TWO PHASE GAS LIQUID FLOW IN PACKED BEDS / FLUIDIZED BEDS

Abstract

This dissertation presents the hydrodynamics of gas-liquid-solid fluidization with cocurrent upward flow of gas~~ and liquid with liquid as the continuous phase studied in a 19 cm ID and 270 cm high Perspex column for air-water-glass beads system.The superficial gas and liquid velocities studied covered the range of 0 -1.1 cm/s and 0 - 3.64 cm/s respectively.Nearly spherical glass spheres having narrow granulometric distribution with average diameters 2.50, 2.56, and 3.70 mm were used in the study. Effect of gas and liquid velocity on phase holdup, quality of fluidization and bed expansion/contraction were measured and the results obtained were found in full conformity with the reported trend in the literature. The ° existing empirical correlations for predicting bed porosity gas and liquid holdups were compared with the experimental results.-It has been found that very few of the existing empirical correlations lie within ±10 to ±20 % deviation from the experimental results while others -showed marked deviation. Correlation of Saberian-Broudjenni et al.(1987) for predicting bed porosity was modified to fit our experimental data within ±10 % deviation. Qualitative description of the hydrodynamic characteristics has been described at length. A Fortran-77 program is developed to carryout the above analysis based upon pressure gradient method of calculating phase holdups.