Quantitative study of the gas-solids flow and its heterogeneity/nonuniformity in a 14 m two-dimensional CFB riser reactor

Modelling, design and operating of the circulating fluidized bed (CFB) reactors require quantitative studies on the flow structure and hydrodynamic heterogeneity which has a significant influence on the process reactions. This study comprehensively investigates the axial and lateral distribution of the solids concentration with superficial gas velocity of 5-9 m/s and solids circulation rate of 100-300 kg/m2s in a pilot CFB reactor of 14 m high. Empirical models are developed based on the above experimental data for both axial and lateral solids concentrations. The predicted values by the proposed correlations are in good agreement with the experimental data within deviation of 10-20%. An empirical correlation to calculate RNI (Radial Nonuniformity Index) is proposed in order to quantify the nonuniform of the gas-solids flow. Using RNI empirical correlation, the flow development can be also calculated quantitatively showing a good agreement with the results obtained from the data of solids concentration di...