Abstract: A processor for particulate material including a cylindrical vortex chamber, a main inlet duct communicating with the chamber at one otherwise closed end for supplying particulate substance in a direction substantially tangential to the interior surface of the vortex chamber and preferably inclined toward the other end, with the cylindrical portion of the vortex chamber being provided with a number of further inlets for the supply of active medium consisting essentially of slits in the vessel wall, with adjacent portions of vessel wall being bent out of the cylindrical curved plane, forming, by such bent portions, inlets which will direct the active medium into the vortex chamber in a tangential and inclined direction similar to the preferred direction of the inlet duct. A particulate material outlet and active medium outlet are also provided.