COMPARE SELF CLEANING FILTERS:
Air-Cleaning BlowersTM (ACBs) require no pressurized air for cleaning. In contrast, Compressed-Air-Using “Self-Cleaning” Filter Systems (SCFs) can not function without a directly-connected supply of compressed air, often using it in large quantities.
Self Cleaning Filters must capture and collected all the debris that they remove from the air. ACBs do not need to remove accumulated debris because they do not collect it in the first place.
ACBs cost less to buy compared to other self cleaning filters. Since they are much simpler and smaller, they usually cost less, often much less, to install, and ACBs take up less space, again often much less. In addition, ACBs generally require less ductwork to install and clean than SCFs.
THE ACB DIFFERENCE:
Since ACBs are compact, they can frequently be installed much closer to the point of use. The complications of SCFs often require that they be centrally, and remotely, located. The required ductwork also adds to the work their blowers must do and, consequently, to the consumption of electricity.
Even though they self-clean for a while, self cleaning filters’ internal filter media eventually has to be replaced because the pores in the material become too clogged to blow out sufficiently. ACBs never incur the costs of buying, installing and disposing of filter elements because they do not contain any filter media.
In most cases, ACBs simply discharge the dust and other particles that they remove back where they came from, usually outdoors or into the dusty environment surrounding the application. Since whatever air goes into an enclosure ultimately comes out and back into the original dusty atmosphere, the ACBs do not make any net change to that environment—it retains its original amount of air and dust.
In contrast, since SCFs collect the dust, they usually remove a portion of the dust from the dusty environment. However, that amount can be negligible versus the total amount of dust in the facility in which they are installed so that they make little net change in the overall environment, and their benefits are limited only to the application toward which they are directed.
ENERGY EFFICIENCY:
Electrical consumption per CFM produced generally runs lower, often far lower with ACBs than it does with SCFs, and new designs of ACBs are pushing their required electrical consumption down still further.
By their very nature and their design requirements, self cleaning filters have a difficult time approaching the energy efficiency of ACBs. The principal issue is that they must trade off between the costs of cleaning the filters and running them significantly clogged:
SCFs that use compressed air often, if not usually, designed to run with high pressure losses. Since letting the compressed air constantly is costly and could damage the media, most systems let debris accumulate in the filter media untilthat accumulated dust reaches a pre-set level of clogging (pressure drop). Reaching that point triggers the compressed air to clean the media. A common set point is in the range of 4″ w.g. (water gauge, which is equivalent to about 1250 Pa—pascals). When it reaches that point, the compressed air comes on and runs until the pressure loss reaches another set point, often in the range of 2″ w.g. of pressure loss.