The dusty air enters the lower housing through the intake, where some particles settle and those with slight dust float are trapped by the bag filter. The purified air passes through the filter bags and enters the upper housing via a Venturi tube, then is discharged from the outlet. As dust accumulates on the outer surface of the filter bags, it increases, and when the resistance is within the specified range (usually 80-120 mm water column), the dust on the outer surface of the filter bags must be removed. The cleaning process is initiated sequentially by the controller to activate various control valves. Compressed air from the gas bag passes through the blast tube, causing the bag to expand rapidly for a moment, with the reaction of the airflow causing the dust to fall and enter the ash door, where it is discharged through the ash valve.