2101.     ---------------.  [LEVA, M., GRUMMER, M., WEINTRAUB, M. AND POLLCHIK, M.]  Fluidization of Solid Nonvesicular Particles.  II.  Chem. Eng. Progress, vol. 44, No. 8, 1948, pp. 619-626; Chem. Abs., vol. 42, 1948, p. 7583.

        Fundamental correlations for the fluidization of small particles are developed from experimental data.  The experimental work was carried out with round and sharp silica sands varying in size from 0.01505-0.00202-in. effective diameter.  The flow of air, CO₂, and He through beds of these particles in a 2.5-in. and 4-in. tube was investigated.  A distinction is made between expanded and fluidized beds.  It was found that a bed of fine particles must have a certain minimum voidage before fluidization sets in. This minimum fluid voidage has been correlated with the effective diameter of the bed particles for the various shapes considered.  With the minimum fluid voidage available and the pressure-drop law describing flow of fluids through packed beds, the onset of fluidization may be predicted.  Interpretation of the data permitted the definition of a fluidization efficiency, which may perhaps be used as a criterion for the quality of fluidization operations.  Correlations have been applied with good results to mixed sizes up to 5 individual components.  The slugging behavior of fluidized beds was considered, and an attempt was made to correlate slugging points.  2 typical problems illustrate the applications of the new correlations; 1 demonstrates that the correlations are also valid for the upward flow of liquids through beds of fine particles.