Reverse Air Filter Dust Collector

Reverse Air Filters

The RAF is a simple, effective cleaning system. It is designed for high reliability and operates with lower energy use than an equivalent pulse-jet cleaned system. RAF also reduces the possibility that dust can collect inside the structure, reducing fire and explosion risk. RAF is now supported by the market-leading MikroPul-Assist remote monitoring package.


The Reverse Air Filter II (RAF II) uses a continuous cleaning system, avoiding the need for compressed air and unreliable valves. Each bag is cleaned once every 120 seconds using the efficient reversed flow of processed air. This complete and systematic cleaning dramatically reduces the pressure drop across the media as well as the load demands on the complete fan system. Bag life is extended because of the cleaning method. RAF uses two techniques to remove dust: cyclonic separation and media filtration, allowing larger particles to be removed easily before meeting the media.

Features and Benefites

  • Save energy with low pressure drop, low fan HP, recycled clean air
  • Superior operating performance with integral cleaning fan
  • Easy maintenance with walk-in access, top bag removal and sectionalized tube sheets
  • Reduce maintenance costs - no valves, dampers, compressors, or PD pump to maintain
  • RAF collectors can be supported by MikroPul-Assist remote monitoring packages to improve site safety
  • All installed RAF II and RAF-IS filters can be retrofitted with MikroPul-Assist


The RAF-IS Reverse Air Filter is specifically designed for highly combustible dust and high temperature applications. The RAF-IS dust collector is ideally suited for a Coal (including PRB), Wood and Agro material filtration. It combines high performance, low energy use, and reliable and effective reverse-air cleaning in a ledge-less filter housing totally free of internal electrical components. These features make it ideal for flammable dust applications:

  • Meets IS regulations with all electrical components outside the filter housing.
  • Cleaning system recycles the filtered air, so no outside oxygen is introduced.
  • Proprietary Form-lock(TM) bag and cage design ensures positive grounded cages per NFPA 77 code.
  • No flat surfaces where dust can accumulate.
  • Built-in deluge nozzles per NFPA 15 codes.
  • Explosion venting per latest NFPA 68-2002 codes.
  • Involute inlet is clad with replaceable anti-spark wear resistant plates.
  • 60° (70° optional) hopper with flush mounted inspection door prevents dust accumulation.

Downloadable Documents

RAF II Reverse Air Filter

RAF II specs

RAF-IS Reverse Air Filter for Highly Combustible Dust and High Temperature Applications

RAF-IS overview

MikroPul-Assist for RAF