A hydrodynamic study of conical spouted beds equipped with draft tubes of different configurations have been carried out for fine and coarse particles belonging to Geldart groups D and B, respectively. The draft tubes used are conventional non-porous tubes and open-sided tubes, and runs have been carried out following a design of experiments in order to ascertain the effect of the draft tube geometry on the operating pressure drop and peak pressure drop. Furthermore, runs have been carried out without tubes to compare the results obtained with those obtained with the two types of tubes. The results evidence that the geometry of the draft tube influences the operating pressure drop and especially the peak pressure drop and, therefore, the hydrodynamics of conical spouted beds.