Granular filter allows the filtration of gas by passing the gas containing the dust particles to be removed through a bed of granular material, for example gravel.
In the case of fixed bed granular filter, a fixed bed is used where the gas flows through the bed and dust particles removed from the gas stream build up within the bed.
Ultimately, the flow of gas in the cleaning direction is terminated and gas flow is reversed to remove the accumulated dust from the filter bed. Subsequently a new gas cleaning cycle is initiated.