Influence of solid particles on gas holdup and oxygen transfer in multiphase internal loop airlift reactor

Determination of gas holdup and oxygen transfer coefficient was conducted in an internal loop airlift reactor containing calcium alginate dispersed in a water-in diesel microemulsion media. The effect of riser superficial gas velocities in the range of 0.01 to 0.05m/s, solid loading (up to 15% v/v) and the size of solid particles (2-3mm and 3-4mm) on the gas holdup and volumetric oxygen transfer coefficient were studied in this work. All partial gas holdups and kLa increased, in the whole range of applied air superficial gas velocities. Gas holdup and kLa decreased with solid loading for calcium alginate with diameter 2-3mm can be due to bubble coalescence however for the 3-4mm calcium alginate beads a slightly increase in gas holdup and kLa was observed in low solid loading that related to bubble breakage.

Influence of solid particles on gas holdup and oxygen transfer in multiphase internal loop airlift reactor Keywords:

airlift bioreactor , three phase , gas holdup , oxygen transfer coefficient , microemulsion