Method and apparatus for renewing gas-entry faces of a panel for gas and granular material contacting

There is provided an improved method and apparatus for renewal of a plurality of faces across which gas enters a panel of a granular material. The panel is for contacting the gas and granular material with each other to effect physical or chemical treatment of at least one of them (for example, to filter dust from a gas or to remove a constituent from a gas by means of adsorption or absorption). In the panel, gas-entry faces are transversely disposed, upwardly spaced, and held in place by supporting members. These supporting members are subjected to a sharp motion in a direction toward the gas-entry faces, causing body movement of the granular material toward the faces, thereby causing moieties of granular material to fall away therefrom. Removal of these moieties and exposure of previously underlying granular material renew the faces. Flat-plate louvers are preferred supporting members.