Abstract
In a batch gas liquid contactor, gas holdup in two phase (liquid gas) and three phase (gas liquid solid) fluidized bed has been measured experimentally; bubble size and the corresponding interfacial area of contact between the gas phase and liquid phase were calculated. Mass and heat transfer coefficients were evaluated at different solid contents and variable gas superficial velocities for the cooling and huhlidification of air bubbles into a water-sand slurry under fluidization conditions. Simplified models were derived to estimate the transfer coefficients.
Within the present range of parameters studied, the presence of solid particles decreased the gas holdup as well as the interfacial area of contact between gas and liquid, while both the heat and mass transfer coefficients increased several times compared to the two phase (liquid gas) values by a factor ranging from 2 to 5 depending on the solid contents and the gas superficial velocity. Applications of the present results in the design and operation of multiphase reactors were highlighted. (C) 2015 Elsevier Masson SAS. All rights reserved.