Mixing Time in a Short Bubble Column

Mixing time measurements have been carried out in a 0.2m I.D. short bubble column (Hc/D <= 5) with different spargers and for different clear liquid height to diameter (HC/D) ratios. Superficial gas velocity has been varied in the range of 0.01m/s to 0.1m/s. Effect of bulk fluid viscosity on the mixing time has also been studied. The circulation cell model, with two fitted parameters viz. number of circulation cells, S and the inter-cell exchange velocity, Ve, has been used to predict and explain the variation in mixing time and the flow pattern in the short bubble column for different types of spargers.