Author/Authors :
Karimi، Ali نويسنده Faculty of Electrical and Computer Engineering, Shahid Beheshti University, Tehran, Iran , , Golbabaei، Farideh نويسنده , , Mehrnia، Momammad Reza نويسنده Biotechnology Group, School of Chemical Engineering, University College of Engineering, University of Tehran, Tehran, Iran , , Neghab، Masoud نويسنده Department of Occupational Health, School of Health and Nutrition, Shiraz University of Medical Sciences, Shiraz, Iran , , Mohammad، Kazem نويسنده , , Nikpey، Ahmad نويسنده School of Health, Qazvin University of Medical Sciences, Qazvin , , Pourmand، Mohammad Reza نويسنده Department of Medical Biotechnology, School of Advanced Technology, Tehran University of Medical sciences, Tehran, IR Iran ,
Abstract :
In this study, a miniature stirred tank bioreactor was designed for treatment of waste gas containing benzene,
toluene and xylene. Oxygen mass transfer characteristics for various twin and single-impeller systems were
investigated for 6 configurations in a vessel with 10 cm of inner diameter and working volume of 1.77L. Three
types of impellers, namely, Rushton turbine, Pitched 4blades and Pitched 2blades impellers with downward
pumping have been used. Deionized water was used as a liquid phase. With respect to other independent
variables such as agitation speed, aeration rate, type of sparger, number of impellers, the relative performance of
these impellers was assessed by comparing the values of (KLa) as a key parameter. Based on the experimental data,
empirical correlations as a function of the operational conditions have been proposed, to study the oxygen transfer
rates from air bubbles generated in the bioreactor. It was shown that twin Rushton turbine configuration
demonstrates superior performance (23% to 77% enhancement in KLa) compared with other impeller compositions
and that sparger type has negligible effect on oxygen mass transfer rate. Agitation speeds of 400 to 800 rpm were
the most efficient speeds for oxygen mass transfer in the stirred bioreactor
