FURNACES OR REACTORS FOR THE TREATMENT OF SOLIDS SUSPENDED IN GASES, AND MORE PARTICULARLY, WHEREIN A LAYER OF FINE SOLIDS SUCH AS METALLIC ORES, DOLOMITE, LIME-BEARING SLUDGES AND OTHER SUCH MUDS, CARBON BEING ACTIVATED AND ANY SUCH SOLIDS TO BE SUBJECTED TO ROASTING, OXIDATION, REDUCTION, DECOMPOSITION OR DISSOCIATION AND TO NODULIZATION; IN WHICH LAYER SUCH FINE SOLIDS ARE MAINTAINED IN MOBILE SUSPENSION BY AND IN THE PRESENCE OF UPFLOWING CONTACT GASES PROVIDED FOR EFFECTING A CHEMICAL OR...