Modelling of a liquid fluidized bed separator using 1D segregation-dispersion model under continuous process conditions
摘要
A 1D continuous segregation-dispersion model for liquid fluidized bed separators (LFBSs) has been proposed. The 1D model was implemented using a Fortran 77 code to simulate LFBSs and describe the hydrodynamics characteristics of a mono-component and a multicomponent system. At first, a single particle species, 1400 kg/m3, was fluidized at a fluidization velocity of 0.0229 m/s for the feed fluxes 0.001 and 0.002 (m3/m2s). The solid volume fraction across the bed height was drawn from simulation results. The results showed that the system attained a maximum concentration of 0.226 exhibiting a higher concentration of solid particles near the base. Whereas, in the dilute region the concentration of solid particles was 0.038. The simulation results were validated successfully through flux curve analysis and an analytical expression. After successful validation, a multicomponent system, typically a coal feed, comprising 35 diverse particle species in the size range − 2.0 + 0.25 mm and densities ranging 1300 to 2200 kg/m3 was simulated using the 1D model. Partition curves were generated from simulations and the D50 and Ep values were obtained from the partition curves to characterize the separation performance of the device. Moreover, the D50 and Ep values matched very well with the published experimental results. Overall simulation results were in good agreement. Furthermore, the D50 and Ep values of the LFBS were compared with the published values of the Reflux Classifier to demonstrate the difference in the segregation performance of both devices and hence the model robustness.