Purifier filter for dust and fume with automatic cleaning backwash of Operation The cartridge filter with cleaning backwash CORAL mod. AIRCOMPACT is composed of filter elements in cartridges encased in a central body airtight, and is designed to be used in the vacuum systems. The dusty air enters from the bottom hopper and, due to the abrupt reduction in speed, the larger particles decant and end up into the collection bin. The finer particles or read date from the body, inside of which the filter cartridges are housed; the polluted air from the outside runs through the cartridge into the interior, so that the dust deposits externally whereas the air flows through the cartridges and exits purified.