Solid–Liquid Mass Transfer in the Annular Region of a Taylor–Couette Flow Contacting Device

Dissolution of urea particles as a typical model system of solid-liquid mass transfer process was carried out in a Taylor-Couette flow contacting device in the absence of axial flow (i.e, batch mode), which is characterized by a rotating inner cylinder in a stationary one. The effect of pertinent parameters such as Taylor number (Ta), solid to solvent mass ratio, and operating temperature on the time-to-complete-dissolution of solid particles and time-averaged overall volumetric mass-transfer coefficients were investigated. It was found that the rotation speed of the rotating inner cylinder significantly affect the mass-transfer coefficient. Moreover, the time-to-complete-dissolution of the particles was modeled using the mean laminar velocity of the solvent within the annular gap of the contacting device over the speed range of 800 to 1400 rpm. Furthermore, the Sherwood number of particles was correlated in terms of the dimensionless Ta number and Schmidt number (Sc) with the experimental data.

Keywords:

Mass transfer coefficient , Dissolution , Taylor-Couette flow , Solid–liquid systems , Time-tocomplete- dissolution