CFD simulating of hydrodynamic and mass transfer in airlift reactors and effect of bubble size

In this research method of CFD is used to simulate hydrodynamic and mass transfer in airlift reactors. The main purpose is to investigate effect of changing in bubble size on hydrodynamic and mass transfer characteristics. The most important parameter to simulate mass transfer is mass transfer coefficient(Kla).we have used two different equations (Kawase and Higbie) for simulation of the coefficient.the analysis shows that assuming a fixed size for bubbles and not using a good population balance based on experimental investigation makes a big difference in simulation results compared with experimental data .it was also found that Kawase model is more suitable than Higbie equation to simulate Kla for smaller bubbles that have not completely mobile surface whereas Higbie equation is suitable for bigger and fully mobile bubbles. The CFD simulation showed excellent agreement with reference experimental data.

کلیدواژه ها:

Airlift reactor (ALR) ، Hydrodynamic ، CFD ، Mass transfer coefficient ، Bubble size