THE FLUIDIZATION PROCESS OF BINARY MIXTURES OF SOLIDS: DEVELOPMENT OF THE APPROACH BASED ON THE FLUIDIZATION VELOCITY INTERVAL

The main characteristic of the fluidization process of particulate mixtures is the interaction between bed suspension and segregation–remixingdynamics of their components.On addressing the fluidization properties of binary beds of solids differing either in particle density or diameter, the paper shows howinterpretations based on definition of a minimum fluidization velocity of the mixture can lead to erroneous conclusions about the influence playedby system variables on their behaviour. An alternative method of investigation is followed which takes into consideration the existence of a finitevelocity interval, bounded by the “initial” and “final fluidization velocity” of the mixture, along which the whole process of fluidization has place.The results of a wide series of experiments demonstrate that this alternative approach allows recognizing the independent variables of binaryfluidization; they also highlight the differences of behaviour between density- and size-segregating beds.