Hydrodynamic properties of a cold model of dual fluidized bed gasifier: A modeling and experimental investigation

Abstract

Gasification in dual fluidized bed gasifiers (DFBGs) has been acknowledged to be one of the promising technologies. The hydrodynamic characteristics play a vital role in the design and development of such reactors, therefore, their modeling is worthwhile. In this study a hydrodynamic model considering each section of the DFBG system – riser, cyclone, standpipe, loop-seal, bubbling fluidized bed (BFB), connection with L-valve (lower connection) – was developed to predict the pressure drops and solid circulation rates. The model parameters were fitted with the experimental data obtained from the cold model of DFBG in order to improve the predicted results. A power law model was developed for the friction factor to predict the pressure drop in an inclined chute pressure drop. The predicted results from the model were found to be in reasonable agreement with the experimental results except for the pressure drop in the lower connection. The lower connection pressure drop was found to be affected by the riser velocity and L-valve aeration velocity. A correlation was developed to account for these effects, and was incorporated into the model, which improved the accuracy of the predicted results.