HEAT-TRANSFER FROM VERTICAL INSERTS IN GAS-FLUIDIZED BEDS

For a chemical reaction of large exothermic or endothermicity when car ried out-in fluidized beds, an internal heat transfer surface addition al to the walls of the bed is often necessary. The heat transfer chara cteristics of vertical tubular inserts placed in the fluidized bed wer e examined by measuring the heat transfer from coils integral in the i nserts to the fluidized bed. It was found that the heat transfer coeff icients measured at the coils corresponded closely to the heat transfe r coefficient for bulk heat transfer measured in open fluidized beds u nder non-slugging conditions. Variations in heat transfer over the arr ay of inserts were small, and distributor effects were significant onl y at the onset of fluidization. The experimental results were successf ully related to an earlier correlation given for heat transfer in open beds. Copyright (C) 1996 Elsevier Science Ltd.