HEAT-TRANSFER TO LIQUID FLUIDIZED-BEDS IN ANNULI

Heat transfer coefficients to a liquid/solid fluidized bed in an annulus have been measured. Water and Bayer liquor have been used as liquids, while glass spheres and two types of steel cylinders have been used as solid particles. The possible operating parameters, heat flux, flow velocity and bulk temperature, have been varied over a wide range. The measurements with water are compared with the predictions of 13 correlations from the literature. The formation of sodium aluminium silicate on the heat transfer surface was studied for the fluidized bed section and for plain annular flow.