The effect of gas permeation through horizontally immersed membrane tubes on the heat transfer characteristics in a membrane assisted fluidised bed was investigated experimentally. Local time-averaged heat transfer coefficients from copper tubes arranged in a staggered formation with the membrane tubes to the fluidised bed were measured in a square bed (0.15 m x 0.15 m x 0.95 m) containing glass particles (75-110 ¿m) fluidised with air distributed via a porous plate, where the ratio of gas fed or removed through the membrane bundles and the porous plate distributor was varied. The experimental results revealed that high gas permeation rates through the membranes strongly decreased the heat transfer coefficient at high superficial gas velocities for tubes at the top of the tube bundle, which was attributed to the reduced mobility and heat capacity (higher dilution) of the emulsion phase. However, the effect of gas permeation was much less pronounced for tubes lower in the tube bundle because of the lower local dilution of the emulsion phase.
|Title of host publication||Proceedings of Fluidization XI|
|Place of Publication||Naples|
|Publication status||Published - 9 May 2004|