A unified correlation for predicting liquid axial dispersion coefficient in bubble columns

Experimental measurements of gas holdup and liquid axial dispersion coeffic ients have been carried out in two bubble columns (column I; D-c = 15 cm an d column II; D-c = 20 cm), operating with co-current upflow of gas and liqu id. In addition, measurement of bubble size was investigated. Peclet number and liquid axial dispersion coefficient were calculated from the means and variances of the residence lime distribution (RTD) curve. The experimental data obtained show that the hydrodynamic of bubble column depends on super ficial gas and liquid velocities, column diameter and the gas flow regime. Present results and the available literature data were used to develop a mo del involving Bo, Re, Fr and Ga for predicting liquid axial dispersion coef ficient. (C) 2001 Elsevier Science Ltd. All rights reserved.