To remove harmful components such as dioxins to the full extent by efficiently utilizing an adsorbent employed for a packed-layer adsorption- regeneration method at the time of adsorptive removal of harmful components such as dioxins of a waste gas.

This waste gas treatment apparatus comprises a dust collecting apparatus 2, a packed-layer 4 filled with a carbon-based adsorbent in the downstream side of the apparatus 2, a regeneration apparatus 6 for regenerating the adsorbent whose adsorption capability is deteriorated, and a separation apparatus 7 for separating a regenerated adsorbent, a powdered adsorbent, and dust. A blowing apparatus 9 to blow the powdered adsorbent containing dust to the inlet side of a duct of the dust collecting apparatus 2 is installed in the waste gas treatment apparatus.