Abstract: In a method of thermal treatment of particles, the particles are blown into a hot gas stream by means of a reactor blower. In a circle around a fuel jet and through an entry opening the particles are blown through a diffuser into the bottom of a vertically oriented cylindrical reactor chamber of a suspended gas rector. They are passed through an exit opening at the top of the reactor chamber. During this process the fuel gas stream, which is produced by a burner and is directed into the reactor chamber, forms a convective stream with the particles located therein. Particles that exceed a certain predetermined maximum size are fed into a part of the reactor chamber that is above the diffuser.