Investigation of Operating Parameters’ Effects on Bubble Characteristics in a Co-Current Downflow Bubble Column

Bubble columns are frequently employed as multiphase reactors and gas-liquid contactors. In the bubble column, gas is dispersed into the liquid phase. The dispersion of gas into a liquid is the function of bubble size and its distribution. It also includes the complex process of coalescence and the break up of bubbles. The present research intends to examine the operating parameters' effect, including temperature on bubble characteristics in the ejector-induced downflow bubble column (i. d. ۰.۰۵ m X ۱.۶ m height) via Computational Fluid Dynamics (CFD) and experimental methods. Bubbles inside the column are analyzed and mean bubble diameters are obtained using a photographic technique. The effect of superficial gas velocity (۴.۲۵×۱۰−۳-۹.۶۸×۱۰−۳ m/s) and liquid velocity (۸.۵×۱۰−۲-۱۴.۱۱×۱۰−۲ m/s) on an average Sauter diameter is studied. The gas holdup variation with temperature (۶۰-۸۰ oC) is also examined. The temperature distribution at different axial locations (۰.۴۸-۱.۳۵ m) from the top of the column is observed using the CFD model. An empirical model for predicting the temperature, i.e., Tr (T/Tset), is proposed as a function of the Prandtl number, Weber number, Reynolds number, and Froude number.

کلیدواژه ها:

downflow bubble column ، Bubble size ، Interfacial area ، Temperature ، CFD