore vary per manufacturer, although standards are widely used. A filters absolute-rating, for example, indicates that particles of a certain size should be unable to pass through it. However, invasive particles are rarely of a uniform size, and certain shapes may be able to pass through the filter unobstructed.
Read more: More about Cartridge Filters