The dust-containing gas is conveyed by the fan into the dust collector, the dust is filtered on the high-density drum filter cloth, and the suction is periodically rotated and adsorbed, and the dust is discharged to the storage barrel, and then the screw is extruded or conveyed to the production line for reuse; The latter gas is filtered twice to reach clean gas, which is drawn by a negative pressure frequency conversion fan and then discharged into the atmosphere.