<p>A granulating and coating apparatus in which a rotary drum (1) containing powdery or granular material is rotated about the substantially horizontal axis for granulating and/or coating the powdery or granular material. The apparatus is provided with a disk valve mechanism for switching a gas supply or exhaust path to the rotary drum on the operating side of the rotary drum. The rotary drum is provided inside of itself with a baffle means (23) for stirring powdery or granular material and a baffle displacing means (24) for displacing the baffle means. Inside of the rotary drum is provided a temperature sensor (33) for directly measuring a temperature of powdery or granular material. The rotary drum is composed of porous polygonal. Each side of the polygonal drum includes an outer enclosure (6) mounted thereon and individual detachable.</p>
