화학공학소재연구정보센터
AIChE Journal, Vol.61, No.1, 68-83, 2015
Systematic Study on Heat Transfer and Surface Hydrodynamics of a Vertical Heat Tube in a Fluidized Bed of FCC Particles
Bed-to-wall heat transfer properties of a vertical heat tube in a fluidized bed of fine fluid catalytic cracking (FCC) particles are measured systematically using a specially designed heat tube. Two important surface hydrodynamic parameters, i.e. the packet fraction ((pa)) and mean packet residence time ((pa)) based on the packet renewal theory, are determined by an optical fiber probe and a data processing method. The experimental results successfully reveal the axial and radial profiles of heat-transfer coefficient, the effects of superficial gas velocity, and static bed height on heat-transfer coefficient, most of which can be explained successfully by the measured (pa), an indicator of packet renewal frequency. (pa) is found to play a more dominant role than (pa) on bed-to-wall heat transfer. With a fitted correction factor, the modified Mickley and Fairbanks model is able to predict the heat-transfer coefficients with enough accuracy based on the determined packet parameters. (c) 2014 American Institute of Chemical Engineers AIChE J, 61: 68-83, 2015