Measurement and modeling of particle-liquid heat transfer in liquid-solid and gas-liquid-solid fluidized beds

Many of the reactions performed in fluidized-bed reactors are exothermic an d catalytic. Overheating of the solid catalyst particles must be prevented through effective particle-liquid heat transfer. A rapid and accurate measu rement technique for particle-liquid heat transfer was developed. A model w hich describes the basic physical mechanisms yielded an expression without new empirical coefficients for robust, approximate predictions of the parti cle-liquid heat transfer coefficient in liquid-solid and gas-liquid-solid f luidized beds. This model takes into account three main effects of neighbor ing particles on particle heat transfer: the increase in approach liquid ve locity, the particle-particle contacts and the impairment of conduction and natural convection. (C) 1999 Elsevier Science Ltd. All rights reserved.