Bag Filter:
A bag-house (BH, B/H), bag filter (BF) or fabric filter (FF) is an air pollution control device that removes particulates out of air or gas released from commercial processes or combustion for electricity generation. Power plants, steel mills, pharmaceutical producers, food manufacturers, chemical producers and other industrial companies often use bag-houses to control emission of air pollutants. Bag-houses came into widespread use in the late 1970's after the invention of high-temperature fabrics (for use in the filter media) capable of withstanding temperatures over 350 °F.
Unlike electrostatic precipitators, where performance may vary significantly depending on the process and electrical conditions, functioning bag-houses typically have a particulate collection efficiency of 99% or better, even when the particle size is very small.