Abstract
This paper presents the experiments on mixing efficiency for aerated media for a laboratory stirred bioreactor with a double turbine impeller. The effects of stirrer rotation speed, air volumetric flow rate and stirrer position on the shaft on mixing time for aerated water and simulated broths (CMCNa solutions) were analyzed. Compared to non-aerated broths, the results indicated that the variation of mixing time with the considered parameters is very different, due to the complex flow mechanism of the gas-liquid dispersion, a mechanism which is changed by changing the broth properties or fermentation conditions. Using the Statistics Toolbox of MATLAB some correlations between the mixing time and rotation speed, air volumetric flow rate and stirrer position on the shaft were established. The proposed equations agree well with the experiments, the average deviation being ?9.02%.
Highlights
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Summary
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