Bubble column photobioreactor for Chlorella pyrenoidosa cultivation and validating gas hold up and volumetric mass transfer coefficient

The cultivation of microalgae in bubble column photobioreactors is essential to improve the biomass productivity for biofuel production. This work comprises the design and fabrication of bubble column photobioreactor of 20 L culture volume for the cultivation of Chlorella pyrenoidosa. The theoretically parameters such as gas hold up and volumetric mass transfer coefficient was predicted. The bubble column photobioreactor of 20 L culture volume was fabricated. The C. pyrenoidosa was cultivated in bubble column photobioreactor and the actual gas hold up and volumetric mass transfer coefficient was measured and with predicted values. The results showed similar trend of variation of experimental theoretically predicted gas hold up and volumetric mass transfer coefficient at different gas velocities. The comparison of biomass concentration and lipid content of C. pyrenoidosa cultivated in bubble column photobioreactor showed 1.18 +/- 0.02 g/L and 19.04 +/- 0.03% dwt, respectively, at the end of the cultivation period as compared with conical flask and glass tank cultivation.

Automated summary

This study designed and fabricated a 20 L bubble column photobioreactor for the cultivation of Chlorella pyrenoidosa. The results showed that the experimental and theoretically predicted gas hold up and volumetric mass transfer coefficient had similar trends at different gas velocities. Comparatively, the biomass concentration and lipid content of C. pyrenoidosa cultivated in the bubble column photobioreactor were higher than those in conical flask and glass tank cultivation.